Our natural ecosystems are made up of forests, wetlands, water sources, plants and animals, and provide multiple goods and services that contribute to a healthy economy, environment and people.
Every day, we rely on ecosystem goods and services - they connect us to our environment. Conservation Authorities deliver practical, cost effective programs that ensure healthy ecosystems which enable them to generate and maintain valuable goods and services, often preventing the need for costly technological solutions to environmental problems.
Skip to main content. Healthy Watersheds Protection. Contact Us. Benefits of Healthy Watersheds. These are typically complex problems that are difficult to manage. Both nonpoint pollution and habitat degradation generally cross program purviews. To establish a method to tackle these remaining problems managements must come together to better understand the interactions between the environmental components and the actions that can be taken by all towards the goal of ecosystem integrity.
West Virginia has over 9, streams covering 32, stream miles. Permits Programs Citizens Data About. Search Loading Performance criteria are typically included in local, regional, or state manuals.
Review and Inspection. Ensuring that the watershed protection practices are designed properly and installed correctly occurs in two stages. In the first stage, development plans are scrutinized in a local review process to ensure that they meet applicable performance criteria and are appropriate for the site. In the second stage, field inspections are conducted at the site to ensure that the practices have been installed or constructed according to the plan.
In the case of OSTDS, a developer might submit a plan for on-site wastewater disposal for local review, followed by an inspection at the site during construction to confirm that the system is installed properly and works as designed.
Structural and nonstructural practices must be continuously maintained in order to ensure effectiveness over time. Maintenance tasks for structural practices include routine pollutant cleanouts and rehabilitation of the practices as they approach the end of their design life.
With OSTDS, routine maintenance entails periodic cleanouts of the septic tank and repairs to the distri-. For nonstructural practices such as a conservation easement, maintenance can involve routine inspections and vegetative management measures. Each watershed practice requires a legally binding maintenance agreement that identifies the party responsible for future maintenance and clearly outlines maintenance tasks, costs, and schedules.
Compliance Enforcement. An enforcement authority is usually needed to ensure that all owners or developers are in compliance with watershed regulations or criteria. Enforcement may be needed in the event an owner avoids watershed requirements, fails to properly implement plans, or does not adequately maintain a practice.
Periodic site inspections are needed to detect watershed violations, and a range of enforcement tools can be used to induce compliance correction notices, fines, stop-work orders, and even criminal penalties. In the case of OSTDS, compliance issues could include failure to install the system, improper installation or location, or failure to perform routine cleanouts or periodic rehabilitation.
Training and Education Outreach. Effective implementation of structural practices often requires a community investment in intensive training on how to design and apply watershed practices, since some consultants, engineers, and planners may be unfamiliar with current design practice.
For example, contractors and engineers may require training on new OSTDS testing or technology requirements, and outreach may also be needed for OSTDS owners to improve operation and maintenance.
Education and technical assistance are also critical in the implementation of nonstructural practices that involve private stewardship, pollution prevention, and land use management. Funding and Incentives.
The costs of applying and maintaining watershed practices can be significant for landowners or developers. This is particularly important for nonstructural protection strategies, such as conservation easements and other stewardship of private lands. Innovative financing systems such as stormwater or septic system "utilities" are often useful in providing long-term funding for the maintenance of structural watershed protection tools. Watershed Tracking. Over time, implementation results in the application of practices at hundreds of development sites, farms, properties, and other locations within a watershed.
In many cases, dozens of local, state, and federal agencies, utilities, land trusts, and watershed organizations are involved in various aspects of implementation.
Consequently, it is important to track the location, management status, and maintenance record of all practices to gauge the cumulative progress toward implementation in a coordinated fashion, namely with a multipurpose database that can be linked to a GIS.
Water quality monitoring is integral to measuring the success of any source water protection program. Monitoring data can be used to refine programs as necessary, by assessing the effectiveness of specific controls and identifying needed adjustments. In addition, monitoring is essential to earlier stages of watershed management, such as the watershed inventory and contaminant assessment steps.
