Monitoring book

Instrumentation for In-Situ Monitoring of Water Resources theories related to water storage and movement. Currently we are at the pinnacle of this revolution in hydrology where we are supported by real-time water quantity and quality monitoring systems at a ordable cost. For example, consider the evolution of theories on rainfall run-o generation mechanisms. It all started with visual observations and crude measurements of rainwater movement by Horton, who gave Hortonian overland ow theory (Horton, 1945). Using rain gauges, stream level markers and subsurface wells for experimental data collection on forested watershed areas, came the Variable Source Area concept - VSA (Hewlett and Hibbert, 1967). Using a large number of piezometric observation wells to collect the data on subsurface water movement in hilly areas, the Partial Area (Dunne and Black, 1970) concept of runo generation evolved. Using tensiometric and piezometric readings, precipitation data and soil analysis data on forested experimental watershed gave rise to an understanding that subsurface water movement played a dominant role in runo generation than the surface ow, which was considered non-intuitive up till this time (Harr, 1977). Using rain gauges, throughfall measurement using drums, ow measurement using V- notch weirs, Subsurface ow measurement using shallow pits, seepage measurement using tipping buckets in an experimental forested watershed, the theory of ow through macropores or preferential ow theory has evolved (Mosley, 1979), (Torres and Dietrich et al., 1998). Using V-notch weirs, potentiometric water level sensors, plastic trough collectors for throughfall measurement, piezometer nests installed perpendicular to stream, cup lysimeters, water samplers for the analysis of Cl-, Li+, and O18, the theories on contributions of event and pre-event water has evolved (Waddington, Roulet and Hill, 1993) By the onset of the 21st century, hydrologists are combining the experimental data with computational models to simulate and predict the watershed processes. As the complexity of these models increase, their data requirements also increase greatly. The most advanced models in the present day are data hungry and completely rely on large amounts of eld data for model calibration and validation. The increasing integration of eld and modelling investigations in hydrology is revolutionizing experimental design within which new technologies can be developed. The models can guide the instrumentation of catchments by helping to design optimal sampling strategies that are technically and economically feasible, while maximizing the probable information content of the collected data. Given the improved potential for high-resolution data collection in space and time, it is essential for this research frontier to continue (Soulsby et al., 2008). Thus, there is a need for cost-e ective instrumentation network that will provide fair access of water data to all its stakeholders and will promote transparency and better advocacy for water management while pushing the boundaries of hydrology as a science. The remainder of this chapter is structured as follows - First, the need of in situ measurements in critical water resources elements is described. Next, advances in modern monitoring systems are presented followed by a few example applications of in situ real-time instruments. Finally, a set of concluding remarks are presented. 81

Instrumentation for In-Situ Monitoring of Water Resources Figure 6.1 : Conceptual framework representing how continuous real-time monitoring of diverse water resources can lead to sustainable water management solutions Need of in Situ Instruments in Critical Water Resources Elements Rivers Rivers are dynamic systems that undergo signicant seasonal transformation in their shape and chemistry. The river channels expand, contract, fragment and then expand again in cycles every year, thus a ecting the quantity and quality of water it carries. These processes are further a ected by the anthropogenic interventions making the whole system a highly complex phenomenon. Despite so much awareness among the scientic community and nancial support from the governments, the rivers in India could not escape the devastating consequences of the rapid and unstructured nature of recent modernization. With rapid progress in industrialization, agriculture, communications and commerce, there has been a swift increase in the growth of number of small/large scale industries, agricultural areas and urban areas along the rivers. As a result, rivers are no longer merely a source of fresh water, but they have become conduits for receiving and transporting urban, agricultural and industrial wastes. Indian rivers are being polluted, endangering the lives of sh, amphibians along with millions of humans. The toxic waste being dumped from industries and agricultural practices is unregulated, and there is no systematic framework by which the e ect of each of these individual systems on the quality of water could be monitored and mitigated. It is now imperative to conduct holistic experimental investigation on river basins to 82

Instrumentation for In-Situ Monitoring of Water Resources understand the functioning of the river, both locally and regionally, with respect to continuous on-going changes, and identify the required measures for their healthy sustenance. To carry out a detailed study of these river systems, hydrologists have to continuously track the change in hydro-geo-environmental parameters across a river basin. That requires a large network of instrumentation on the river basin to monitor water quantity and quality in near real-time. Canals 2.5 Million Hectares of land in India is irrigated by canals with an average overall irrigation e ciency of 38% (Aquastat FAO, 2015). Irrigation engineers still majorly rely on colonial practices for operating and managing canals. Typically, irrigation water supply from reservoirs and canals are based on plans which are outdated, more or less xed on historical crop calendars estimated using 5 to 10 years old cropping pattern data, and di cult to amend because of lack of data on the current water requirement status of the water users. Most of the farmers are unaware of the supply plans and so could not use the supplied water e ectively. Currently there is a lack of transparency in water allocation and scheduling, and no framework exists to bridge the demand- supply gap. There is a need for real-time monitoring and estimations of water supply, water demand and the gap between them. With the advancements of sensor and communication technologies in the eld of Internet of Things, it is now possible to reliably track agro-hydro-geological parameters in real-time at an a ordable cost. The passive remote sensing data from satellites is mostly free and organisations around the world are intensively using the data on irrigation and agricultural applications. Lakes Surface storages such as ponds, lakes and reservoirs are the sources of drinking, irrigation and industrial water. The surface water storages are also responsible for maintaining ground water levels by allowing the recharge of rain water. As these water bodies are stagnant throughout few seasons, it is very important to maintain the quality of the water stored. As the water dries up during summer season, the solute concentrations naturally increase, this along with additional input from agricultural waste, sewage and industrial discharges pollute these water sources while also drastically a ecting geochemistry of the water source. Frequent monitoring of water quality and quantity in these water bodies can enable e ective management while protecting them from degradation. Farms Contribution of Gross Domestic Product (GDP) from agriculture in India is 16-17% with 50% of the country's workforce, and is continuously decreasing, implying that agriculture is no longer a protable occupation. Farmers rely on natural weather conditions and depend on groundwater, canal water or rainwater for irrigation, whose timing and quantum often do not match with crop demands. In addition, uncertainties arising due to changing climate scenario (weather patterns including rainfall, temperature; extreme weather events), 83

Instrumentation for In-Situ Monitoring of Water Resources increasing water stress and varying farm inputs (seeds, fertilizers and pesticides) are resulting in a signicant productivity loss to farmers, thus making conventional farming unsustainable. One of the great sustainability challenges of the coming decades is to increase food production while using less water, especially in countries with limited water resources and rising water demands. The optimal allocation of water to meet the crop demands is therefore vital. Irrigation water management is a complex task, which requires accurate knowledge of crop water demands, current water availability and expected precipitation to maximize water use e ciencies. A well-designed technology-based irrigation advisory service can accomplish this task. Drinking water supply Surface and subsurface water are the sources of drinking water supply across the country. The drinking water distribution networks involve the water movement through a series of closed conduits/pipes, underground sumps and elevated storage tanks before they reach nal water users. The e ciency of water transport from source to user is dependent on the right estimation of demand (quantum and timing), minimisation of conveyance losses and prevention of over and unauthorised extraction. With the increasing population and decreasing freshwater availability, it is critical to adopt techniques and methods that maximise the water supply and usage e ciencies. Most of the distribution networks in India are not monitored for supply, losses and extraction, the remaining are partially monitored using manual methods but are limited by punctuality and accountability of the operator collecting data. Thus there is a need and scope of instrumentation and automation, backed with computational data analysis for tracking the supply, losses and reach, and automating the water release thereby signicantly increasing the overall e ciency of the distribution network. This smart supply network can be linked with the implementation of policy level decisions on the water allocation and scheduling. Modern Monitoring Systems Environmental monitoring device We now describe the make and working of a modern monitoring device. This understanding and awareness of the terms should help the hydrologist make smarter decisions when selecting the instrument, optimally operate the instrument and interact with the generated data. With the progress in technology, modern monitoring device has become more power e cient, compact in size, of higher capabilities (accuracy, range) and even smarter. Figure 6.2 shows a conceptual diagram of one such device having the following ve blocks: 84

Instrumentation for In-Situ Monitoring of Water Resources Figure 6.2 : A Conceptual Diagram of the Instrument and the Cloud Ÿ The Device Core: comprises of the main microcontroller and essential electronic circuitry Ÿ Power Source: comprises of the batteries and energy harvesting devices (like solar panels) Ÿ Sensors: application-specic sensors Ÿ Transmission Module: using wireless transmission technologies like Cellular, Low Power WideArea Network (LPWAN) Ÿ Cloud Server: where we receive and store the data, and control the devices We will discuss the state-of-the-art enabling technologies for each block in the subsequent sections. But rst, let us highlight some crucial characteristics of these blocks and the device in general. These devices are installed in remote, harsh locations, so they have to be robust and power e cient. Such characteristics are realized by various features in its blocks. The device core is the brain of the instrument and it is more powerful than it used to be in a legacy instrument: it is capable of running complex algorithms and has better power management. The batteries used in these instruments are of high energy density (hence, compact) and have very low self-discharge, i.e. they retain their charge for extended durations (some for decades). Sensors communicate with the device core using standard protocols (like TTL-UART, RS232, I2C or analog). The device core takes readings from the sensors at regular interval (say, every 15 minutes) and stores them in its memory. When enough readings have been taken, it transmits the stored readings to the server using its transmission module. This is done sparingly (say, every 6 hours) to save power. The data are 85

Instrumentation for In-Situ Monitoring of Water Resources received on the cloud server, on which analytics and visualization can be done. Here, usually a web dashboard is provided. Using this, one can send messages to the device and control its functionality (like its logging rate and transmission rate). Advancements in communication technologies In wireless communication technologies, we are looking for outdoor and long-range technologies. Hence, short-range technologies (like ZigBee, Bluetooth) and medium range technologies (like WiFi, ZigBee-NAN) are not considered here. In long-range communication, the options that we have are Cellular Technologies (like 2G, 3G, 4G and 5G), LPWAN technologies (like Sigfox, LoRa, NB-IoT, LTE-M etc.) and Satellite Communication technologies (like VSAT). Cellular Technologies operate in licensed frequencies, are geared towards speed and are relatively high power consuming. LPWAN (Low Power Wide Area Network) is a new class of long-range wireless communication. These technologies support a larger number of devices per cell/tower and power requirement for devices is comparatively lower at the cost of very low data rate. Some of the components of these technologies lie in the open-source or unlicensed domain. E.g. Sigfox and LoRa operate in the unlicensed frequency bands and LoRa's networking stack is open source (except its physical layer). Satellite communication is usually expensive but it works in remote locations also. Advancements in embedded and electronics Over the past few decades, electronics and embedded hardware development has evolved in its capabilities, costs, accessibility and standardization. We can see an evolution from the 8051-based 8-bit microcontrollers to ARM-based 32-bit microcontrollers. We have devices today that are miniaturized form of computers, running full operating systems (like Raspberry Pi). The embedded devices have also become more accessible and can be programmed in high-level languages (like C++ and Python) and in a manner familiar to software programmers. This turn of events started in 2005 when the open-source Arduino platform was born. This development in the hardware industry was inspired by an already existing open-source revolution in the software industry. While earlier, an engineer would have to solder a microcontroller to a Printed Circuit Board along with necessary electronic components, Arduino provided a ready to use board with microcontroller and other components pre- soldered and an open-source software to program them. Apart from embedded developments discussed, signicant developments in Electronics have helped in miniaturizing the circuits and making them more power-e cient. We are briey summarizing those developments so that the reader can distinguish between what is legacy and what is modern. While earlier circuits operated on voltages like 24 V and 12 V, modern circuits are operating on lower voltages, 3.3V being the new logic standard and 5 V being the most common. Sensors now communicate with the circuit using digital protocols like TTL-UART, I2C and SPI, and protocols like RS232, RS485 and 4-20 mA have now 86

