Waterose Environmental

Advanced Water Quality Techniques Course

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The development of a strategic water quality monitoring program is based on prioritizing risks to public safety and economic reality. The development of global standardized methods and protocols for automated water quality monitoring would facilitate international communication of water quality information and comparison of standardized methods and protocols. The three primary methods of water quality monitoring include discrete, mechanical and automated. There is a wide body of literature that publishes accepted standardized methods and protocols for discrete and mechanical methods of monitoring water quality. The case example discussed in this paper is based on the Automated Water Quality Monitoring Field Manual of British Columbia, Canada, which includes chlorophyll, conductivity, dissolved oxygen, pH, turbidity and water temperature. Quantitative defined methods and protocols rank the quality of the continuous time-series automated water quality monitoring data. The automated data are verified by a combination of water quality monitoring methods including verification with standard chemical solutions, field analysis and laboratory analysis. Quality assurance and quality control procedures determine the level of the quality of the data. There is a direct relationship between the quality of the data and the cost to obtain that data. Water quality monitoring data is transformed from raw data to finished data for publication to make important decisions that impact public health and public safety.

Strategic planning is essential to designing and implementing an effective water quality monitoring program. Having a strategic water quality monitoring program reduces uncertainty and enhances stability for economic activity. An effective plan must identify objectives, resources, and strategies to attain the objectives. There is a direct relationship between the accuracy of water quality monitoring data and the cost to obtain that information.

The primary objective of water quality monitoring is to deliver clean safe water. Clean fresh water is more precious than gold or oil because water is life.

Seven people died and twenty three hundred people became ill in the town of Walkerton, Ontario in May of 2000 because the drinking water became contaminated with a lethal strain of bacteria. This tragedy cost the government of Ontario $65 million to conduct the inquiry; the loss of life and suffering is estimated at an additional $91 million with costs totaling more than $156 million. This tragedy could have been prevented with an effective water quality monitoring program that included the use of continuous automated water quality monitoring.

The applications of water quality monitoring extend beyond the provision of safe clean drinking water. It is essential to monitor water quality in community watersheds that are used by multiple stakeholders and provide aquatic habitat. Water is a natural resource. Other natural resource industries can have an adverse impact on water quality including forestry, mining, and generating hydroelectric power. Water quality monitoring is an effective tool to assess the extent and remediation of contaminated sites, such as a spill zone or an abandoned mine.

The roles and responsibilities of primary stakeholders involved in water quality monitoring vary. The government is responsible to legislate standards, define methods and protocols, and enforce compliance. Industry consumes water, contaminates water, and must comply with standards set by government. The community is concerned with safe potable water and safe recreational water. The private sector provides services to treat and clean water to acceptable standards, to deliver water to consumers, and to monitor water quality. The non-governmental organizations provide volunteer services, monitor the performance of other stakeholders, and increase public awareness.

The water quality monitoring program is based on several factors. Priorities are based on risk. Budgets determine the scope and execution of the plan. Land use determines the variables that need to be monitored. Effective strategies, such as public-private partnerships and cost recovery incentives, can expedite the plan and reduce costs.

The water quality information or ‘data’ is retained as a permanent record, which includes supportive documentation and electronic records or data warehousing.

Water Quality Monitoring Methods:
There are three primary methods of water quality monitoring: discrete, mechanical, and automated. Discrete monitoring is the traditional manual method of taking a single measurement of water quality at the water body or obtaining a sample of water to send to a laboratory for analysis. Mechanical water quality monitoring is the method of leaving a container of sample bottles at the water body that mechanically obtain samples of water, which are later retrieved and sent to a laboratory for analysis. Automated water quality monitoring (AWQM) is the method of placing water quality sensors into the water body, which is continuously measured by the sensors and the information is stored in memory.

Consider this analogy: discrete water quality monitoring is like using a manual typewriter, mechanized water quality monitoring is like using an electric typewriter, and AWQM is like using a computer.

There are three types of AWQM stations: passive, active, and reactive. The passive station measures and records the information. The active station measures and records the information but can perform additional simple tasks, such as transmitting the information or providing information to a voice modem when it is triggered by a remote signal such as an internet inquiry. The reactive station performs the same functions as the passive and active, but has sophisticated programming that responds to the water quality conditions and can take action such as closing a drinking water valve or releasing chemicals to neutralize the water quality conditions.

The optimal water quality monitoring program will adopt the method that is most appropriate to meet the objectives. A combination of methods yields optimum water quality information.