This section broadly discusses the multiple purposes of monitoring for source water protection, including water quality monitoring, monitoring of health outcomes among the consumers of drinking water, and monitoring of social and economic parameters to determine the success of watershed management. Subsequent data analysis and program evaluation are highlighted because these are frequently the weakest steps in a watershed management strategy.
Monitoring for source water protection is implemented to address four general objectives: compliance with environmental regulations, systems operations, performance of BMPs, and modeling activities.
Compliance monitoring evaluates specific physical, chemical, and biological parameters for compliance with local, state, and federal regulations, including the SDWA. The methodologies used for monitoring most parameters are rigorously specified and regulated. An example of compliance monitoring might be daily sampling of turbidity, pathogens, and disinfection byproducts at the water intake. Operational monitoring is conducted on a broad set of parameters needed to effectively assess the ongoing and successional quality of water and reservoir dynamics and to determine the sources of pollution that influence water quality.
This type of sampling is typically conducted at a broad spatial scale e. Performance monitoring is needed to evaluate the effectiveness of watershed management practices and policies and to isolate design factors that influence the variability of pollutant removal. Performance monitoring often involves intensive sampling of flow and pollutant mass as it passes through a particular management practice such as a stormwater pond, OSTDS, or riparian buffer. Finally, monitoring data can be used to support modeling of projected changes in water quality under different conditions that are due to land use change or watershed management actions.
Modeling-support monitoring involves both intensive and extensive sampling of a reservoir and its watershed to define parameter values, set initial conditions, and physically characterize the watershed. These four types of monitoring are not mutually exclusive, and often data collected for one activity can be used in other contexts.
Physical, chemical, and biological parameters to target in monitoring for source water protection are described below. Viruses, bacteria, and protozoans originating from animal and human sources are often found in drinking water supplies prior to treatment, albeit at low concentrations. As noted in Chapter 3 , the protozoans Cryptosporidium and Giardia are especially troublesome because of their resistance to disinfection with chlorine.
Pathogen monitoring programs must be capable of measuring dilute concentrations of these organisms, determining their viability, and assessing the impact of treatment processes on their survivability in drinking water. As described in Chapter 3 , eutrophication refers to an increase in the rate of organic matter production in surface waters as a result of nutrient e. This increased organic matter can cause reductions in dissolved oxygen, alter taste and create odors in drinking water, and it can cause destruction of fish and aquatic plant habitat.
Comprehensive monitoring that encompasses a wide variety of eutrophication parameters including phosphorus, chlorophyll a , organic carbon compounds, and dissolved oxygen among others is critical to evaluating the success of source water protection programs. Natural organic compounds in a drinking water supply can react with disinfection agents e.
An effective monitoring program must be able to determine the sources and quantities of dissolved organic compounds and their potential for forming DBPs while taking into account seasonal variations and the operational flexibility of the water supply system. High turbidity levels are indicative of sediment transport generated by heavy or abnormal precipitation events in the drainage basins of source waters. Erosion either from land runoff or stream banks and the associated sediment transport can be detrimental to water supply systems and aquatic habitats for many reasons.
Turbidity has been shown to interfere with the disinfection process Symons and Hoff, In addition, sediments can introduce particulate-phase pollutants into water supply reservoirs.
Assessing and understanding these effects are important goals of an effective monitoring program. The presence of toxic chemicals in a drinking water supply is a more site-specific problem than the four pollutant categories discussed above. Those chemicals known to have adverse impacts on drinking water quality include metals and metalloids, synthetic organic chemicals, volatile organic chemicals, and pesticides.
Persistent bioaccumulating toxic chemicals, such as polychlorinated biphenyls PCBs and mercury, are particularly troublesome and are a potential concern for the long-term safety of water supplies.
Monitoring of toxic chemicals should take into account these site-specific considerations. In addition to monitoring water quality, a comprehensive watershed management strategy includes monitoring of public health to confirm that no waterborne disease outbreaks or unacceptable levels of endemic illness are associated with the water supply.
In some communities, this type of monitoring is mandatory for compliance purposes. There are several approaches for disease surveillance that can be implemented. Public health surveillance activities typically consist of reporting cases of specific infections to local and national public health agencies, such as county health departments or the Centers for Disease Control and Prevention CDC. Information on disease rates can serve several purposes as part of a watershed management program.