Instrumentation for In-Situ Monitoring of Water Resources become legacy (although still widespread). Analog sensors are now generally avoided as they are more prone to interference and their readings change with wire length. When using analog sensors, the analog-to-digital converter circuitry is packaged with the sensor itself so as to minimize interference issues. Advancements in Power Sources Legacy monitoring instruments used to be bulky primarily because of using heavy battery technology (like lead-acid). Battery technology has progressed a lot since then, and now we have batteries with much higher power density and also low self-discharge. Most of these batteries are Lithium-based. The key technologies now commonly used are Li-NMC (Lithium Nickel Manganese Cobalt Oxide), LiFePO4 (Lithium Iron Phosphate) and LiPo (Lithium Polymer) for rechargeable batteries, and LiSOCl2 (Lithium Thionyl Chloride) for non-rechargeable batteries. LiSOCl2 batteries have remarkably low self-discharge and are known to last for decades in fact. In energy harvesting, solar panels have become more e cient. However, logistical di culties (like stealing of panels) remain an issue in India, hence industries are now integrating panels into their design so that they are small and almost invisible. Advancements in cloud analytics Owing to the progress in computer hardware technologies (processor, RAM, Solid State Drive-SSD etc.), the servers have become cheaper and more powerful. While this has made handling of big data very e cient and complex computations possible, it has also enabled the usage of higher programming languages to be used for these purposes, which was not thought of before owing to the performance issues. The two clear winners here are Python and Javascript. While Python is gaining traction as the popular language for writing data analytics algorithms, Javascript is gaining traction for its back end and front-end development capabilities. Strong improvements have been made in web data exchange standards as well. For data exchange, the universal acceptance of JSON (JavaScript Object Notation) is a big development. JSON has replaced XML (eXtensibleMarkup Language) as the standard for web data exchange. With its universal acceptance as the web data exchange format, it is also being used for IoT data exchange as well. Example Applications Water Quantity Water quantity measurement is the basis for water budgeting and water distribution management. The surface and subsurface water resources available are usually quantied in terms of storage and discharge. Water level is used for estimating storage and ow measurement is used for estimating total discharge. With the recent advances in instrumentation, we can now continuously monitor water quantity in real-time. A brief comparison of di erent methods is given in Table 6.1. 87

Instrumentation for In-Situ Monitoring of Water Resources Table 6.1 : Comparison of sensor technologies for continuous monitoring of water quantity 1) Water level: Water level gauges with scale marked on them has been the standard for manual data collection. These scales are usually deployed on the riverbanks at a slope towards the center of the river. They are also deployed in canals, ponds, lakes and reservoirs for manual reading of the water level. Though the cost of instrumentation in this method is low, the cost of manpower to record the readings is considerable while the quality of data collected is limited by the bias, backgrounds and integrity of the gauge readers. Further, the process of data transfer from hand-written eld record books to digital format is very cumbersome and prone to errors, distortions and manipulations. Continuous automatic level recorders with data loggers have been around for many years. They use shaft encoders, bubblers and pressure transducers. These sensors are expensive, hard to maintain, have low operating life and require frequent calibrations. But with the advancement in communication and sensor technologies in the last decade, sensors with non-contact level measurement have evolved and can also be integrated with cellular network for real-time data transmission. The non-contact ultrasonic, laser and radar based sensors are reliable, long lasting and do not require frequent maintenance. Until recently, all these sensors were expensive and have high power requirements. So they had to be deployed with large lead-acid batteries and solar panels which attracted theft in eld deployments. As the embedded systems got to low-power consumption and sensors became economic, the automatic non-contact level gauges became very robust and a ordable for eld deployments. Among the non-contact sensors ultrasonic and radar are 88

Instrumentation for In-Situ Monitoring of Water Resources considered the most advanced and reliable for level measurements in diverse environmental conditions. a) Ultrasonic: The sensor sends ultrasonic pulses towards the water surface (Figure 6.3). These pulses get reected back from the water surface to the sensor. The sensor calculates the time between transmission and reception of the pulses. The time multiplied with speed of sound in air (at that temperature) will give the distance to the water surface. The range of ultrasonic sensors for reliable measurement is from 5 m to 10-12 m. Beyond this range, the error of the sensor signicantly increases, thus limiting the usage. The measurements from these sensors may have relative errors, which can be corrected by sensor calibration. The accuracy of the measurement is a proportion of the measured value, that is, the longer the distance, the lower the accuracy. These sensors consume very less power and are suitable for continuous operations for long durations. The sensor measurements are a ected by ambient temperature uctuations, humidity and fog. Figure 6.3 : Examples of ultrasonic water-level sensor deployed in rivers and lakes - (a) sensor with solar panels attached to it, and (b) sensor operating on a D size primary battery (Courtesy - Kritsnam Technologies). b) Radar: The principle of measurement is similar to ultrasonic sensor (Figure 6.4). Instead of sound waves, the sensor emits electromagnetic waves that get reected by the water surface. The radar sensors use this reected wave (Echo) to measure the distance of the water surface. The radar sensor has longer range than the ultrasonic sensor - typically from 5 m to 50 m range, but the upper limit can go upto 100 m. Unlike ultrasonic sensors, they o er absolute accuracy, i.e. the accuracy doesn't much vary with the target distance. The radar sensors have comparatively higher power requirements than the ultrasonic sensors. The sensor measurements are relatively una ected by the ambient environmental conditions. 89

Instrumentation for In-Situ Monitoring of Water Resources Figure 6.4 : Examples of radar water-level sensor deployed on Ganga River in Rudraprayag - (a) sensor operating on a D size primary battery, and (b) sensor with solar panels attached to it (Courtesy - Kritsnam Technologies). 2) Flow measurement: The concept of ow measurement has been recognized as very important, particularly as water conservancy, farming and irrigation became important to human civilizations. A ow meter is an instrument to measure mass or volumetric ow rate of a liquid or a gas. a) Pipe flow: Flow meters are frequently used in industries such as petrochemicals, pharmaceuticals, home energy, pulp and building and metallurgy. There are various types of owmeters which di er in their principle and area of application. Examples include Variable Area (rotameters), Rotating Vane (paddle & turbine), Positive Displacement, Di erential Pressure, Vortex Shedding, Thermal Dispersion, Magnetic, Thermal Mass, Coriolis Mass and Ultrasonic owmeters (Figure 6.5). Ultrasonic is one of the latest technologies emerging in the area of ow measurement. It has no pressure loss, and at the same time it is accurate and easy to maintain. There are two main types of ultrasonic ow meters: Doppler and transit time. Transit-time ow meters measure 90

Instrumentation for In-Situ Monitoring of Water Resources ow rate by using time di erence between upstream and downstream sound propagation intervals. This leads to very good accuracy (±1-2%).This method works well for clean liquid applications.Applications include pure water, sea water, wash water, process liquids, oils, chemicals, and any homogeneous liquids which are capable of ultrasonic wave propagation. Transit time ow meters are sensitive to suspended solids or air bubbles in the uid. The Doppler E ect Ultrasonic Flow meter use reected ultrasonic sound to measure the uid velocity. By measuring the frequency shift between the ultrasonic frequency source, the receiver, and the uid carrier, the relative motion are measured. The resulting frequency shift is named the Doppler E ect. They work well with suspension ows where particle concentration is above 100 ppm and particle size is larger than 100 µm, but less than 15% in concentration. These owmeters are easier to make, but they are less accurate (±5%) and economic than a transit time owmeter. (Spire Metering Technology, 2019). b) Open channel flow: Open channels are those natural and man-made structures through which water ows with a free surface. Examples of such structures include streams, rivers, irrigation ditches, canals, partially full pipes, and water conveyance umes. There are many methods of measuring discharge in open channels such as volumetric method using measuring containers, velocity area method using current meters and moving ADCP (Acoustic Doppler Current Proler), tracer dilution method using chemical and radioactive tracers, slope-area method, stage-discharge rating curves, velocity area method using xed ultrasonic/radar doppler and ultrasonic transit-time based sensors. Most of these methods are not suitable for continuous monitoring and carry several measurement errors. Transit- time and Doppler based continuous ow measurement are the future of real-time discharge monitoring in open channels. Instruments based on ultrasonic technology are relatively new but are very promising (www.openchannelow.com). Figure 6.5 : Examples of ultrasonic pipe ow meters (Courtesy - Kritsnam Technologies). 91

Instrumentation for In-Situ Monitoring of Water Resources Water quality The water quality testing is usually performed in laboratories but advances in modern techniques are capable of superseding conventional methodology of manual sampling, storing and testing of water samples in the lab while allowing the users to perform testing in the eld itself (Figure 6.6) for few specic parameters as described below. A brief comparison of di erent methods is given in Table 6.2 . 1) pH: Dened as the negative logarithm to the base 10 of concentration of hydrogen ions (- log10[H+]) in solution. For most of the domestic consumption and drinking purpose it is recommended that the pH of water stays between 6.5 and 8.5 pH can be measured using test strips, colorimeters and potentiometric meters. The most commonly used method by researchers is Potentiometric pH meters. It usually has a glass electrode and a reference electrode, or a combination electrode. Table 6.2 : Comparison of sensor technologies for continuous monitoring of water quality 2) Electric conductivity: EC of water is dened as its ability to conduct current. Dissolution of salts in water results in a free state of ions responsible for increasing its conductivity. Drinking water should have the conductivity between 50-500 µS/cm. The common measurement methods are 2 electrodes method, 4 electrode method and inductive method. The widely used sensors consist of two metal electrodes, usually stainless steel or titanium, in contact with the electrolyte solution. 92

Instrumentation for In-Situ Monitoring of Water Resources 3) Dissolved Oxygen: Various life forms like sh, plants, invertebrates respire through dissolved oxygen present in a water body. It is measured in parts per million (ppm)/ (mg/L) or percentage. Too low or too high dissolved oxygen levels is harmful for their health. According to Central Pollution Control Board (CPCB) criteria, DO should be 6 mg/L or more for drinking purpose, 5 mg/L for bathing purpose and at least 4 mg/L for sheries and aquatic life maintenance. The common measurement methods are Clark cell electrodes and luminescence based optodes. 4) Turbidity: Turbidity of a water is dened as its cloudiness or haziness. Turbidity in water is caused by suspended particles or colloidal matter that obstructs light transmission through the water. It may be caused by inorganic or organic matter or a combination of the two. Turbidity is measured in NTU using nephelometer, which measures the intensity of light scattered at 90 degrees as a beam of light passes through a water sample.The turbidity of drinking water should be less than 5 NTU (Bureau of Indian Standards, 2012). Figure 6.6 : Example of oating buoy based continuous water quality monitoring instrument (Courtesy - Kritsnam Technologies). Soil moisture Soil moisture (volumetric water content), dened as the volume measure of the water contained in a volume of soil, is a critical contributing variable for computing water and energy balances, and is directly utilized in estimations of water and heat transport, and irrigation management (Kargas and Konstantinos, 2012). Due to it being a key parameter in various elds including hydrology, climatology, environmental science, and ecohydrology (Bogena et al., 2017), the scientic community has seen the development of a variety of non-destructive, indirect methods of measurement of soil moisture (Bogena et al., 2017; Oschner et al., 2013; Robinson et al., 2008; Zhang et al., 2016). Some of the methods which have been used for point soil moisture measurements include neutron thermalization, time 93