International Water Quality Monitoring Standardized Methods:
Standardized methods and protocols for water quality monitoring are quintessential to obtain water quality information. International, national, and domestic standardized methods and protocols must be inherently based on a common language or set of standardized methods and protocols to facilitate communication and understanding of the information amongst parties. Standardization and harmonization is essential to draw comparisons to analyze which is the optimal method to meet the objectives of the water quality monitoring program.

The published standard methods and protocols for discrete and mechanized water quality monitoring include:

International Standards Organization (ISO). Water Quality Methods. Switzerland;
United States American Public Health Association. Standard Methods for the Examination of Water and Wastewater. USA;
United States Geological Surveys. National Field Manual for the Collection of Water-Quality Data. Techniques of Water - Resources Investigations. USA; and,
Canadian Council on Ministers of the Environment. Canadian Water Quality Guidelines. Canada;
The published standardized methods and protocols for AWQM include:

United States Geological Surveys. Guidelines and Standard Procedures for Continuous Water-Quality Monitors: Site Selection, Field Operation, Calibration, Record Computation, and Reporting. USA; and,
British Columbia Resource Inventory Committee Standards. Automated Water Quality Field Manual. British Columbia, Canada.
AWQM utilizes a combination of discrete methods and automated methods. Discrete methods are integral to automated methods. Mechanized methods could also be incorporated into AWQM methods to optimize water quality information.

Water Quality Monitoring in Canada:
The role of the government to develop standardized methods and protocols for water quality monitoring and enforce those guidelines, is shared between both the federal and provincial government in Canada.

The Constitution Act, 1867 of Canada delineates federal and provincial legislative powers. Section 91 establishes federal jurisdiction over seacoasts and inland fisheries. Section 92 and Section 109 establish provincial jurisdiction over natural resources, which includes water. Both levels of government monitor water resources.

At the federal level, the Department of Environment Canada (EC) and the Department of Fisheries and Oceans Canada (DFO) regulate and monitor water resources.

At the provincial level in British Columbia, several ministries monitor freshwater resources including the Ministry of Forests, Ministry of Water, Land and Air Protection and the Ministry of Sustainable Resource Management (MSRM).

MSRM develops and administers standardized methods and protocols for monitoring the environment and natural resources such as forestry, sensitive habitat, ground water and surface water resources. Automated monitoring standardized methods and protocols are developed for monitoring of water quality, water quantity, and meteorology.

Water Quality Monitoring in British Columbia:
The province of British Columbia is shifting from providing government water quality monitoring services to procuring water quality monitoring services from private industry. This shift towards privatization of water quality monitoring triggered the challenge to develop quantified and measurable standardized methods and protocols to quantify the water quality information obtained. In addition, there must be clearly defined project objectives, project costing, and a mechanism for the provincial government to determine that the project criteria are met. These principles are fundamental to water quality monitoring in British Columbia.

The Development of the AWQM Program in British Columbia:
Hence, a strategic plan was created to develop an AWQM program in British Columbia. The resources available to meet this objective were very limited, so consequently every opportunity was explored to reduce cost expenditures. The primary elements of the plan include: establishing a research and development station to test different equipment and different methods, develop quality assurance and quality control mechanisms, document results, publish results, develop and deliver training, certify private industry, and data warehousing.

The development of standardized methods and protocols is based on ‘normal’ pristine conditions, against which, comparisons are made for deviations from ‘normal’. One would compare water quality at a contaminated site against water quality at a pristine site to determine the measurable environmental impacts. Another option is to measure ambient water quality conditions against defined standards or maximum/minimum allowable concentrations.

The publication of standardized methods and protocols for AWQM in British Columbia is based on scientific methods developed at the research and development station. The research and development station is located on the Sooke River at 48°25’28'N and 123°42’45'W at the southern tip of Vancouver Island, west of Vancouver, Canada and north of Seattle, USA.

The standardized methods and protocols are published for AWQM of the water quality variables: chlorophyll, conductivity, dissolved oxygen, pH, turbidity, and water temperature.

Characteristics of the Study Area:
Vancouver Island is comprised of accreted terranes. The bedrock consists of metamorphic sedimentary and volcanic rock and igneous complex, sandstone, shale and conglomerates. The overlay consists of glacial and fluvial deposition. The dominant soils include brunisols and podzols of porous gravel and quartz sand with a slightly acidic signature. The dominant biogeomatic classification is Coastal Western Hemlock (Tsuga heterphylla), Western Red Cedar (Thuja plicata) and Douglas fir (Pseudotsuga menziesii). The climate is wet maritime with mild wet winters and warm dry summers with a mean annual precipitation of 50 inches or 1300 millimeters and a mean temperature of 48 degrees Fahrenheit or 9.1 degrees Celsius.