Its main role is to provide baseline data on disease trends over time in a target population. Baseline disease rates can then be compared with new information to determine whether specific disease rates are generally increasing or declining, to elucidate seasonal trends in specific disease rates, and to delineate high-risk populations or geographic areas.
Passive surveillance refers to the voluntary reporting of cases of ''notifiable" diseases to public health authorities by a health care provider or laboratory. The list of reportable diseases varies from state to state. Waterborne infections that are usually reported include salmonellosis, shigellosis, hepatitis A virus infection, typhoid fever, cholera, E. Passive surveillance systems are often very insensitive—especially for mild conditions where an ill person may not seek medical care—and thus they detect only a small fraction of the true incidence of cases.
Active surveillance is a system where the source of case information health care provider or laboratory is called on a regular basis to determine if any cases of a specific condition have been observed.
Although this process is considerably more sensitive than passive surveillance, the sensitivity of both active and passive disease surveillance is limited at multiple steps in the process. Finally, enhanced surveillance systems are those where "special additional efforts are made to encourage disease reporting" Frost et al.
Examples include surveillance for gastrointestinal disease in sentinel nursing homes, monitoring absenteeism in schools or among hospital employees, monitoring Health Maintenance Organization nurse hotline calls about gastrointestinal illness, and monitoring sales of antidiarrheal medications. These activities require far more intensity of effort and resources than passive surveillance but can provide real-time monitoring of the health of the target population.
Depending on the time for development of symptoms and on when a case is diagnosed relative to exposure, some active or enhanced surveillance systems may be able to alert health authorities about immediate, sharp increases in disease rates and enable detection of disease outbreaks.
However, in most instances, surveillance for disease is too slow to detect waterborne disease outbreaks. Surveillance systems collect information on illness rates in the community but cannot determine risk associated with drinking water because illness reported to state surveillance systems may be associated with contaminated food or other common transmission routes.
Determining whether an observed pattern of disease is associated with drinking water requires epidemiologic studies specifically designed to link health outcomes to specific exposures.
Most epidemiologic investigations of drinking water and health have been conducted following an outbreak of waterborne disease. Outbreak investigations have provided valuable information on risk factors and etiologic agents associated with waterborne disease. At least recognized waterborne outbreaks occurred in the United States between and , and enteric protozoa were the most frequently identified cause of waterborne outbreaks 20 percent and illnesses requiring hospitalization 78 percent Craun et al.
Epidemiologic studies are also designed to examine endemic baseline level waterborne disease or other health risks that may be associated with low levels of microbial or chemical contaminants in drinking water.
In situations where baseline levels of waterborne disease may be low, the study population must be large enough to detect any difference between the disease patterns in an "exposed" and an "unexposed" population.
Although most epidemiologic study designs are too expensive, time-consuming, and long-term to be conducted on a regular basis, a well designed and conducted study can provide the ultimate test of the safety of a water supply. Several epidemiologic study designs have been applied to the study of endemic waterborne disease Box Ecologic studies examine patterns of illness or infection collected from surveillance systems and concurrent data on water quality such as turbidity to determine if any correlation can be observed over space and time.
These descriptive studies are relatively inexpensive and easy to perform because they usually take advantage of existing data on health outcomes and water quality.
However, they are limited because they examine aggregate data from groups of populations and cannot take into account individual risk factors such as contact with child daycare centers or overseas travel or individual water exposure such as use of bottled water or length of residence in the study community.
In case-control studies, the exposure histories of individuals with the disease of interest "cases" are compared to the exposures of individuals without the disease "controls". Individual study subjects are queried about their residence history, water consumption habits, and risk factors for gastrointestinal disease. The analysis of these results allows the association between exposure and a single health outcome to be evaluated while controlling for individual risk factors.
Case-control studies cannot prove that exposure caused the adverse health outcome because they do not provide evidence that the exposure preceded the disease. However, they are useful for examining risk factors for specific health outcomes and require fewer participants than cohort studies described below.