Instrumentation for In-Situ Monitoring of Water Resources domain transmission (TDT), time domain reectometry (TDR), frequency domain reectometry (FDR), electrical capacitance and impedance and resistance-based methods. The electromagnetic techniques (such as TDR, TDT, capacitance sensors) are based on the phenomenon that soils are dielectric materials and that the properties of electromagnetic (EM) wave propagation in soils primarily depends on liquid water due to its su ciently larger dielectric permittivity (epsilon_r = 81) than that of other surrounding soil components (solid soil or gaseous air) (Bogena et al., 2017). The frequency of operation for Figure 6.7 : Example of soil moisture monitoring instrument deployed in kanpur farms (Courtesy - Kritsnam Technologies). TDR and TDR sensors is very high, while capacitance sensors operate at low frequencies, between 50 and 150 MHz (Bogena et al., 2017). Higher frequency sensing is more favourable as measurements tend to be lesser inuenced by the soil's electrical conductivity and imaginary component of the dielectric permittivity (Blonquist et al., 2005), and hence the TDR method is recognized to be a highly accurate EM based method (Robinson et al., 2003; Noborio et al., 1994). Conclusion Governmental, national, and international private organizations striving for improving water health and water accounting are limited by factual data to back their interventions and to improve upon them. The populations are not su ciently sensitized to their interactions with the water systems and are largely unaware of the best practices in water conservation. The available water resources in the country are limited but the demand for them has only been increasing. If we do not achieve high e ciencies in water usage, we will soon be facing nationwide water and food crisis. So, there is a need to empower our country with decision support systems that utilise real-time data and generate strategies for improving 94

Instrumentation for In-Situ Monitoring of Water Resources water use e ciencies.Investments in real-time in situ monitoring instruments will enable e cient water resources management and will further strengthen our knowledge of hydrology as a science. With the advancements in sensor, communication, and embedded technologies, we can now move towards a vision of data driven water resources management across the country. We need to formulate and adopt uniform standards for in situ measurements and database management across the country. We need to setup centers for validating, testing and calibrating these instruments. The data access should be transparent and accessible to all. References Blonquist JM, Jones SB, Robinson DA (2005). Standardizing Characterization of Electromagnetic Water Content Sensors: Part 2. Evaluation of Seven Sensing Systems. Vadose Zone Journal, 4(4), 1059–69.https://doi.org/10.2136/vzj2004.0141. BogenaHeye, Johan Huisman, Bernd Schilling, Ansgar Weuthen, Harry Vereecken. (2017). E ective Calibration of Low-Cost Soil Water Content Sensors. Sensors, 17 (12), 208.https://doi.org/10.3390/s17010208. Bureau of Indian Standards (2012). Drinking-Water Specication (Second Revision) IS 10500: 2012. http://cgwb.gov.in/Documents/WQ-standards.pdf. Cosh Michael H, Tyson E Ochsner, Lynn McKee, Jingnuo Dong, Je rey B Basara, Steven R Evett, Christine E Hatch, et al. (2016). The Soil Moisture Active Passive Marena, Oklahoma, In Situ Sensor Testbed (SMAP-MOISST): Testbed Design and Evaluation of In Situ Sensors. Vadose Zone Journal, 15(4), vzj2015.09.0122. https://doi.org/10.2136/vzj2015.09.0122. Dean TJ, BellJP, BatyAJB(1987). Soil Moisture Measurement by an Improved Capacitance Technique, Part I. Sensor Design and Performance. Journal of Hydrology, 93(1–2), 67–78https://doi.org/10.1016/0022-1694(87)90194-6. Dunne Thomas, BlackRichard D (1970). Partial Area Contributions to Storm Runo in a Small New England Watershed. Water Resources Research, 6 (5), 1296–1311 https://doi.org/10.1029/WR006i005p01296. FAO(2012).AQUASTAT Country Prole –India. FAO. http://www.fao.org/3/ca0394en/CA0394EN.pdf. Harr RD (1977). Water Flux in Soil and Subsoil on a Steep Forested Slope. Journal of Hydrology, 33(1–2), 37–58.https://doi.org/10.1016/0022-1694(77)90097-X. Hewlett John D, Alden R Hibbert (1967). Factors A ecting the Response of Small Watersheds to Precipitation in HumidAreas. Forest Hydrology, 1, 275–290. Horton RE (1945). Erosional Development of Streams and Their Drainage Basins: Hydrophysical Approach to Quantitative Morphology. Bulletin of the Geological Society of America, 56, 275-370. Progress in Physical Geography: Earth and Environment 19 (4), 533–54.https://doi.org/10.1177/030913339501900406 95

Instrumentation for In-Situ Monitoring of Water Resources Kargas George and Konstantinos X Soulis (2012). Performance Analysis and Calibration of a New Low-Cost Capacitance Soil Moisture Sensor. Journal of Irrigation and Drainage Engineering, 138(7), 632–41.https://doi.org/10.1061/(ASCE)IR.1943-4774.0000449. Mosley M Paul (1979). Streamow Generation in a Forested Watershed, New Zealand. Water Resources Research, 15(4), 795–806.https://doi.org/10.1029/WR015i004p00795. Noborio K, McInnesKJ, HeilmanJL (1994). Field Measurements of Soil Electrical Conductivity and Water Content by Time-Domain Reectometry. Computers and Electronics in Agriculture, 11(2–3), 131–42.https://doi.org/10.1016/0168- 1699(94)90003-5. Ochsner Tyson E, Michael H Cosh, Richard H Cuenca, Wouter A Dorigo, Clara S Draper, Yutaka Hagimoto, Yann H Kerr, et al. (2013). State of the Art in Large-Scale Soil Moisture Monitoring. Soil Science Society ofAmerica Journal, 77 (6), 1888–1919. https://doi.org/10.2136/sssaj2013.03.0093. Open Channel Flow (2019). Methods of Measuring the Flow of Water in Open Channels. Blog. 2019.https://www.openchannelow.com/blog/methods-of-measuring-ows-in- open-channels. Qu W, Bogena H R, Huisman J A, Martinez G, Y A Pachepsky, and H Vereecken(2014). E ects of Soil Hydraulic Properties on the Spatial Variability of Soil Water Content: Evidence from Sensor Network Data and Inverse Modeling. Vadose Zone Journal,13(12) vzj2014.07.0099.https://doi.org/10.2136/vzj2014.07.0099. Robinson DA, CampbellCS, HopmansJW, HornbuckleBK, JonesSB, KnightR, OgdenF, Selker J, and Wendroth O (2008). Soil Moisture Measurement for Ecological and Hydrological Watershed-Scale Observatories: A Review. Vadose Zone Journal, 7 (1), 358–89.https://doi.org/10.2136/vzj2007.0143. Robinson DA, Jones SB,Wraith JM,Or D and FriedmanSP(2003).AReview ofAdvances in Dielectric and Electrical Conductivity Measurement in Soils Using Time Domain Reectometry. Vadose Zone Journal, 2(4), 444.https://doi.org/10.2136/vzj2003.0444. Rosenbaum U, Huisman JA,Vrba J, VereeckenH, and BogenaHR(2011). Correction of Temperature and Electrical Conductivity E ects on Dielectric Permittivity Measurements with ECH 2 O Sensors. Vadose Zone Journal, 10(2), 582–93. https://doi.org/10.2136/vzj2010.0083. Seyfried Mark S, and MurdockMark D (2004). Measurement of Soil Water Content with a 50-MHz Soil Dielectric Sensor. Soil Science Society of America Journal, 68 (2), 394–403.https://doi.org/10.2136/sssaj2004.3940. Soulsby C, Neal C, LaudonH, BurnsDA, MerotP, BonellM, DunnSM, and Tetzla D. (2008). Catchment Data for Process Conceptualization: Simply Not Enough? Hydrological Processes, 22(12), 2057–61.https://doi.org/10.1002/hyp.7068. Spire Metering Technology (2013). Ultrasonic Flowmeters: Selecting the Right Flowmeter 96

Instrumentation for In-Situ Monitoring of Water Resources for Your Liquid Application https://www.owcontrolnetwork.com /instrumentation/ow- measurement/ ultrasonic/article/15559209/ultrasonic-owmeters-selecting-the-right- owmeter-for-your-liquid-application. Swaminathan, MankombuSambasivan, and Vaidyanathan BhavaniR(2013). Food Production & Availability-Essential Prerequisites for Sustainable Food Security. The Indian Journal of Medical Research, 138(3), 383. Torres Raymond, DietrichWilliam E, MontgomeryDavid R, AndersonSuzanne P, and LoagueKeith (1998). Unsaturated Zone Processes and the Hydrologic Response of a Steep, Unchanneled Catchment. Water Resources Research, 34(8), 1865–79. https://doi.org/10.1029/98WR01140. Waddington, JM, RouletNT, and HillAR(1993). Runo Mechanisms in a Forested Groundwater Discharge Wetland. Journal of Hydrology, 147(1–4), 37–60. https://doi.org/10.1016/0022-1694(93)90074-J. Zhang Dianjun, and ZhouGuoqing(2016). Estimation of Soil Moisture from Optical and Thermal Remote Sensing:AReview. Sensors, 16(8), 1308. https://doi.org/10.3390/s16081308. 97

7 WATER QUALITY ASSESSMENT Vasudha Agnihotri Abstract The chapter is developed with the aim of providing the basics of sampling strategies important for water quality assessment and a brief about some of the water quality parameters important with reference to the Central Pollution Control Board (CPCB) guidelines. The sampling strategies included di erent types of water sampling, their timing, frequency, storage, and other precautionary measures important for sampling. The details of some important water quality parameters have also been included in the chapter. The chapter will be useful for the student and researchers working in the eld of environment science, hydrology, chemistry, and many other related areas. Keywords: Water quality, sampling, storage of water sample, water quality standards, pollution Background Water is an important environmental parameter which needs to be assessed due to its usages in our day-to-day life. The usages are ranging from drinking purposes, household activities, agriculture (irrigation), hydroelectric power plants, transportation, infrastructure, tourism, recreation, and many other areas. All these activities directly or indirectly a ect the quality of water. Along with anthropogenic activities, natural hydrogeochemical processes also inuence the water quality. The water quality can change through leaching of harmful chemical and other contaminants at any point of use during its ow on the surface as well as in case of ground water resources, therefore the continuous monitoring and assessment of water is essential. The proper management of fresh water available on the earth involves a well-designed monitoring and assessment strategies so that it could be available to all the human beings for their various activities (Figure 7.1). Vasudha Agnihotri, Ph.D. Centre for Land and Water Resource Management G.B.Pant National Institute of Himalayan Environment, Kosi - Katarmal, Almora [email protected] Monitoring and A ssessment of Environmental Parameters Eds. V. A gnihotri, S. Rai, A . Tiwari, S. Mukherjee, K. Kumar, R. Joshi, GBPNIHE, A lmora, Uttarakhand, India ©GBPNIHE 2020 98

Water Quality A ssessment Water management Information needs Information utilization Monitoring strategy Reporting Network design Data analysis Sample collection Data handing Laboratory analysis Figure 7.1 : Monitoring cycle (Timmerman et al., 1997) Water quality monitoring is the programmed process of sampling, measurement and recording of various water characteristics, generally carried out with clear aims and objectives. Before staring the assessment works, some important points need to be assessed about the selected area such as details of the area, its environmental conditions and processes, including demographic details, such as population, land use, hydraulic structures, (ground) water extraction sites and recreational areas, meteorological and hydrological information, including hydrographs of river ows, and precipitation/ evaporation data at stations as close as possible to the water course, summary of actual and potential water uses etc (WHO, 2013). The actual monitoring strategies may vary according to the type of targeted water resources such as river, lake, springs etc. After getting all the relevant information, water sampling and further analysis can be done based on the requirement. All freshwater bodies are inter-connected, from the atmosphere to the sea, via the hydrological cycle from rainwater to marine saltwater. Major water bodies are river, lake and groundwater along with other transitional water bodies such as reservoirs, ood plain, and marshes etc. Residence time and ow velocity of water in these water bodies varies (Figure 7.2). Rivers are characterised by uni-directional current with a relatively high, average ow velocity ranging from 0.1 to 1 m s-1, lakes are characterised by a low, average current velocity of 0.001 to 0.01 m s-1 (surface values), while groundwaters are characterised by a rather steady ow pattern ranging from 10-10 to 10-3 m s-1 and are largely governed by the porosity and permeability of the geological material. These characteristics a ect the water quality. 99

