Source water is untreated water from streams, rivers, lakes or underground aquifers that is used to provide public drinking water, as well as to supply private wells used for human consumption. Some water treatment is usually necessary, so public utilities treat most of the drinking water before it enters the home. However, the cost of this treatment, as well as the risks to public health, can be reduced by protecting source water from contamination.1 The idea of preventing contamination from entering the source water before it is treated is known as 'Source Water Protection'. The protection of our source water is not only important to maintain a clean supply for human consumption, but to ensure that our environment is healthy for all uses of water.

Key Advantages of SWP Include2:

  • Greater public health protection by ensuring higher quality raw water
  • Preventing contamination that treatment may not remove
  • Avoiding costs of contamination, including:
    • Reducing water treatment challenges and costs
    • Saving potential future costs associated with land and water contamination remediation
    • Saving monitoring, engineering, and legal expenses
    • Saving expenses related to finding and obtaining alternate water supplies
  • Greater likelihood of complying with existing and future drinking water regulations
  • Maintaining or improving source water quality for uses other than drinking
  • Protecting aesthetic water quality (prevention of taste, odor, and color problems
  • Meeting utility customer expectations, and improving or preventing a decline in customer/citizen perceptions and confidence
  • Providing for general environmental stewardship for current and future generations
  • Maintaining or improving utility bond ratings
  • Increasing funding opportunities
  • Increasing aesthetic beauty and/or economic value of residential and commercial properties through use of best management practices (BMPs) (e.g. artificial ponds or wetlands)
  • Improving communication and cooperation among stakeholders
  • Improving operations and reducing expenses for various industries and commercial establishments (e.g. nutrient management plans may reduce the need for fertilizer; sediment control BMPs can maintain soil resources)

Components of Source Water Protection

The six primary components of successful SWP programs and the requirements for meeting the standard are outlined below2:

  • 1. VISION - A formalized vision guides the development and implementation of a SWP program. The vision may be articulated in a mission statement or policy of the governing body of the utility and is a statement of the utility's commitment to SWP.

  • 2. SOURCE WATER CHARACTERIZATION - In essence, this is the information collection and analysis phase of SWP programs. Characterization and assessment of the source water and the land or sub-surface area from which the source water is derived is essential for obtaining the understanding and knowledge needed to develop the goals and plans that will realize the SWP vision.

  • 3. PROGRAM GOALS - Goals and objectives need to be formulated to guide the SWP program and its specific elements. The goals should be targets developed in response to specific problem areas identified through the source water and SWP area characterization and risk assessment processes. They should address each of the drivers motivating the SWP program, including the SWP vision.

    Goals may address both current and potential future issues. The goals should be prioritized to reflect the concerns of greatest importance and ideally should specify temporal and qualitative and/or quantitative dimensions (e.g., specific timelines and measurable goals). Both internal and external stakeholders should be involved in the development of goals.

  • 4. ACTION PLAN - The action plan lays out a road map of activities to be conducted to achieve the desired watershed protection goals based on the vision, source water area characterization, and susceptibility analysis. The plan identifies required actions (regulations, agreements, practices, etc.) to mitigate existing and future threats to source water quality. It develops priorities and a timetable for implementation and identification of necessary resources, and a means for obtaining those resources (e.g. funding). These priorities may be based on the perceived risk from different contaminant sources, the available resources to implement actions, the likelihood of success of different actions, and the obstacles to success that exist for different contaminant sources and action plans.

  • 5. IMPLEMENTATION - Implementation of the action plan is the core of any SWP program. Planning without implementation does not provide results, and without this step no actual protection takes place. The development of a comprehensive and implementable pla, the use of an adaptive and iterative management approach to respond to unexpected challenges and barriers, and adherence to an established timeline are all integral to the success of implementing a SWP program.

  • 6. EVALUATION & REVISION - Administrative programs of any type require periodic (or continuous) evaluation and revision. A good SWP program will include provisions for reviewing and, if necessary, modifying the utility's SWP vision, characterization, goals, action plan, and implementation elements. This should be done on a periodic basis and also in response to changes in the source water area, changes in contaminant sources, performance of implemented programs, and so forth. This step is intended to measure the accomplishment or completion of projects, programs, and activities identified in the action plan, and to identify any obstacles preventing further success.

1 EPA's Source Water Protection Website
2 Modified from AWWA, Source Water Protection, Operational Guide to AWWA Standard G300

Image Credit: WATER.EPA.GOV

A Source Water Protection IQ Test is presented here in order to help you review the concepts of the various core components of source water protection.

In this test, clicking on a choice will automatically enter the number of points for that option and keep track of the score for each section of the Source Water Protection IQ as well as the total cumulative score. If a new answer is selected, the new choice and the new points will appear and the old points will be removed.

The Source Water Protection IQ Test will take you from considerations of your vision for source water protection to characterization of areas of concern and evaluation of the data available. It then guides you to consider your goals for source water protection and evaluates your action plan for implementing your goals. Finally, it asks you to consider stakeholder input and your process for continued evaluation and review of your plan. Taking the test in this order before starting a source water protection plan should help you in considering the steps needed to initiate and fully implement a plan.

As the utility progresses, the Source Water Protection IQ can be repeated and the scores compared to previous scores. Repeating it periodically can point out gaps in your information or weaknesses in your process and help you to focus your efforts efficiently. At a minimum, you may wish to repeat the test every year.

