In fact, water-shed protection is the primary barrier, the first line of defense against contamination of drinking water at its source.. Land use and activities in the watershed directly
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Watershed protection is one of the barriers in the multiple barrier approach to protecting source water In fact, water-shed protection is the primary barrier, the first line of defense against contamination of drinking water at its source Ideally, under the general concept of “quality in, means quality out,” a protected watershed ensures that surface runoff and inflow to the source waters occur within
a pristine environment.
Protecting watersheds is not only critical to humans in
ensuring their continued growth in numbers but is critical
to their very survival Simply put, protecting watersheds is
a challenge that we must meet While it is true that
envi-ronmental protection programs in the U.S have gone a
long way toward improving water quality during the last
quarter century, yet, many challenges remain According
to U.S Environmental Protection Agency (EPA), as of
1994, nearly 40 percent of surveyed waters in the U.S
remain too polluted for fishing, swimming and other uses
The leading causes of impairment found in the survey
include silt, sewage, disease-causing bacteria, fertilizer,
toxic metals, oil and grease.*
16.1 INTRODUCTION
Water regulates population growth, influences world
health and living conditions, and determines biodiversity
For thousands of years, people have tried to control the
flow and quality of water Water provided resources and
a means of transportation for development in some areas
Even today, the presence or absence of water is critical in
determining how we can use land
Yet, despite this long experience in water use and water management, humans often fail to manage water
well Sound water management was pushed aside in rapid,
never-ending economic development in many countries
Often, optimism about the applications of technology
(e.g., dam building, wastewater treatment, or irrigation
measures) exceeded concerns for, or even interest in,
envi-ronmental shortcomings Pollution was viewed as the
inevitable consequence of development — the price that
must be paid to achieve economic progress
Clearly, we now have reached the stage of our devel-opment when the need for management of water systems
is apparent, beneficial, and absolutely imperative Land
use and activities in the watershed directly impact raw water quality Effective watershed management improves raw water quality, controls treatment costs, and provides additional health safeguards Depending on goals, water-shed management can be simple or complex
This chapter discusses the need for watershed man-agement based on a multiple barrier basis and provides a brief overview of the range of techniques and approaches that can be used to investigate the biophysical, social, and economic forces affecting water and its use
Water utility directors are charged with providing potable water in a quantity and quality to meet the public’s demand They are also charged with providing effective management on a holistic basis of the entire water supply system; such management responsibility includes proper management of the area’s watershed
Key Point: Integrated water management means putting all of the pieces together, including considering social, environmental, and technical aspects
16.2 CURRENT ISSUES IN WATER MANAGEMENT
Note: Much of the information provided in this sec-tion is adapted from Viessman, W., Jr., Water management issues for the nineties, Water Resources Bulletin,26, 883–981, 1991
Remarkable consensus exists among worldwide experts over the current issues confronted by waterworks manag-ers and othmanag-ers These issues include the following:
1 Water availability, requirements, and use
a Protection of aquatic and wetland habitat management of extreme events (droughts, floods, etc.)
b Excessive extractions from surface and groundwater
c Global climate change
d Safe drinking water supply
e Waterborne commerce
2 Water quality
a Coastal and ocean water quality
b Lake and reservoir protection and restoration
c Water quality protection, including effective enforcement of legislation
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d Management of point- and nonpoint-source
pollution
e Impacts on land/water/air relationships
f Health risks
3 Water management and institutions
a Coordination and consistency
b Capturing a regional perspective
c Respective roles of federal and
state/provin-cial agencies
d Respective roles of projects and programs
e Economic development philosophy that
should guide planning
f Financing and cost sharing
g Information and education
h Appropriate levels of regulation and
dereg-ulation
i Water rights and permits
j Infrastructure
k Population growth
l Water resources planning, including:
i Consideration of the watershed as an
integrated system
ii Planning as a foundation for, not a
reac-tion to, decision making
iii Establishment of dynamic planning
pro-cesses incorporating periodic review
and redirection
iv Sustainability of projects beyond
con-struction and early operation
v A more interactive interface between
planners and the public
vi Identification of sources of conflict as
an integral part of planning
vii Fairness, equity, and reciprocity between
affected parties
16.3 WHAT IS A WATERSHED?
At the simplest level, we all live in a watershed — the
area that drains to a common waterway, such as a lake,
estuary, wetland, river, stream, or even an ocean — and
our individual actions can directly affect it More
specif-ically, a watershed is a protected, reserved area, usually
distant from the treatment plant, where natural or artificial
lakes are used for water storage, natural sedimentation,
and seasonal pretreatment, with or without disinfection
A watershed is also defined as a collecting area into which
water drains The area of land encompassed could be tiny
or immense The size of a watershed, and the direction of
flow of its rivers, is determined by landforms Watersheds
are associated with surface water (usually fed by gravity)
to distinguish them from groundwater (usually fed by
pumping)
Note: EPA’s watershed approach is to provide for an
“integrated, holistic strategy for more effectively restoring and protecting aquatic ecosystems and protecting human health (e.g., drinking water supplies and fish consumption).” (U.S EPA, Committing EPA’s Water Program to Advancing the Watershed Approach, http://www.epa.gov/ owow/watershed/memo.html Accessed Decem-ber 2002.)