Cohort studies also collect information on individual exposure, risk factors, and health outcomes. The illness rates in a group of people who are exposed to a water supply of interest are compared to the illness rates in a group of people exposed to a different water supply such as water receiving a different type of treatment, bottled water, or water receiving additional in-home treatment.
Because this design identifies the study population and measures exposure before the development of disease, it can be used to determine the temporal relationship between exposure and disease. These studies are typically the most expensive and time-consuming, especially if a long follow-up period is used. For all of these epidemiologic approaches, accurately measuring actual exposure to microbial pathogens or chemical contaminants in drinking water and choosing appropriate health outcomes from the wide array of possible water-associated health effects is extremely challenging.
Approaches and considerations for exposure assessment and outcome measurement are reviewed in detail elsewhere NRC, Although it is not explicitly addressed in most programs, monitoring of social and economic factors can play an important role in measuring the success of a watershed management strategy. The chosen parameters must be tailored to the goals of the specific watershed management plan. Social metrics of interest. A variety of ecologic studies have been conducted to demonstrate a correlation between health outcomes and water quality parameters.
Batik et al. However, no statistically significant associations were observed. A longitudinal study of French alpine villages that used untreated groundwater for their drinking water supplies observed a weak relationship between rates of acute gastrointestinal disease and the presence of fecal streptococci indicator bacteria in the public water system over a month study period Zmirou et al.
Illness data were collected through active surveillance by physicians, pharmacists, and schoolteachers, while weekly water samples collected from frequently used taps in the distribution system of each village were analyzed for several bacterial indicator organisms. Schwartz et al. However, a number of methodological problems with this investigation make the study results questionable. The role of filtration in affecting disease rates has been investigated in two contrasting studies. The first study examined Cryptosporidium antibodies in 86 blood samples collected from children as part of the lead-testing program in Massachusetts Griffiths, The authors concluded that there is significantly more exposure to Cryptosporidium for children supplied by an unprotected, filtered surface water than for children served by an unfiltered, protected supply and that increased watershed protection and more stringent filtration methods are need to reduce waterborne exposure to Cryptosporidium.
The second study evaluated cryptosporidiosis among AIDS patients in Los Angeles County by comparing prevalence in two communities with different types of water treatment Sorvillo et al.
One community used standard flocculation and sand filtration; the other community had. The water sources for both communities included surface waters from which oocysts had been recovered. From through , AIDS patients in both communities had a similar prevalence of cryptosporidiosis 6. During the 4-year period after filtration was installed in the second community — , cryptosporidiosis rates declined in both communities to 3. However, the authors noted that the ecologic nature of the study did not allow examination of the quantity and sources of water consumed by individuals, and there was no information on the levels of contamination in the different catchment areas for the two communities.
Two case-control studies have examined the relation between water supply and endemic giardiasis Chute et al. In these studies, cases of giardiasis were identified from a clinic or from a state registry, and controls individuals without giardiasis , matched for age and sex, were recruited from the same clinic, from acquaintances of the case, or by random digit dialing.
Cases and controls were either interviewed by telephone or they filled out a mail survey about potential risk factors such as source of drinking water, child daycare utilization, animal contacts, foreign travel, camping, and swimming in a natural body of fresh water. Both studies found that giardiasis was significantly associated with the use of a shallow dug well or surface water as the house-hold water source. Cohort studies in the form of randomized intervention trials were conducted in Canada to examine the risk of gastrointestinal illness associated with the consumption of conventionally treated municipal drinking.
The first study used households, of which were supplied with reverse-osmosis filters that provided additional in-home water treatment. Gastrointestinal symptoms were recorded in family health diaries. Water samples from the surface water source, treatment plant, distribution system, and study households were analyzed for several indicator bacteria and culturable viruses.
Over a month period, a 35 percent higher rate of gastrointestinal symptoms was observed in the study households drinking municipal tap water without in-home treatment compared to the study households supplied with reverse-osmosis filters. Symptomatology and serologic evidence suggested that much of this increased illness may be due to low levels of enteric viruses in the municipal water supply that originated from a river contaminated by human sewage.
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