Water Quality A ssessment Running Streams Rivers waters Shallow Deep Standing lakes lakes waters Reservoirs Ground- waters Karst Alluvial Sedimentary Deep aquifers aquifers aquifers Bank ltration Hours Days Months Years 10 years 100 years 1,000 years Figure 7.2 : Water residence time in inland freshwater bodies (Meybeck and Helmer, 1989) Assessment of water quality includes the evaluation of their physico-chemical and biological properties. The other important parameters during assessment of water quality are their sampling and storage. This chapter will cover the brief details of sampling and storage of water and its quality attributes, with respect to the guidelines of Central Pollution Control Board (CPCB), Government of India. Sampling and Storage Objective of sampling is to collect a portion of material small enough in volume/weight to be transported comfortably and yet large enough for analytical purposes while still representing the material being sampled.Samples should be representative of the system, so that well mixed zone can be selected.Areas of turbulence and at weirs should be avoided. In cases of owing surface water, the reference station should be upstream of any discharge point which allows us to ascertain the background water quality. Additional downstream stations can be xed to assess the extent of inuence of discharge and to nd the recovery point. Broadly, water sampling can be done in the following ways: 1. Grab sampling: Single samples collected at a specic spot at a site in specied time, when the source is known to be constant in composition for an extended period (Figure 7.3 (a)). 2. Composite sampling: Representative sampling for heterogeneous matrix (which varies from time to time or depth or at many sampling locations) and by combining 100

Water Quality A ssessment portions of multiple grab samples collected at regular intervals. This method can be used only for parameters that will remain unchanged under di erent sampling conditions, preservation and storage. 3. Integrated sampling:Sampling is carried out by taking the mixture of grab samples collected from di erent points simultaneously. The points may be with horizontal or vertical variation. 4. In-situ measurements: Some determinations are more likely to be a ected by sampling and sample storage than others.If possible, these parameters should be analysed on the sampling site or, even better, in-situ. Such parameters are pH, electrical conductivity, dissolved oxygen, temperature etc (Figure 7.3 (b)). (a) (b) Figure 7.3 : Water Sampling (a) grab; (b) In-situ measurements 101

Water Quality A ssessment Sampling frequency is also important for better representation and accuracy. The selection of number of samples requires per point also depends upon the target for which the data is required. In trend analysis, one sample per month is enough, while for early warning monitoring hourly or daily observation might be required (Table 7.1). Table 7.1 : Sampling frequency for di erent types of water bodies Water body Sampling frequency Baseline stations Streams Minimum : 4 per year, including high-and low-water stages Headwater lakes Optimum : 24 per year (every second week); weekly for total Trend stations suspended solids Rivers Minimum : 1 per year at turnover; sampling at lake outlet Lakes/reservoirs Optimum : 1 per year at turnover, plus 1 vertical prole at end of Groundwaters stratication season Minimum : 12 per year for large drainage areas, approximately 100,000 km2 Maximum : 24 per year for small drainage areas, approximately 10,000 km2 For issues other than eutrophication: Minimum : 1 per year at turnover Maximum : 2 per year at turnover, 1 at maximum thermal stratication For eutrophication: 12 per year, including twice monthly during the summer Minimum : 1 per year for large, stable aquifers Maximum : 4 per year for small, alluvial aquifers Karst aquifers: same as rivers Source: UNESCO-IHE Institute for Water Education, OLC Water Quality A ssessment, Course 3 Sampling Container and Preservation of Water The water samples should be collected in clean, pre-rinsed glass or polythene bottles, and then can be stored. Selection of right type of sampling container and preservation of samples immediately after sampling is important. Water naturally contains di erent types of organic and inorganic compounds which can react with the surface of the sampling bottle. So, containers should be selected based upon the target analytes (target ions and other compounds) (Table 7.2). Without proper preservation, sample composition might change due to di erent possibilities such as: 102

Water Quality A ssessment · Consumption of certain constituents Box 7.1 by microbes Precautions while sampling · Oxidation of some of the compounds Ÿ Water sampler should be lled with by the dissolved oxygen present in the sample water or not is based on type of · Precipitation of salts e.g. calcium analysis. carbonate, aluminium oxide from the Ÿ If the samples are collected for the liquid determination of organic compounds · Loss of sample in the vapour phase like pesticides, PAH, VOC etc. and · Absorption of carbon di oxide from for sulphide ions, container should the air due to which pH of the sample be lled without any air space. might change · Absorption of metal ions and certain Ÿ For microbiological and inorganic organic compounds onto the container's analysis, space should be left for surface aeration and mixing in the sampling · Depolymerization of polymerized bottle (at least 1% of the container products and vice versa volume). Precautions should also be taken during sample lling (Box 7.1). Cleaning Procedures The cleaning of samplers, sampling bottles and other labware is essential, that are used for collection and analysis of target sample (ISO, 2018). Depending on the parameter, di erent cleaning procedures can be applied. For example, if the target ions are heavy metals then the sample bottles should be cleaned with 1:1 diluted Nitric acid (supra pure quality) along with at least three times washing with double distilled water. For the sampling of water containing trace organic (chlorinated) compounds, like pesticides, the sampling bottles should be cleaned with the solvent used for extraction (of high purity). So, the person going for sampling should have these reagents with them during eld visit (Table 7.2). Table 7.2 : Recommended preservative treatment and maximum permissible storage time for water quality variables (ISO 5667-3:2018) Determinant Material of sample container Method of Maximum storage time Ca, Mg, Na, K (Plastic(P)/ Borosilicate preservation Anions (Br, F, Cl, 1 month NO3, PO4, SO4) glass (BG)/ glass) (G) Up to 1 month, lter on site P, acid washed HNO3, pH 1-2 P/ G 1-5°C or freeze -20°C 103

Water Quality A ssessment Alkalinity, HCO3 P/ G Cool to 1-5°C 24 hours BOD P/ G 1-5°C or freeze -20°C 24 hours or 1 month respectively COD P/ G H2SO4, pH 1-2 1 month Nitrogen, ammonia P/ G H2SO4, pH 1-2 and 21 days, lter on site Cool to 1-5°C Nitrogen, nitrate P/ G H2SO4, pH 1-2 and cool to 1 day to 1 month 1-5°C or freeze -20°C Nitrogen, nitrate P/ G H2SO4, pH 1-2 and Cool to 1 day to 1 month N, Kjeldahl and TN P 1-5°C or freeze -20°C H2SO4, pH 1-2 and Cool to 6 months in dark 1-5°C or freeze -20°C TN: 1 month Phosphorus, total P/G/BG acid washed H2SO4, pH 1-2 and Cool to 6 months 1-5°C or freeze -20°C Phosphorus, P/G/BG acid washed Cool to 1-5°C or freeze 1 month, lter on-site dissolved P/G (brown) to -20°C Chlorophyll-a 1-5°C or freeze to -20°C 1 day, 1 month respectively Heavy metals, P/BG acid washed HNO3, pH 1-2 6 months except Hg BG acid washed HNO3, pH 1-2, add K2Cr2O7 1 month Mercury (0.05%) Mineral oil G pH 1-2 with HCl or H2SO4 1 month G Organic-chlorine 1-5°C 1 day-1 week pesticides The sample bottles should always be clearly labelled with all relevant information and should also be noted in a special worksheet or notebook (Box 7.2). Water Quality Water quality is dened as those physical, chemical, or biological characteristics of water by which the user evaluates its acceptability (MINARS/27/2007–08). For example, the drinking water should be pure and potable. Similarly, for irrigation dissolved solids and toxicants are important, for outdoor bathing pathogens are important and water quality is controlled accordingly. Textiles, paper, brewing, and dozens of other industries using water, have their specic water quality needs (Table 7.3). 104

Water Quality A ssessment Now days, the water of even the healthiest Box 7.2 rivers and lakes is not pure. All water contains many naturally occurring (Bartram et al., 1996) substances (mainly bicarbonates, sulphates, Minimum information required for the sodium, chlorides, calcium, magnesium, and label potassium) along with the chemical Ÿ Date and time of sampling contaminants released through various Ÿ Sample eld code anthropogenic activities. The sources of Ÿ Sampling point naturally occurring substances are soil, Ÿ Nature of sample: E uent / Surface geologic formations, and terrain in the catchment area (river basin); surrounding water / Ground water / Others vegetation and wildlife; precipitation and Ÿ Type of sample (Grab/ Composite/ runo from adjacent land; biological, physical and chemical processes in the water Integrated) etc. Water quality can be broadly classied Ÿ Pre-treatment or preservation carried into three types: out on the sample Ÿ Any special notes for the analyst Ÿ Name and sign of sample collector Ÿ Physical properties: turbidity, colour, taste, odour and temperature measurements Ÿ Chemical properties: organic and inorganic dissolved and particulate constituents, pH, salinity and hardness of water Ÿ Biological properties: The abundance and distribution of aquatic life (microscopic viruses, bacteria, and protozoans; as well as phytoplankton, zooplankton, insects, worms, large plants and sh) The information of water quality is generally useful as per specic quality needs. In India, the Central Pollution Control Board (CPCB) has developed a concept through which ve designated best uses of water have been identied (Table 7.3). This classication helps the water quality managers and planners to set water quality targets and to design suitable restoration programs for various water bodies. Table 7.3 : Classication of surface water based on usage Characteristics Designated best use DO (mg/L) Drinking water Outdoor Drinking water Propagation of Irrigation, BOD (mg/L) industrial source without bathing source with wildlife and cooling and controlled conventional (organized) conventional sheries disposal treatment but with treatment chlorination ABC DE 654 4- 233 -- 105

Water Quality A ssessment pH 6.5-8.5 6.5-8.5 6.0-9.0 6.5-8.5 6.5-8.5 TDS (mg/L) 500 - 1500 - 2100 Hardness 200 - - EC (µS/cm) - - - - - Ammonia-N (mg/L) - - - 1.2 2250 Nitrate-N (mg/L) 20 - - - Fluoride (mg/L) 1.5 1.5 50 - - Sulphate (mg/L) 400 - 1.5 - - Chloride (mg/L) 250 - 400 - - Sodium absorption ratio - - 600 - 1000 - 600 1.2 Source: Guidelines for water quality monitoring, CPCB (MINA RS/27/2007–08) In India, for drinking water, specications specied by Bureau of Indian Standards (BIS) (IS 10500:2012) has been followed which contains the acceptable and prescribed limit of water quality. If any parameter exceeds the limit, then the water is considered unt for human consumption (Table 7.4). Table 7.4: Drinking water quality parameters and their standard limits (IS: 10500 - 2012) S. NO. Parameters Units Quality requirements 1 Colour Hazen units Desirable Maximum 2 Odour - 5 15 3 Taste - 4 Turbidity NTU Agreeable Agreeable 5 pH value - Agreeable Agreeable 6 Total hardness (as CaCO3) mg/l 7 Iron mg/l 1 5 8 Alkalinity mg/l 6.5 to 8.5 No relaxation 9 Aluminium mg/l 10 Anionic detergents mg/l 200 600 0.3 No relaxation 106 200 0.03 600 0.2 0.2 1