16.4 WATER QUALITY IMPACT
Generally, for a typical river system water quality is impacted by about 60% nonpoint pollution, 21% munic-ipal discharge, 18% industrial discharge, and about 1% sewer overflows Of the nonpoint pollution, about 67% is from agriculture, 18% is from urban, and 15% is from other sources
Land use directly impacts water quality The impact of land use on water quality is clearly evident in Table 16.1 From the waterworks operator point of view, water quality issues for nutrient contamination can be summa-rized quite simply:
1 Nutrients + Algae = Taste and Odor Problems
2 Nutrients + Algae + Macrophytes + Decay = Trihalomethane Precursors
16.5 WATERSHED PROTECTION AND REGULATIONS
The Clean Water Act and Safe Drinking Water Act Reauthor-ization addresses source water protection Implementation
of regulatory compliance requirements (with guidance pro-vided by the U.S Department of Health) is left up to state and local health department officials to implement Water protection regulations in force today not only provide guidance and regulation for watershed protection, but they also provide additional benefits for those tasked with managing drinking water utilities
The typical drinking water utility (which provides safe drinking water to the consumer) has two choices in water pollution control: “Keep it out or take it out.” The “keep
it out” part pertains to watershed management; if the water supply contains contaminants, they must be removed by treatment, “take it out.” Utility directors and waterworks managers are concerned with controlling treatment costs
An effective watershed management program can reduce treatment costs by reducing source water contamination The “take it out” option is much more expensive and time consuming than keeping it out in the first place
Proper watershed management also works to maintain consumer confidence If the consumer is aware that the water source from the area’s watershed is of the highest quality, then logically, confidence in the quality of the
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water is high High-quality water also works directly to
reduce public health risks
16.6 A WATERSHED PROTECTION PLAN
Watershed protection begins with planning The watershed
protection plan consists of several elements and includes
the need to:
1 Inventory and characterize water sources
2 Identify pollutant sources
3 Assess vulnerability of intake
4 Establish program goals
5 Develop protection strategies
6 Implement program
7 Monitor and evaluate program effectiveness
16.7 RESERVOIR MANAGEMENT
PRACTICES
To ensure an adequate and safe supply of drinking water
for a municipality, watershed management includes proper
reservoir management practices These practices include
proper lake aeration, harvesting, dredging, and use of
algi-cide Water quality improvements from lake aeration
include reduced iron, manganese, phosphorus, ammonia,
and sulfide content Lake aeration also reduces cost of
capital and operation for water supply treatment Algicide
treatment controls algae, which in turn reduces taste and
odor problems The drawback of using algicides is that
they are successful for only a brief period
16.8 WATERSHED MANAGEMENT
PRACTICES
Watershed management practices include land
acquisi-tions, land use controls, and best management practices
(BMPs) Land acquisition refers to the purchase of
water-shed lands — those land areas that form the waterwater-shed for
a particular locality The advantage of ownership of lands
included within a particular watershed are obvious; the
owner (in this case, the local utility) has better control of land use, and thus can effect protective measures for ensur-ing a quality water supply
Land use controls (those measures deemed necessary
to protect the watershed from contamination and/or destruction) vary from location to location For example, land use controls may be designed to prohibit mining or other industrial activities from taking place within the watershed, for protection of the water supply
BMPs for watershed management refer specifically to agriculture, logging, urban, and construction practices The chief problem with best management practices is that they are nonstructural measures They are often hard to implement because they require people to change the way they behave
In agricultural systems, BMPs may include measures such as conservation tillage and contour plowing, confined animal facility management (contain or use waste on-site and keep animals out of waterways), and appropriate pes-ticide and herbicide application practices (minimize use
or use alternative chemicals)
Examples of logging BMPs include construction of streamside buffer zones to protect the watercourse Log-ging plans should also incorporate water quality and hab-itat planning
Urban BMPs revolve around targeted categories such
as reduction of impervious areas (reducing tarmac, asphalt covering, and cement covering to allow for precipitation infiltration), nonstormwater discharges, and proper dis-posal of residential chemicals
The primary types of BMPs used include public edu-cation programs, inspections and enforcement, structural controls (end-of-pipe solutions that seek to treat or remove pollution that has already occurred) and preventive options that are implemented to prevent or reduce the creation of waste within a process
Examples of construction BMPs include enforcement
of stormwater pollution plans and inspections Types of construction BMPs include erosion and sediment control (i.e., minimize clearing, stage construction, and stabilize stockpiles and finished areas) and chemical control (i.e.,
TABLE 16.1 Land Use Directly Impacts Water Quality
Lan-caster, PA, 2001.
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proper storage, handling, application and covering, and
isolation of materials)
16.9 CHAPTER REVIEW QUESTIONS
AND PROBLEMS
16.1 Define watershed
16.2 Another name for watershed is
16.3 Explain “keep it out” and “take it out.”
16.4 What is the purpose of algicide in reservoir management?
16.5 Does the acronym BMP mean?
REFERENCE
1 U.S Environmental Protection Agency, Watersheds,
http://epa.gov/owow/watershed/framework/ch1.html, Washington, D.C., accessed on Nov 2, 2002.