Start the Source Water IQ HERE

Source Water Protection Resources

Planning Tools

A wide variety of technical and managerial source water protection practices are available for use, including management practices for point and nonpoint pollution sources; stormwater management; wastewater treatment plant upgrades and maintenance; rules and assistance for maintaining septic systems; agricultural management practices, incentives, and land stewardship programs; erosion and sediment control for construction projects; land-use controls; source water monitoring (including early warning monitoring and chemical and microbial pollutant source tracking); and watershed protection, management, and stewardship programs.

In order for a water utility to implement source water protection practices they must have a plan in place. The following two planning tools will help guide a utility in their decision making processes.

Source Water Assessment


The objective of a source water assessment is to identify point-sources and non-point-sources of potential contamination to drinking water source(s). For example, a point-source may be a business' discharge pipe or a septic system. Examples of non-point-sources may be chemically treated agricultural land or disturbed land on a construction site.

  • Ultimately, the source water assessment will steer recommendations in the source water/wellhead protection plan, discussed below.
  • Your system may already have an initial source water assessment that your state, tribal, and/or federal regulatory authority developed.
Elements to include in a source water assessment
  • Identification and map(s) of the area(s) that influence the water source(s); these are the source water protection areas; resources may include previous studies, Geographic Information System (GIS) data, hydrologic studies of the area, hydrologists, zoning maps, aerial photography, satellite imagery, topographic maps, soil maps, geologic maps.
  • Inventory of documented and potential contamination sources within the protection area: current and future commercial, industrial, residential, waste management, and development activities, agriculture, etc. that may be potential threats to drinking water supplies.
  • Analysis of likelihood that contamination could occur: determine if there are already zoning or best management practices in place to protect wells, waterways, floodplains, wetlands, etc. from livestock, erosion, runoff, etc.
  • Analysis of contamination impact severity
  • Prioritization of contamination threats and vulnerabilities based on analysis.

Review and revision

A source water assessment addendum must be provided for each new water source added to the system.

Source Water/Wellhead Protection Plan


Virtually every stream, lake, river and aquifer in the United States is used as (or is connected to) a drinking water source. Protecting these source waters from contaminants is a major national priority in protecting public health through ensuring a clean, safe drinking water supply. The source water protection plan will respond to the priorities identified in the source water assessment (see above).


Writing the plan will normally require a project team including representatives from not only the water system, but also agricultural/commercial/industrial/development businesses, any local/state/federal/tribal entities with authority to make regulatory or land use decisions in the source water protection areas, other water providers, conservation/environmental/watershed groups, teachers, and citizens.

Elements to include in a source water assessment
  • You may wish to document public and stakeholder involvement and who was on the project team in your written plan.
  • Using the threat/vulnerability prioritization in the source water assessment (see above), the team will identify ways to minimize or eliminate each threat/vulnerability or group of similar threats.
  • From source to tap, there are numerous points to capture and safeguard clean water or treat contaminated water.
    • The source: the lakes, rivers, streams, reservoirs, and aquifers (groundwater sources) that provide drinking water
    • Treatment, through filtration and disinfection, is the next barrier against contaminated water
    • The final barrier is infrastructure.
  • Regulatory tools such as zoning & permits, health regulations, and performance standards may be used to protect water sources. If a water system is in an unincorporated area where no zoning or subdivision regulation can be applied, the water system still has a variety of tools it can employ to protect its water source(s). Non-regulatory management tools include public education, citizen involvement, best management practices (BMPs are often applicable to agricultural land), land or conservation easement acquisition and protection (such as fences), and water conservation (to minimize the intrusion of contaminants or saltwater into groundwater, which can happen when they migrate into the space where groundwater used to be).
Elements to include in a source water or wellhead protection plan
  • Source water assessment: protection area(s) delineation, potential contaminants and threats inventory, analyses, prioritization (see above).
  • Management measures to prevent, reduce, or eliminate threats:
    • Using the information gathered and analyzed in the assessment allows management measures to be formulated and put in place that address each threat or array of risks specific to your system
    • The use of both non-regulatory and regulatory management practices is encouraged.
  • Public education
    • Notify and involve the public about threats identified in the contaminant source inventory and how they affect the water system
    • Ensure that the public has information necessary to control and modify their own actions to prevent contamination and to participate effectively in community activities to protect drinking water.
  • Monitoring: Test for water quality, ensure that management measures are properly implemented, followed, and maintained, etc.
  • Contingency planning: this item will be completed the same way as for an emergency water supply plan; refer to your emergency water supply plan if it is a stand-alone document or incorporated into your emergency response plan.
Review & revision

A source water protection plan addendum must be provided for each new water source added to the system. Otherwise, source water protection plans and implementation should be reviewed annually, but no less than once every five years.

Selected Resources

Operational Guide to AWWA Standard G300, Source Water Protection, Second Edition
Download HERE

Hopper, Kim, and Ernst, Caryn. Source Protection Handbook - Using Land Conservation to Protect Drinking Water Supplies. The Trust for Public Land and the American Water Works Association, 2005.
Download HERE

United States Environmental Protection Agency. Consider the Source: A Pocket Guide to Protecting Your Drinking Water. Office of Ground Water and Drinking Water, June 2002.
Download HERE

Elements to include in a source water or wellhead protection plan
  • Protecting Your Drinking Water Through Wellhead Protection - A "How To" Workbook For Small Water Systems. Undated. Download HERE
  • Protecting Your Watershed Through A Source Water Assessment and Protection Plan - A "How To" Workbook for Communities and Watershed Groups.
  • Wellhead Protection Workbook. January 1993. Downlaod HERE
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