Water Quality A ssessment 11 Arsenic mg/l 0.05 No relaxation 0.5 1 12 Boron mg/l 0.01 75 No relaxation 13 Cadmium mg/l 250 200 0.05 1000 14 Calcium mg/l 0.05 0.01 No relaxation 15 Chlorides mg/l 500 1.5 1 0.05 16 Chromium mg/l 0.05 2000 0.1 1.5 17 Copper mg/l 0.001 0.05 No relaxation 18 Cyanide mg/l 45 0.3 Absent 19 Dissolved Solids mg/l 0.001 No relaxation 0.001 No relaxation 20 Fluoride mg/l 0.1 No relaxation 1 21 Lead mg/l 0.2 0.001 0.01 0.002 22 Manganese mg/l 200 No relaxation 5 No relaxation 23 Mercury mg/l No relaxation 24 Mineral oil mg/l 1 No relaxation 25 Nitrate mg/l 400 26 Pesticides mg/l 15 27 Phenolic compounds mg/l 28 Polynuclear aromatic Hydrocarbons mg/l 29 Radioactive materials (α-emitters) Bq/l 30 Radioactive materials (β-emitters) Pci/l Residual, free Chlorine mg/l 31 Selenium mg/l 32 Sulphate mg/l 33 Zinc mg/l Selection of water quality variable should be based on the requirement e.g. the quality assessment of water used for agricultural purpose needs di erent variable than that used for drinking purposes. So, the assessment is generally based of the program for which the study is being carried out. The water, having 107

Water Quality A ssessment high sodium (Na+) content, is not suitable for irrigation as it a ects the soil structure by decreasing its permeability. This property is determined in terms of sodium adsorption ratio (SAR), which is calculated for water is used for irrigation purpose (Box 7.3; Table 7.3). Common ions, biodegradable organics and Coliform bacteria are the dominating parameters of water quality, which vary seasonally. The Central Pollution Control Board (CPCB), therefore, enlists them as core or general parameters in its monitoring programmes along with other monitoring related water quality data sets, under the National Water Quality Monitoring Program (Figure 7.4). Some of these parameters have been described in the coming paragraphs, which will provide an overview of those parameter in terms of their relevance and standard methods used for their measurement. Core parameters pH pH is the measurement of acidity or alkalinity of water with reference to the ionization of pure water. It is Measured on a scale of 0-14 with 7 being neutral (pure water). It a ects the solubility of nutrients and heavy metals (Fe, Cu, etc) in water. It also determines the availability of these chemicals for the aquatic life eg: heavy metals more soluble in basic (corrosive) waters, therefore an increase in pH can lead to higher concentrations of heavy metals, which could be dangerous for aquatic life. In natural water systems, it is dependent largely on the geology and soil of the area under study.Most marine plants and animals are sensitive to pH variations. The pH of Water is a ected by the minerals dissolved in the water, aerosols and dust from the air, and human-made wastes and the pH between 6.5 and 8.5 is generally suitable (Figure 7.5). It can be measured using the pH meter following 4500-H+ B Electrometric method (Table 7.5). Calibration of electrode should be done at least once per day, before the pH measurement of the sample. The calibration is generally performed using 4, 7 and 9.2/10 pH bu er solutions. Once calibrated, the pH meter can be used to measure the pH directly by placing the electrodes in a water sample immediately after it is obtained. The pH measurement involves di usion of H+ ions across the glass membrane (part of electrode as shown in gure 7.6). The Di usion rate is proportional to the pH of the solution. Care should be taken to ensure that the electrodes are rinsed with distilled water before and after each determination and that it is place in electrode cap, containing distilled water or any recommended electrolyte, while not in use. 108

Water Quality A ssessment Core Parameters (9) Field Observations (7) pH Weather Temperature Approximate depth of main stream/depth of water table Conductivity Colour and instensity Dissolved Oxygen Odor Biochemical Oxygen Visible euent discharge Nitrate-N Human activities around station Nitrite-N Station detail Faecal Coliform Total Coliform Bio-Monitoring Parameters (3) Saprobity Index General Parameters (19) Diversity Index P/R Ratio COD Chloride TKN Sulphate Trace Metals (9) Ammonia Total Alkalinity Arsenic Nickel Copper Mercury Chromium Total Total Dissolved Solids P-Alkalinity Cadmium Zinc Lead Iron Total Total Fixed Solids Phosphate Total Suspended Solids Sodium Pesticide (7) Turbidity Potassium BHC(Total) Dieldrin Carbamate 2.4 D Hardness Calcium DDT(Total) Aldrin Endosulphan Fluoride Magnesium Boron Figure 7.4 : Parameters monitored under the national programme for monitoring water quality Several factors a ect the pH of the water, including algal blooms, bacterial activity, water turbulence, chemicals owinginto the waterbody, sewage overows and impacts from land pollution, accidental spills, and acid rain. The pH of water is critical to the survival of most aquatic plants and animals. Many species have trouble surviving if pH levels drop under 5.0 or rise above 9.0. The pH values between 7.0 and 8.0 are optimal for supporting a diverse aquatic ecosystem. 109

Water Quality A ssessment Figure 7.5 : pH ranges for di erent types of water resources Figure 7.6 : pH electrode Temperature The temperature of water a ects its density, gas solubility, rate of chemical reaction occurring in water, growth rate of the aquatic lives, it's conductivity, pH and dissolved oxygen (Figure 7.7). So, its measurement is important for understanding various processes involved. It can be measured by directly dipping the thermometer in the natural body of water being studied. If direct measurement is not possible then the water sample can be taken in a plastic or glass beaker and then the temperature may be measured using thermometer. The temperature should be represented in °C with one digit after the decimal point (e.g. 13.2°C). The temperature of water can be changed due to various factors, which can be natural or articial cause. It can vary naturally due to changes in seasonal/diurnal air temperature, thermal stratication in lakes, size and temperature of inows and residence time (in case of lakes) etc. Unnatural causes might be the release of heated industrial e uent directly into the water bodies or deforestation etc. 110

Water Quality A ssessment Electrical Conductivity (EC) It is the ability of a substance to conduct an electrical current. It can be measured using eld based or tabletop EC meter (Figure 7.8) following 2510 B Electrode method (Table 7.5). Typically, the meter probe has two electrodes that are placed in the water sample solution to measure the conductance of electricity between them. The unit of EC is μS/cm or mS/m (S=Siemens). Its value in most natural waters range between 10-1000 μS/cm.Salts or other chemicals, that can be easily dissolved in water, can break down into positively and negatively charged ions. These free ions in the water conduct electricity, so the electrical conductivity of water depends on the concentration of ions. Salinity and total dissolved solids (TDS) are used to calculate the EC of water, which helps to indicate the line purity of water. The purer the water the lower the conductivity. EC is reciprocal of electrical resistance and indicates the presence of cations (K+, Na+, Ca2+….) and anions (Cl-, HCO3-, SO42- …).Conductivity of natural waters depends upon the ion characteristics (mobility, valence, concentration), water temperature, geology of the area where water is present, size of watershed, evaporation etc. Some articial factors such as wastewater e uents, urban runo , agricultural waste can also a ect the conductivity. Figure 7.7 : Water quality parameters a ected due to temperature Source: Fondriest Environmental, Inc. “Water Temperature.” Fundamentals of Environmental Measurements. 7 Feb. 2014. Water contains di erent types of solids such as total dissolved solid (TDS) and total suspended solids (TSS). Conductivity and TDS are approximately related a factor 0.67 is a widely accepted value but it depends on the dissolved constituents. In general TDS (mg/L)~ [0.55 to 0.7] x conductivity (μSiemens/cm). 111

Water Quality A ssessment (a) (b) Figure 7.8 : (a) and (b) Multi-ion analyzers Dissolved oxygen (DO) It is the amount of oxygen dissolved in water and available for sh and other aquatic life. It indicates health of an aquatic system. The value of dissolved oxygen (DO) ranges from 0- 18 ppm. Most natural water systems require 5-6 ppm to support a diverse population. DO content varies with time of the day, weather, temperature. The concentration steadily declines during the night and are the lowest just before dawn, when photosynthesis resumes. Other sources of oxygen include the air and inowing water sources. More oxygen dissolves into water when wind stirs the water. Rivers and streams deliver oxygen, especially if they are turbulent. Turbulence mixes water and air (aeration). The solubility of oxygen and other gases decrease with the increase in temperature. This means that colder lakes and streams can hold more dissolved oxygen than warmer waters. If water is too warm, it will not hold enough oxygen for aquatic organisms to survive. If yearly comparisons are made on dissolved oxygen levels, they should be done at the same time of day, during the same season and on a day with a temperature variation of only 10 degrees Celsius from the previous reading. Biological Oxygen Demand (BOD) Every clean water resource contains small amount of dissolved oxygen, up to about ten molecules of oxygen per million of water, which is a crucial component of natural water bodies; the presence of a su cient concentration of dissolved oxygen is critical for maintaining the aquatic life and aesthetic quality of streams and lakes. Oxygen demand is a measure of the amount of oxidizable substances in a water sample that can lower DO concentrations. The decay of organic matter in water is measured as biochemical oxygen demand (BOD). It represents the amount of oxygen consumed by bacteria and other microorganisms while they decompose organic matter under aerobic (oxygen is present) conditions at a specied temperature. BOD is used, often in wastewater-treatment plants, as an index of the degree of organic pollution in water. 112

Water Quality A ssessment The biochemical oxygen demand (BOD) is an empirical test, in which standardised laboratory procedures are used to estimate the relative oxygen requirements of wastewaters, e uents and polluted waters. Microorganisms use the atmospheric oxygen dissolved in the water for biochemical oxidation of organic matter, which is their source of carbon. The BOD is used as an approximate measure of the amount of biochemically degradable organic matter present in a sample. The 5-day incubation period (5210 B- 5-day BOD Test) has been accepted as the standard for this test (although other incubation periods are occasionally used (APHA, 2005) (Table 7.5). Nitrate and nitrite nitrogen Nitrate and nitrite are naturally occurring ions that are part of the nitrogen cycle. The nitrate ion (NO3−) is the stable form of combined nitrogen for oxygenated systems. Although chemically unreactive, it can be reduced by microbial action. The nitrite ion (NO2−) contains nitrogen in a relatively unstable oxidation state. Chemical and biological processes can further reduce nitrite to various compounds or oxidize it to nitrate. It is produced in nature by the microbial decomposition of fertilizers, plants, manures or other organic residues. Articial sources are livestock, manure/urine, failing septic systems, synthetic fertilizers. It can lead to eutrophication of natural water systems (overproduction of vegetation). Nitrate and nitrite ions present in the water sample can be measured following 4500-NO3- D Nitrate electrode method and 4500-NO2- B- Colorimetric method respectively (APHA, 2005) (Table 7.5). General parameters Turbidity It indicates total suspended solids (TSS) present in water. Its value represents mineral fraction, organics, inorganic, soluble organic compounds, plankton, microscopic organisms etc. The unit of turbidity is JTU (Jackson Turbidity Unit) or FTU (Formazin Turbidity Unit or NTU (Nephelometric turbidity units). Turbidity is generally caused phytoplankton, organic detritus from stream and/or wastewater discharges, dredging operations, channelization, increased ow rates, oods etc. The turbidity can be measured either through Secchi disk (Figure 7.9 (b)), where sechhi disk transparency is analysed by dipping it into the water, or through turbidity meter which measures the light scattered at 90° angle (Figure 7.9 (a)). 2130 B- Nephelometric method is the standard method used for the measurement of turbidity in water sample (APHA, 2005) (Table 7.5). 113

Water Quality A ssessment (a) (b) Figure 7.9 : (a) Flow diagram of turbidity meter; (b) Sechhi disk Hardness It is the traditional measure of the capacity of water to react with soap as hard water needs more soap to produce a lather. Hard water often produces a noticeable deposit of precipitate (e.g. insoluble metals, soaps or salts) in containers, including “bathtub ring” (Figure 7.10). Hardness is most expressed as milligrams of calcium carbonate equivalent per litre (me/L). The principal natural sources of hardness in water are dissolved polyvalent metallic ions from sedimentary rocks, seepage and runo from soils. Calcium and magnesium, the two principal ions, are present in many sedimentary rocks, the most common being limestone and chalk.a minor contribution to the total hardness of water is also made by other polyvalent ions, such as aluminium, barium, iron, manganese, strontium and zinc. Water hardness is generally measured following 2340 C titrimetric method (APHA, 2005) (Table 7.5). Figure 7.10 : Deposits on pipelines and taps due to hard water 114

