Watershed Management for Potable Water Supply Assessing the New York City Strategy (2000) / Chapter Skim
Currently Skimming:
4 Watershed Management For Source Water Protection
4 Watershed Management For Source Water Protection
Pages 130-157
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 130... ...
. Source water protection programs are essentially watershed management programs with the specific goal of protecting drinking water supplies.
|
From page 131... ...
. Figure 4-1 depicts the components of a watershed management framework for source water protection advocated by the committee.
|
From page 132... ...
The watershed management process is dynamic and iterative, and the steps in Figure 4-1 are repeated as conditions within the watershed evolve and new information becomes available. It should be kept in mind that this chapter describes an ideal water management strategy that might be used for source water protection.
|
From page 134... ...
Beyond this general goal, specific goals can be tailored to a watershed's physical characteristics, existing water quality concerns, contaminant sources, and regulatory constraints (AWWARF, 1991~. Detailed numeric objectives often complement general goals by providing quantifiable and measurable direction for source water protection programs.
|
From page 135... ...
One example of a goal is "to protect the water quality and supply reliability by seeking to balance the watershed uses such as the rights of private property owners and public recreational activities with the protection and management of natural resources" (Santa Clara Valley Water District, 1995~. The Santa Clara Valley Water District goal recognizes the need for public support and for cooperation from other stakeholders to ensure a successful source water protection program.
|
From page 136... ...
WATERSHED INVENTORY AND CONTAMINANT ASSESSMENT An inventory of the watershed and an assessment of potential contaminants help to define the boundary conditions and form the basis for source water protection programs. A watershed inventory begins with a delineation of the source water protection area and an evaluation of existing water quality conditions.
|
From page 137... ...
can serve as readily available summaries of water quality conditions relative to use classifications and water quality criteria. For source water protection, some constituents are of particular concern because of their potential impact on water supply treatment and finished water quality.
|
From page 138... ...
Recreational activities, both within watersheds and on bodies of water, can also affect water quality. Contaminant Assessment Existing and potential contaminant sources identified during the watershed inventory should be assessed for their future impact on source water quality.
|
From page 139... ...
It has been widely applied in source water protection and watershed planning initiatives across the nation (EPA, 1996~. A GIS can be built to house multiple "layers" of information to support a watershed inventory.
|
From page 140... ...
DEVELOPMENT OF PROTECTION STRATEGIES Comprehensive source water protection includes multiple structural and nonstructural protection strategies to remove or reduce contaminant sources of surface and groundwater supplies. Effective protection strategies focus on highpriority watershed activities and contaminants and target the ones with the greatest potential to affect water sources.
|
From page 141... ...
and in Chapters 8-11. Nonstructural Practices Nonstructural controls prevent or reduce potential pollution discharges from future sources.
|
From page 142... ...
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.
|
From page 143... ...
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.
|
From page 144... ...
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.
|
From page 145... ...
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.
|
From page 146... ...
Monitoring of Public Health 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.
|
From page 147... ...
Epidemiological Studies of Waterborne Disease 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.
|
From page 148... ...
Approaches and considerations for exposure assessment and outcome measurement are reviewed in detail elsewhere (NRC, 1998~. Monitoring of Social and Economic Parameters 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.
|
From page 152... ...
Depending on the scope of the watershed management program, such factors as these are likely to change during program implementation and merit monitoring because of their importance to overall program success. Evaluation of Monitoring Data and Information Monitoring, by itself, has limited management value in source water protection efforts unless it is integrated within a larger framework of watershed evaluation.
|
From page 153... ...
Trends in the risk estimate over time can be used to evaluate the watershed management program over time. These and other types of evaluations of monitoring data are suggested throughout this report.
|
From page 154... ...
For this reason, expanding environmental awareness and improving stakeholder education are critical to the success of a watershed management program. Education may broadly be thought of to include not only formal school curricula, but also media coverage and government dissemination of information.
|
From page 155... ...
CONCLUSION This chapter has defined the elements of a watershed management strategy for source water protection. As is apparent in Figure 4-1, watershed management is iterative or cyclical, designed to respond to natural, legal, social, political, and economic changes.
|
From page 156... ...
1997. Source Water Protection Statement of Principles.
|
From page 157... ...
1998. Salt Lake City Watershed Management Plan.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.