The Sooke River watershed area is 150 square miles or 400 square kilometers. The headwaters consist of the Leech River complex and the Sooke Lake, which provides the drinking water for the city of Victoria. Historically, the watershed has been logged and mined. The lower Sooke River lies in a floodplain that is rural residential with homes and small hobby farms. Other stakeholder interests include active timber harvesting, development, and the T’Sou-Ke First Nations.

The mean annual discharge of the Sooke River is 335 cubic feet per second or 9.5 cubic meters per second. The substrate is cobble, boulder and fines. The river supports freshwater fish species and anadromous salmon including Chum (Oncorhynchus keta), Chinook (O. tshawytscha), Coho (O. kisutch), and Steelhead trout (Salmo gairdneri). Wildlife includes deer, bear, cougar, small mammals, raptors such as bald eagles and waterfowl.

The Sooke River AWQM Station Design:
The AWQM station is a passive, angle-bank, deployment design. Other station design options include vertical tube deployment or side channel design. Two equipment system configurations have been deployed. System A, deployed from November 2000 to October 2001, was comprised of a Forest Technology Systems (FTS) data logger, Stevens vented pressure transducer, YSI 600XL multi-sonde that measured conductivity, dissolved oxygen, pH, and temperature, and an analite turbidity sensor with a mechanical wiper arm. System B, deployed in October 2001 and currently in operation, is comprised of a Handar 555 data logger, Stevens vented pressure transducer, YSI 6820 multi-sonde that measures conductivity, dissolved oxygen, pH, temperature and turbidity with a mechanical wiper arm. The data are logged in fifteen-minute intervals and retrieved manually.

The selection of the location of the station must be environmentally representative of ambient environmental conditions. This can be achieved by obtaining discrete water quality measurements of the ambient water quality under the full range of environmental conditions. The selected equipment must be capable of measuring both the normal ambient environmental conditions and the full range of ambient environmental conditions. The AWQM equipment and support equipment is based on the principle of best available technology (BAT); BAT refers to equipment that has been commercially produced and tested to optimum specifications and is available on the open market for a reasonable price.

The Sooke River AWQM Station Operation:
Station operation includes certification, bench testing, verification, and quality control and quality assurance (QA/QC). The AWQM equipment system components must be calibrated and certified by the manufacturer or authorized representative with the exception of dissolved oxygen, which must be calibrated on a regular basis. The AWQM system must be bench tested by the certified water quality monitoring technician prior to deployment. The AWQM sensors must perform within specified criteria, such as within 10% of a certified standard solution, prior to deployment. The certified AWQM technician completes regular visits to maintain the AWQM equipment and to verify the accuracy of the AWQM data that is recorded by the AWQM equipment.

The AWQM data can be verified by three methods, depending on the water quality variable that is being monitored. Not all methods are applicable to all variables. There is a direct relationship between the accuracy and precision of the method and the costs of that method.

First, the performance or drift of the AWQM sensors can be verified by measurements in certified standard solutions. This applies to verification of chlorophyll, conductivity, pH, and turbidity. The sensor must perform within 10% of the standard being measured. The performance of standards varies between manufacturers.

Second, the data of the AWQM sensors can be verified by comparison of measurements of ambient water quality between the AWQM sensors and field measurements by a different field method or a different field instrument. This applies to field comparison measurements of chlorophyll, conductivity, dissolved oxygen, pH, turbidity, and water temperature. The comparison field method of choice depends on the accuracy level of water quality data and is defined for each water quality variable by technical equipment competencies. Even so, the question remains 'Which meter?' Consequently, field meter comparisons are used only as a general comparison. It is prudent to select a field measurement method that is fundamentally different from the principles of operation of the AWQM sensors. For example, dissolved oxygen can be measured using a wide variety of stream-side methods including drop count titration, digital titration, colorimetric analysis, electrochemical meter, and barometric pressure calculations.

Third, the data of the AWQM sensors are verified by obtaining discrete surface water samples for laboratory analysis. This applies to obtaining water quality samples for laboratory analysis for chlorophyll, conductivity and turbidity. A sample is obtained adjacent to the automated water quality monitoring sensors in situ and verifies the data obtained by the AWQM sensors. Another sample is obtained from in situ mid-stream and is used as a measurement to determine if the AWQM are obtaining data that are representative of the environmental conditions of the water body.