Water Quality A ssessment Alkalinity Alkalinity refers to the capacity of water to neutralize acid, which is also commonly known as “bu ering capacity”. This capacity is mainly inuenced by how much carbonates and bicarbonates (H2CO3, HCO3, and CO3) are in the water solution. The main source of alkalinity in water is calcium carbonate (CaCO3), which are derived from carbonate rocks (limestone). Water alkalinity has a signicant e ect on the pH of the water. If the water alkalinity is high, it is very di cult to adjust the water pH to the right range, because the bu ering capacity of the water itself is very strong. Water alkalinity is generally reported as milli-equivalent per litre (me/L) or parts per million (ppm) of equivalent calcium carbonate. One me/L of alkalinity is equal to 50 ppm of equivalent calcium carbonate.Alkalinity can be measured following 2320 B titration method (APHA, 2005) (Table 7.5). Chemical oxygen demand (COD) Chemical Oxygen Demand or COD is a measurement of the oxygen required to oxidize soluble and particulate organic matter in water under specic conditions of oxidizing agent, temperature, and time. It is expressed in the unit mg/L which indicates the mass of oxygen consumed per litre of the solution. The quantity of oxidant consumed is expressed in terms of its oxygen equivalence. The chemical oxygen demand (COD) of a wastewater is measured in terms of the amount of potassium dichromate (K2Cr2O7), work as an oxidant, reduced by the sample during 2 hr of reux in a medium of boiling, 50% H2SO4 and in the presence of aAg2SO4 catalyst (APHA5220 B. Open Reux Method; Table 7.5). Ammonical-nitrogen Ammonia is a colourless, pungent gaseous compound of hydrogen and nitrogen that is highly soluble in water. It is a biologically active compound found in most waters as a normal biological degradation product of nitrogenous organic matter (protein). It also may nd its way to ground and surface waters through discharge of industrial process wastes containing ammonia and fertilizers.Un-ionized ammonia is the toxic form and predominates when pH is high (>8.0).The ammonium ion (NH4+) ion is relatively non-toxic and predominates when pH is low. In general, less than 10% of ammonia is in the toxic form when pH is less than 8.0 pH units. This proportion increases dramatically as pH increases. Ammonical nitrogen content in water sample can be measured through APHA 4500-NH3 C- Titrimetric method (Table 7.5)(APHA, 2005). Major cations (calcium, magnesium, sodium, and potassium) The calcium (Ca+2), magnesium (Mg+2), sodium (Na+) and potassium (K+) ions are generally dissolved from solids and rocks. The sources of Ca+2 and Mg+2 ions are limestone, dolomite, and gypsum. It causes most of the hardness and scale-forming properties of water. Calcium and magnesium are the principal cause of the formation of scale in boilers, water heaters, and pipes, and to the objectionable curd in the presence of soap. These mineral constituents and hardness greatly a ect the value of water for public and industrial uses. The sodium (Na) and potassium (K) ions are also found in ancient brines, sea water, some 115

Water Quality A ssessment industrial brines, and sewage. Large amounts (500 ppm or more) in combination with chloride give a salty taste. High sodium content commonly limits use of water for irrigation. Compounds of sodium and potassium are abundant in nature and highly soluble in water. Some groundwater that contains moderate amounts of dissolved material may, in passing through sodium- and potassium-containing rock formations, undergo base exchange and become soft at greater depths. The calcium (Ca+2), magnesium (Mg+2), sodium (Na+) and potassium (K+) ion concentration in water sources can be measured using APHA 3500-Ca B EDTA Titrimetric method, 3500- Mg B Calculation method, 3500-Na B Flame photometric method, and 3500-K B Flame photometric method respectively (APHA, 2005) (Table 7.5). These can also be measured using high end methods using ion chromatography, ICP-AES etc., in the laboratory. Major anions (chloride, uoride, sulphate) The major anions such as chlorides (Cl-), uoride (F-), sulphate (SO4-2) are dissolved from rocks and soils. The major sources of uoride is uorspar and cryolite while that of sulphate are gypsum, iron sulphides, and other sulfur compounds. The chloride ions are present in sewage and found in large amounts in ancient brines, sea water, and industrial brines, which increases the corrosiveness of water when present in large quantity. In combination with sodium, chloride ions give a \"salty\" taste to the water. Drainage from salt springs and sewage, oil elds, and other industrial wastes may add large amounts of chloride to streams and groundwater reservoirs. The sulphate ions present in water containing calcium forms a hard scale in steam boilers. The chlorides (Cl-), uoride (F-), sulphate (SO4-2) ions), present in water, can be measured using APHA 4500-Cl- B Argentometric method, 4500-F- C Ion selective electrode method, and 4500-SO42- E Turbidimetric method (APHA, 2005), respectively (Table 7.5). Total dissolved solids (TDS) The total dissolved solids (TDS) are solids in water that can pass through a lter (usually with a pore size of 0.45 micrometres). It is the measurement of the amount of materials dissolved in water. These materials can include di erent ions such as carbonate, bicarbonate, chloride, sulphate, phosphate, nitrate, calcium, magnesium, sodium, organic ions, and other ions which are generally released from rocks and soils. The amount and character of dissolved solids depend on the solubility and type of rocks with which the water has been in contact. A certain level of these ions in water is necessary for aquatic life. However, if TDS concentrations are too high or too low, the growth of many aquatic life can be limited, and death may occur. Water containing more than 1,000 ppm of dissolved solids is unsuitable for many purposes. The taste of the water often is a ected by the number of dissolved solids. High concentrations of TDS may a ect taste adversely and deteriorate plumbing and appliances. It can be measured using APHA method 2540 C (APHA, 2005) (Table 7.5). 116

Water Quality A ssessment Total suspended solids (TSS) The total suspended solids (TSS) is the portion of ne particulate matter that remains as suspension in water. It measures an actual weight of particulate matter for a given volume of sample (usually mg/l). The total suspended solids (TSS) are particles that are larger than 2 microns found in the water column. Most suspended solids are made up of inorganic materials, though bacteria and algae can also contribute to the total solid concentration. High TSS can block light from reaching submerged vegetation. As the amount of light passing through the water is reduced, photosynthesis slows down. Reduced rates of photosynthesis cause less dissolved oxygen to be released into the water by plants. If light is completely blocked from bottom dwelling plants, the plants will stop producing oxygen and will die. As the plants are decomposed, bacteria will use up even more oxygen from the water. Low dissolved oxygen can lead to killing of sh. High TSS can also cause an increase in surface water temperature, because the suspended particles absorb heat from sunlight. This can cause dissolved oxygen levels to fall even further (because warmer waters can hold less DO) and can harm aquatic life in many other ways. It can be measured usingAPHA2540 B methods. (Table 7.5) Table 7.5 : Methods used for the measurement of major water quality parameters (A PHA , 2005) S.No. Parameter/Ion/Element APHA Method used 1 Alkalinity 2320 B Titration method 2 Ammonia-N 4500-NH3 C- Titrimetric method 3 Biological Oxygen Demand 5210 B- 5-Day BOD Test 4 Calcium 3500-Ca B EDTA Titrimetric method 5 Chloride 4500-Cl- B Argentometric method 6 Chemical Oxygen Demand 5220 B. Open Reux Method 7 Conductivity 2510 B Electrode method 8 Fluoride 4500-F- C Ion selective electrode method 9 Hardness 2340 C Titrimetric method 10 Magnesium 3500- Mg B Calculation method 11 Nitrate-N 4500-NO3- D Nitrate electrode method 12 Nitrite-N 4500-NO2- B- Colorimetric method 13 pH 4500-H+ B Electrometric method 14 Potassium 3500-K B Flame photometric method 15 Sodium 3500-Na B Flame photometric method 16 Sulphate 4500-SO42- E Turbidimetric method 17 Turbidity (NTU) 2130 B Nephelometric method 18 Total dissolved solid (TDS) 2540 C. Total Dissolved Solids Dried at 180°C 19 Total suspended solid (TSS) 2540 B. Total Solids Dried at 103–105°C 117

Water Quality A ssessment Conclusion Water quality assessment is an important part of water monitoring as it helps the water quality managers and planners to set water quality targets and design suitable restoration programs for various water bodies. The chapter is an e ort to deliver the knowledge of water quality assessment to the researchers and other stakeholders. It is expected that the chapter will be useful for them for designing their water monitoring and assessment work. Disclaimer This is a training material for the participants of the Green Skill Building Program and parts in this chapter is taken from the mentioned sources and is not used for any commercial purpose except for educational one. References APHA (2005). Standard Methods for the Examination of Water and Wastewater. 21stEdition, American Public Health Association/American Water Works Association/WaterEnvironment Federation, Washington DC. Bartram J, Mäkelä A and Mälkki E (1 996). Field work and sampling. In Water qualitymonitoring: a practical guide to the design and implementation of freshwater qualitystudies and monitoring programs/ edited by Jamie Bartram and Richard Ballance. ©UNEP/WHO, London: E & FN Spon. h_ps://apps.who.int/iris/handle/10665/41851 ISO (2018). Water quality- sampling- part 3: Preservatives and handling of water samples. ISO 5667-3. IS 10500: (2012). Drinking water- specication BIS, New Delhi. Meybeck M and Helmer R (1989). The quality of rivers: from pristine state toglobal pollution. Paleogeog. Paleoclimat. Paleoecol. (Global Planet. Change Sect.), 75, 283- 309. Timmerman J G, Adriaanse M, Breukel R M A, Oirschot M C M, Ottens J J (1997).Guidelines for water quality monitoring and assessment of transboundary rivers. European water pollution control, 7 (5), 21-30. WHO (2013). Planning of water quality monitoring system. © WorldMeteorological Organization, Geneva, Switzerland. Further Reading Chapman, D (1996). Water Quality Assessments. A Guide to the Use of Biota, Sediments and Water in Environmental Monitoring. 2nd edition. Chapman & Hall, London. Bartram J and Ballance R (1996). Water Quality Monitoring - A Practical Guide to the Design and Implementation of Freshwater Quality Studies and Monitoring Programmes. © UNEP/WHO 118

Water Quality A ssessment Guidelines for Water Quality Monitoring (MINARS/27/2007-08). Central Pollution Control Board, Government of India. ISO 5667-3 (2018). Water quality — Sampling — Part 3: Preservation and handling of water samples. 119

8 INDICATOR BACTERIA IN WATER MONITORING Anita Pandey Abstract Water pollution refers to the contamination of water bodies, such as rivers, lakes, oceans, ground water, etc., that usually results from a range of human activities. Rivers have always been the most important resources of fresh water; most developmental activities depend upon them. Rivers play a major role in assimilating or carrying industrial and municipal wastewater, manure discharge and runo that are responsible for river pollution. It is important to study the status of pollution of the rivers in relation to various anthropogenic activities as rivers are the major source of drinking water. Indicator bacteria have been used to suggest the presence of pathogenic microorganisms in water. Coliform bacteria in general, and Escherichia coli in particular, are considered as the best indicators of water quality. Keywords: Water pollution; Microbial contamination; Indicator bacteria; Pathogenic bacteria; Bacteriological analysis; Coliforms, Escherichiacoli Introduction Aquatic microorganisms and their activities are of great importance in many ways. They (i) may a ect the human health and other animal life, (ii) occupy a key position in the food chain by providing nourishment for the next higher level of aquatic life, and (iii) are instrumental in the chain of biochemical reactions that accomplish recycling of elements, e.g., mineralization. Expanding human population, industrialization, agricultural practices, and discharges of wastewater into rivers have led to the deterioration of water quality. These intense anthropogenic practices have resulted in the loss of self-purication capacity of the water bodies (Sood et al. 2008; Nautiyal 2009). In this background, the freshwater ecosystems are considered as endangered and threatened worldwide (Dudgeon Anita Pandey, Ph.D. Department of Biotechnology, Graphic Era (Deemed to be University), Bell Road, Clement Town, Dehradun 248002, Uttarakhand, India [email protected]; [email protected] Monitoring and A ssessment of Environmental Parameters Eds. V. A gnihotri, S. Rai, A . Tiwari, S. Mukherjee, K. Kumar, R. Joshi, GBPNIHE, A lmora, Uttarakhand, India ©GBPNIHE 2020 120

Indicator Bacteria in Water Monitoring et al. 2006). Therefore, the conservation and sustainable use of freshwater resources has become a major concern in the present times (Hahn 2006). Natural water bodies often receive a variety of contaminants due to release of inadequately treated wastewater into them. Introduction of contaminants into the natural environment results in water pollution. This can lead to the pollution of aquatic ecosystems and simultaneously cause public health problems for the people living downstream. Use of this polluted water for drinking and many other domestic purposes or irrigation is the major cause of occurrence of the waterborne diseases worldwide. The relevance of waterborne diseases due to the presence of microbial contaminants, accounting to the spread of a variety of diseases, has been realized (Pruss et al. 2002; WHO 2015, 2018). The abundance, diversity, and types of microorganisms present in water is used as indicators of water quality (Okpokwasili andAkujobi 1996). Microbial Contamination of Water Microbial contamination of water is a serious environmental problem. It adversely a ects the human health and the associated biodiversity in aquatic ecosystems. Illness derived from chemical contamination of drinking water supply system is negligible as compared to the health problems due to microbial contamination. The most common and deadly disease-causing pollutants of biological origin in drinking water includes pathogenic bacteria, viruses, and protozoa. Waterborne diseases, including a range of gastrointestinal illnesses, are caused by a variety of microorganisms. It largely refers to the infections that predominantly are transmitted through consumption of contaminated water. The drinking water contaminated by human or animal faeces, who are either active cases or the carriers of pathogens, contain disease causing or pathogenic microorganisms. The detection and enumeration of indicator bacteria are of primary importance for monitoring sanitation and the microbiological quality of water. Vast majority of diarrheal diseases are attributed to contaminated water and poor sanitation. WHO (World Health Organization) has estimated that up to 80 % of all the sickness and diseases, and 30 % of deaths in developing countries worldwide are caused by poor hygiene, inadequate sanitation, and polluted or unavailability of water. Discharge of wastewaters in fresh waters and costal seawaters is the major cause of the presence of faecal microorganisms, including pathogens (WHO 2008). The waterborne diseases mainly include cholera, salmonellosis, malaria, shigellosis, hepatitis A, dengue, leptospirosis, and typhoid (Table 8.1). 121

Indicator Bacteria in Water Monitoring Table 8.1 : Main water-borne bacterial diseases (Cabral 2010) Disease Causal organism Cholera Vibrio cholerae Gastroenteritis Vibrio parahaemolyticus Typhoid fever and other Salmonella enterica subsp. enterica serovar Paratyphi salmonellosis Salmonella enterica subsp. enterica serovar Typhi Salmonella enterica subsp. enterica serovar Typhimurium Bacillary dysentery or Shigella dysenteriae shigellosis Shigella exneri Shigella boydii Acute diarrheas and Shigella sonnei gastroenteritis Escherichia coli Indicator Bacteria Coliforms Microbiological quality of drinking water is usually expressed in terms of occurrence of particular species of bacteria and is largely relies on monitoring of the indicator bacteria such as coliforms. Water is usually tested either for the presence of the total coliforms or for the presence of faecal coliforms. Human faecal matter is likely to contain enteric pathogens, therefore it is generally considered a risk for the human health (Scott et al. 2003; APHA 2012). Among coliforms, Escherichia coli- a member of faecal coliform group, is a preferred indicator of faecal contamination as compared to other faecal coliforms. During 1890s, it was considered as an indicator of water treatment safety. In further advancement (in late 1980s), analysis of E. coli, and simultaneously total coliforms, became inexpensive and simple technique in water contamination monitoring and hence re-inserted in the drinking water regulations. Depending on the environmental conditions, E. coli can survive in drinking water up to 4-12 weeks (Edberg et al. 2000). Relationship between bacterial species including E. coli O157:H7, Legionella, Pseudomonas, and Shigella, with waterborne diseases in recreational fresh waters has been studied (Hlavsa et al. 2011). The international or national guidelines provide the permissible values for the presence of contaminants in drinking water. As per the WHO guidelines, the level of E. coli or thermotolerant bacteria should be zero in a 100 ml sample of water directly intended for drinking or in treated water entering a distribution system (WHO 2015). However, Bureau of Indian Standards allows the presence of 10 coliforms/100 ml in drinking water (BIS 1991; 2012). WHO states 'Water must be examined regularly and frequently because pollution is often intermittent and may not be detected if examination is limited to one or only a small number of samples. For this reason, it is better to examine drinking water frequently by means of a simple test rather than less often by several tests or a more complicated test.' It further states 122

Indicator Bacteria in Water Monitoring that 'Examination for faecal indicator bacteria in drinking water provides a very sensitive method of quality assessment'. In this perception, E. coli best fulls these conditions as it is present in high numbers in the faeces of all the mammals and does not appreciably multiply in the environment outside its host. Furthermore, improved methods for detection of E. coli have been developed which are fast, sensitive, specic, and easy to perform (WHO 2015,2018). BacteriologicalAnalysis of Water Samples The practical approach to enumerate the presence of bacterial contaminants in water is to test for indicator bacterial species that would signal the faecal contamination. The indicator organisms must be (1) present in large numbers in normal faecal matters of humans and other warm blooded animals, (2) easy to isolate and enumerate, (3) more resistant to disinfection in comparison to the pathogens, and (4) generally absent in other sources. Coliform organisms, E. coli in particular, are close to these parameters (Gadgil 1998).While routine basic microbiological analysis of drinking water for testing the presence of E. coli is proposed by culture methods, simultaneous testing of faecal coliforms is suggested with the quantication of enterococci (Cabral 2010). In this background, the methods recommended for routine bacteriological testing of water samples are summarized in the following section. Most probable number (MPN) method For determination of coliforms, ve test tubes containing 10 ml of double strength lactose broth and 10 test tubes containing single strength lactose broth with Durham's tubes are taken. The water samples are inoculated in each lactose broth tubes i.e. 10 ml water sample into each ve tubes containing 10 ml double strength lactose broth, 1 ml water sample into ve tubes containing 5 ml single strength broth, and 0.1 ml water sample into each 5 tubes containing 5 ml single strength lactose broth. All the test tubes are incubated at 37°C for 48 h. Following incubation, all the tubes are observed for acid and gas production. The production of acid and gas indicate the presence of coliforms and thus test is considered positive. Loop full culture from tubes showing positive results are inoculated in Eosin-methylene blue (EMB) and Endo agar, and inoculated at 37°C for 24 h. For further determination of faecal coliforms (FC) and faecal streptococci (FS), lactose fermenting and non-fermenting colonies are isolated from MPN tubes, loop full of culture from tubes of MPN test are inoculated into Brilliant green bile and MUG-EC broth, respectively, and incubated at 44.5°C for 24 h. Standard plate count (SPC) method This method involves serial dilutions of the sample (1:10, 1:100, 1:1000, etc.) in sterile water followed by plating and incubation on prescribed agar media. Typical media include Nutrient agar for a general count and MacConkey and Endo agar for Gram-negative bacteria such as E. coli. Results are recorded as colony forming units (CFU) following 48 h of incubation at 37°C. 123

Indicator Bacteria in Water Monitoring Membrane filter technique (MFT) In this method, 100 ml water sample is placed through thin sterile membrane lter (pore size 0.45 μm) that is kept in a special lter apparatus contained in a suction ask. The lter disc containing the 'trapped' microorganisms are transferred to a sterile Petri dish having an absorbent pad saturated with a selective liquid medium (FC and Endo broth). Number of colonies, developed following incubation at 37°C for 24 h, are recorded. Number of coliforms per 100 ml of water sample are calculated by the formula=colony count/volume of sample used × 100. Case Studies The Himalayan rivers make crucial source of water under mountain ecosystem. The mountain streams generally contain few organisms at the source but as they ow into lower areas, especially those having large amounts of organic material, the number and types of organisms increase. Some are accidental contaminants while others are aquatic organisms. In countries like India, assessment of these water resources is essential with respect to the various kinds of anthropogenic activities. River Ganga, the largest river of Indian subcontinent, has its origin in the state of Uttarakhand. Bhagirathi and Alaknanda, the two major tributaries, merge at Dev Prayag to form river Ganges. It supports nearly 700 cities through its waterways (Verghese and Iyer 1993), while its basin accommodates 40% of Indian population leading to development of major cities along the bank of Ganges (Jin et al. 2015). Heavy sewage and industrial e uent discharge in the river leads to signicant deterioration of water quality a ecting the river ecosystem adversely (Yadav and Pandey 2017). A detailed study was conducted on Gangetic river system of Uttarakhand for water quality along with bacteriological parameters by Sood et al. (2008). The bacteriological analysis included total viable counts, total coliforms, and faecal streptococci. The gene pool obtained from this study indicated the immense bacterial diversity under the inuence of severe anthropological activities. This study conrmed the presence of bacterial indicators of faecal origin at various altitudes under Gangetic river system. The bacterial genera isolated and identied included Enterobacter, Proteus, Staphylococcus etc. Enumeration of high E. coli counts indicated the presence of pathogenic microbes of intestinal origin. These organisms, although, are not considered as indicator of pollution, their dominance suggest the probability of considering these organisms as indicator organisms in water pollution projects. More recently, analysis of bacterial communities of river Ganges, performed using next generation sequencing, highlighted the impact of anthropogenic activities on bacterial community composition of the Ganges (Jani et al. 2018). The cited study revealed the taxonomic variability in the bacterial community across the sites with accumulation of Firmicutes (20.9%), Verrucomicrobia (6.09%), Actinobacteria (4.51%), and Synergistetes (1.16%), at rural site while Proteobacteria (49.4%) and Bacteroidetes (12.7%) predominate the urban sites. 124

Indicator Bacteria in Water Monitoring On similar lines, bacteriological analysis of water samples collected from the river Jataganga, located at a pilgrim town in district Almora of Uttarakhand, showed the presence of bacterial species belonging to the families Enterobacteriaceae (Citrobactor, Escherichia, Hafnia, Klebsiella, Salmonella and Serratia), Micrococcaceae (Micrococcus, and Staphylococcus), Pseudomonadaceae (Pseudomonas and Bacillaceae), representing the indicators of water pollution and bacterial pathogens responsible for waterborne diseases (Aishvarya et al. 2018). The river Jataganga represents a unique location surrounded by deodar (Cedrus deodara) forest and comprising a cluster of 124 stone temples (Figure 8.1). The place is observed for organizing a number of festivals round the year involving all kinds of anthropogenic activities. Frequent recording on bacteriophages on agar plates and isolation of species of Escherichia, other than E. coli, namely E. fergusonii and E. marmotae were remarkable ndings of this study. Besides, many of these species were psychrotolerant and pH tolerant in nature. Interesting reports emanated from the study that was conducted before and during the Kumbh Mela using advance molecular techniques (Jani et al. 2018). Kumbh Mela is one of the largest religious mass gathering events (MGE) involving bathing in rivers that is likely to inuence the biogeochemical balance of the river ecosystem. The cited study focused on the changes in bacterial communities of the Godavari river before and during the MGE, the association between the environmental parameters and the river bacterial assemblage, and identication of the source of invasive communities to the river ecosystem. The study resulted in approximately 37.5% loss in microbial diversity because of the anthropogenic activities during MGE. A signicant decrease in phyla viz. Actinobacteria, Chloroexi, Proteobacteria, and Bacteriodetes and substantial increase in prevalence of the phylum Firmicutes, along with nearly 130 fold increase in bacterial load was found to be of human origin. AB CD E Figure 8.1 : A &B. The Jageshwar temple complex and the river Jataganga- a site that experiences a variety of anthropogenic activities; C&D. Enumeration techniques- MPN and MFT, respectively; E. E. coli colonies showing typical metallic sheen. 125