The quality assurance and quality control requirements for additional samples such as duplicate samples, field blanks, trip blanks and laboratory blanks vary depending on the desired quality of data. The laboratory results are the primary basis to determine if the AWQM sensors are measuring data that are representative of the environment. The verification of the AWQM data by laboratory analysis is limited to variables that can be measured by laboratory analysis.

The AWQM sensors are vulnerable to specific interferences that may include bio-fouling, physical fouling, signal noise, optic damage, entrained gas bubbles, sunlight spikes, hydrodynamic noise, calibration drift, temperature effects, and power-up interference. Each potential interference must be taken into account in the system design, operation, maintenance, and data management.

Every step in the procedure is fully documented on standardized forms that include AWQM station location and site information, AWQM equipment certification and calibration, AWQM equipment bench testing, AWQM sensor verification (standards, meters, laboratory), and field maintenance visits.

Data Management:
The management of water quality monitoring data is changing with evolving computer, communications, and internet technologies.

Water quality monitoring data is comprised of individual discrete measurements taken in the field or from laboratory analysis, and AWQM time series data. Historically, the first generation of data management was a manual documented process. The next generation of record management was an autonomous computer based system. The current method is data warehousing, which is the brining together of autonomous computer databases under one umbrella, which is called the data warehouse. The data warehouse integrates environmental data, which includes water quality, water quantity and meteorological data.

The methods used to communicate water quality monitoring data are evolving from a manual method to satellite transmission of the data and everything in-between, which includes electronic retrieval in the field, radio transmission, telephone transmission, and internet technologies.

Internet technologies facilitate the input and retrieval of data to such a level that real time data, which includes both discrete and AWQM time series data, can be transmitted and viewed by using an internet interface.

Data correction transforms the AWQM data from raw time series data to finished data. The process must be documented. The process must rank the quality of the finished data, which reflects the confidence level in the data. The BC AWQM process ranks the AWQM time series data into four categories: A, B, C, and D with Grade A data being the highest quality level of data possible based on the methods used to obtain that data. Recall that there is a direct relationship between the quality of data and the costs to obtain that data. The United States Geological Surveys (USGS) process ranks the data based on percent deviation.

The AWQM time series data can be adjusted in three ways. First, there may be data gaps that must be accounted for. Second, the AWQM time series data may be corrected to account for AWQM sensor drift between regular maintenance and calibration corrections. Third, the AWQM time series data may be corrected to account for an environmental shift correction, which is a process used by the USGS.

Regardless of the details of the corrections to the AWQM time series data, both the raw AWQM time series data and the corrected AWQM time series data are retained in the data warehouse and adjustments are fully documented and accounted for. Uncorrected data must be identified as such. The USGS refers to uncorrected data as provisional data. This is particularly important for real time AWQM time series data that is published on the internet prior to making corrections to the AWQM time series data.

The AWQM time series data must be reviewed, approved, and audited to verity the quality and validity of that data, which is used by government, water quality managers, industry, and the public.

In British Columbia, the BC MSRM needs to undertake additional research and development to expand the standardized methods and protocols for AWQM of other important water quality variables such as ion specific electrodes for nutrients. The BC MSRM needs to develop and deliver the formal training to the private industry sector that undertakes the water quality monitoring activities. There are no formal legal requirements to use AWQM methods in British Columbia and the government of British Columbia needs to draft and enact legislation to incorporate AWQM methods into water quality monitoring of this valuable resource.

The Government of Canada needs to develop and publish national standardized methods and protocols for AWQM to facilitate communication using a common language and transfer of AWQM data between parties, such as AWQM data for a river that flows through more than one province and is monitored by more than one province.

AWQM is changing how we manage and monitor water. Globally, there are very few government publications about standardized methods and protocols for AWQM. To date, I have received expressions of interest in this work from Australia, Egypt, Switzerland and United States. We need an international conference to encourage scientific experts and governments to establish AWQM standardized methods and protocols for individual countries; otherwise, each country will be developing national standardized methods and protocols for AWQM data autonomously. A global conference would help facilitate transfer of information, experience, and technologies to develop a common language.

Water quality monitoring is evolving with emerging technologies. Population growth increases water consumption and the need for water quality monitoring as demonstrated by the Walkerton tragedy, which cost $156 million.

A strategic plan is quintessential to develop and to deliver an effective and safe water quality monitoring program.

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