Indicator Bacteria in Water Monitoring Green Skill Building Program (gsbp) Perspective Accessibility and availability of fresh clean water is essential for health, food production, and poverty reduction. It is crucial in economic development and social welfare. In this perception, the GSBP should include awareness programs on: Ÿ water resources that are used for drinking, domestic, and other purposes, such as, irrigation, etc. Ÿ importance of water quality with respect to soil, plant, animal, human, and climate health Ÿ importance of periodical monitoring of water resources for quality Ÿ knowledge on biological (bacteriological) indicators of water contamination Ÿ health problems (diseases) that may occur due to the use/consumption of contaminated water Ÿ easy-to-do steps to promote safe use of water Ÿ advisory on the use of water for various purposes Conclusion Human activities inuence the water resources in both structural and functional dimensions. The cited exemplary case studies, in this Chapter, are indicative of the necessity to examine the microbial communities associated with the water bodies under a set of climatic conditions and taking an account of the kind of anthropogenic activities. In planning of the water monitoring projects, an integrated approach including the role of indicator organisms, disease causing organisms, benecial organisms, their interactions among themselves and with the natural aquatic ora and fauna, and the seasonal and environmental parameters should be considered collectively. Besides, understanding on the role of bacteriophages with respect to the presence of a self-purication system will strengthen the water pollution and water monitoring programs. Studies on mass gathering events are likely to address the issues related to public health challenges, such as, transmission of infectious diseases. This will help in taking policy level decisions with a view on investments for research into prevention, surveillance, and management of these public health issues (Memish et al. 2018). However, individual countries should be encouraged to develop their guidelines that are technically and economically feasible. Periodical organization of workshops like “Monitoring of Environmental Factors and their Interpretation” under Green Skill Building Program will certainly bring awareness on the subject in common people. Acknowledgement Director and the Team Green Skill Building Program, GB Pant National Institute of Himalayan Environment, Almora, are gratefully acknowledged for extending the opportunity for theAuthor's participation in this awareness program. 126

Indicator Bacteria in Water Monitoring References Aishvarya N, Malviya MK, Tambe A, Sati P, Dhakar K, Pandey A (2018). Bacteriological assessment of river Jataganga, located in Indian Himalaya, with reference to physico- chemical and seasonal variations under anthropogenic pressure: A case study. Journal of Environmental Microbiology 1(1), 10-16. APHA (2012).Standard Methods for the Examination of Water and Waste Water, 22nd Edition. American Public Health Association, American Water Works Association and Water Environmental Federation, Washington DC. BIS (Bureau of Indian Standards) (1991). Drinking water-specication, Ist Revision. IS:10500. New Delhi. BIS (Bureau of Indian Standards) (2012). Drinking water-specication, 2nd Revision. IS:10500, New Delhi. Cabral JPS (2010). Water microbiology. Bacterial pathogens and water. International Journal of Environmental Research and Public Health 7, 3657-3703. Dudgeon D, Arthington AH, Gessner MO, Kawabata Z, Knowler DJ, Lévêque C, Naiman RJ, Prieur-Richard AH, Soto D, Stiassny ML, Sullivan CA (2006). Freshwater biodiversity: importance, threats, status and conservation challenges. Biological Reviews of the Cambridge Philosophical Society 81:163-182. Edberg SC, Rice EW, Karlin RJ, Allen MJ (2000). Escherichia coli: the best biological drinking water indicator for public health protection. Journal of Applied Microbiology 88, 106S-116S. Gadgil A (1998). Drinking water in developing countries. Annual Review of Energy and the Environment 23, 253-86. Hahn MW (2006). The microbial diversity of inland waters. Current Opinion in Biotechnology 217, 256-261. Hlavsa MC, Roberts VA, Anderson AR, Hill VR, Kahker AM, Orr M, Garrison LE, Hicks LA, Newton A, Hilborn ED, Wade TJ, Beach MJ, Yoder JS (2011). Surveillance for waterborne diseases outbreaks and other health events associated with recreational water- United States, 2007-2008. Morbidity and mortality weekly report (MMWR) Surveillance Summaries, 60, (12), 1-32. Jani K, Dhotre D, Bandal J, Shouche Y, Suryavanshi M, Rale V, Sharma A (2018). World's Largest Mass Bathing Event Inuences the Bacterial Communities of Godavari, a Holy River of India. Microbial Ecology, 75(3), 706-718 Jani K, Ghattargi V, Pawar S, Inamdar M, Shouche Y, Sharma A (2018). Anthropogenic activities induce depletion in microbial communities at Urban Sites of the River Ganges. Current Microbiology, 75, 79-83. 127

Indicator Bacteria in Water Monitoring Jin L, Whitehead PG, Sarkar S, Sinha R, Futter MN, Buttereld D, Caesarf J, Crossmangh J (2015). Assessing the impacts of climate change and socioeconomic changes on ow and phosphorus ux in the Ganga river system. Environmental Science- Processes & Impacts, 17, 1098-1110 Memish ZA, Ste en R, White P, Dar O, Azhar EI, Sharma A, Zumla A (2019). Mass gatherings medicine: public health issues arising from mass gathering religious and sporting events. Lancet, 393, 2073-2084. Nautiyal CS (2009). Self-puricatory Ganga water facilitates death of pathogenic Escherichia coli O157:H7. Current Microbiology 58, 25-29. Okpokwasili GC, Akujobi TC (1996). Bacteriological indicators of tropical water quality. Environmental Toxicology 11, 77-81. Pruss A, Kay D, Fewtrell L, Bartram J (2002). Estimating the burden of disease due to water, sanitation and hygiene at global level. Environmental Health Perspectives, 110, 537- 542. Scott TM, Salina P, Portier KM, Rose JB, Tamplin ML, Farra SR, Koo A, Lukasik J (2003). Geographical variation in ribotype proles of Escherichia coli isolates from human, swan poultry, beef, and dairy cattle in Florida. Applied and Environmental Microbiology 69(2), 1089-1092. Sood A, Singh KD, Pandey P, Sharma S (2008). Assessment of bacterial indicators and physicochemical parameters to investigate pollution status of Gangetic river system of Uttarakhand (India). Ecological Indicators, 8, 709-717. Verghese BG, Iyer RR (1993). Harnessing the Eastern Himalayan Rivers: Regional Cooperation in SouthAsia. Konark Publishers, New Delhi. World Health Organization (2008). Guidelines for Drinking-water Quality, Incorporating 1st and 2ndAddenda, Vol. 1, Recommendations, 3rd ed., Geneva, Switzerland. World Health Organization, International Water Association (2015). A practical guide to auditing water safety plans. ISBN: 978 92 4 150952 7. World Health Organization (2018).Aglobal overview of national regulations and standards for drinking-water quality. ISBN: 978-92-4-151376-0. YadavA, Pandey J (2017). Water quality interaction with alkaline phosphatase in the Ganga river: implications for river health. Bulletin of Environmental Contamination and Toxicology 99(1), 75–82. 128

9 BASICS OF GEOSPATIAL TECHNIQUES FOR INTERPRETATION OF HYDRO-ENVIRONMENTAL VARIABLES Ashutosh Tiwari, Santosh Murlidhar Pingale Abstract The researchers and decision-makers extensively use computer models to understand and cope up the various environmental and engineering problems. GIS and remote sensing can provide the geographic characteristics and represent spatial relationships of systems. High spatial resolution satellite imageries can provide the spatial data with ner details in visible, infrared and thermal regions of the electromagnetic spectrum. The microwave remote sensing can penetrate down the clouds to give information about subsurface features. Digital Elevation Model (DEM) datasets provide the topographical information of the region that helps to derive useful information such as the slope, aspect, watershed, etc. The combination of GIS and remote sensing with traditional mathematical and hydrological models are more advantageous for solving complex water resources and environmental problems. The purpose of this lecture note is to provide a general overview of remote sensing and GIS and how these technologies useful for di erent studies in monitoring and data interpretations in these areas. Keywords: Geospatial techniques, Remote Sensing, GIS, data interpretation Introduction The art, science, and technology of obtaining reliable information about physical objects and the environment, through the process of recording, measuring and interpreting imagery and digital representations of energy patterns derived from non-contact sensor systems called as remote sensing (Colwell, 1997). Recent advancement in remote sensing technology has Ashutosh Tiwari, M.Tech. Centre for Land and Water Resource Management GB Pant National Institute of Himalayan Environment, Kosi- Katarmal, Almora [email protected] Santosh Murlidhar Pingale, Ph.D. Hydrological Investigations Division, National Institute of Hydrology, Roorkee [email protected] Monitoring and A ssessment of Environmental Parameters Eds. V. A gnihotri, S. Rai, A . Tiwari, S. Mukherjee, K. Kumar, R. Joshi, GBPNIHE, A lmora, Uttarakhand, India ©GBPNIHE 2020 129

Basics of Geospatial Techniques for Interpretation of Hydro-Environmental Variables made it possible to capture the data at a resolution as good as 10 cm and even in some cases on a real-time basis (https://oceanservice.noaa.gov/facts/remotesensing.html). Electromagnetic Waves and Electromagnetic Spectrum The concept of Electromagnetic Waves (EMW) and Electromagnetic spectrum for illustration purpose adapted from CRISP, 2003.Electromagnetic Waves are energy transported through space in the form of periodic disturbances of electric and magnetic elds. An electromagnetic wave is a type of 'Tranverse wave' that is sinusoidal and resembles the dual nature of both Electric and Magnetic elds that oscillates in planes mutually perpendicular to each other. All electromagnetic waves travel through space at the same speed as the speed of light (i.e. c = 2.99792458 x 108 m/s), which is a product of frequency and wavelength (Figure 9.1). It characterizes an electromagnetic wave. The frequency of an electromagnetic wave depends on its source. There is a wide range of frequencies of EMW encountered in our physical world, ranging from the low frequency (High wavelength) radio waves used for telecommunication purposes to the very high frequency of the gamma rays originating from the atomic nuclei. This frequency range of electromagnetic waves constitutes the electromagnetic spectrum (Figure 9.2). This divided into several wavelength (frequency) regions, among which only a very narrow band of wavelength in the range of about 400 to 700 nm is visible to the human eyes (Figure 9.2) (CRISP, 2003). Figure 9.1 : Electromagnetic waves (Source: CRISP, 2003) Visible Light regionof electromagnetic radiation (EMR) extends from about 400 nm (violet) to about 700 nm (red). The VIBGYOR is the constituent of white light and lies in this band of spectrum in the order of increasing wavelength and decreasing frequency. The various VIBGYOR constituents of the visible spectrum fall roughly within the following wavelength regions (Table 9.1). Infrared region is divided into di erent bands ranging from 0.7 to 300 µm wavelength (Table 9.2). The NIR and SWIR are also known as the Reected Infrared, referring to the main infrared component of the solar radiation reected from the earth's surface. The MWIR and LWIR are the Thermal Infrared. The infrared band, however, is not sensitive to human eyes, yet plays a very crucial role in the eld of remote sensing for feature detection such as vegetation, water, snow, etc. (CRISP, 2003). 130