Water System Planning Requirements

Water System Planning Guidebook
Our Water System Planning Guidebook 331-068 (PDF) is ready for your use. The Guidebook's purpose is to help water system governing bodies, managers, and operators understand their role in water system planning, and work with their consultants and constituents to prepare a useful water system plan. At more than 100 pages, it covers key technical, managerial, and financial elements important to crafting a good plan and overall water system management. These key elements range from asset and financial management to source water protection, and the guidebook provides many tips to support all parties involved develop a quality plan.

Water System Plans

Planning is the foundation of a safe, successful, and sustainable public water system. The categories of community systems identified below are required to submit a Water System Plan (WSP) for review and approval.

A Group A community water system must submit a WSP or a Plan update under WAC 246-290-100 if it meets any of the following conditions.

  • Serves 1,000 or more connections, or
  • Is a new Group A water system, or
  • Proposes to do any of the following:
    • Make infrastructure changes to increase the approved number of connections.
    • Expand the service area identified in a previously approved planning document or engineering project.
    • Expand the geographical area where direct service is already provided if a planning or engineering document has not been previously approved.
  • Seeks to be eligible for the "document submittal exception" process, or
  • Is directed to submit a WSP because of demonstrated operational, managerial, or financial problems, or
  • Is municipally owned or located in a critical water supply area. If your system falls into this category, but it is not expanding, contact your regional planner about the appropriate planning document, or
  • Seeks to be eligible for Drinking Water State Revolving Fund (DWSRF) resources and does not have a current WSP that addresses the proposed project.

More information is available on the Rulemaking webpage.

Small Water System Management Program

All community and noncommunity water systems not required to submit a WSP must develop and implement a Small Water System Management Program (SWSMP) under WAC 246-290-105.

Visit our Small Water System Management Program webpage for information on when a SWSMP is required, and for guidance on how to develop a SWSMP for a community or a non-community system.

Preplan Meeting

If your system is required to submit a WSP, WSP update, or a SWSMP, the first step is to contact your Office of Drinking Water regional planner and set up a preplan meeting. We strongly encourage all water systems to meet with our regional engineering and planning staff before developing a planning document that will be submitted for our approval.

A preplan meeting will help you determine the appropriate level of information to include in your plan. You can also find out if you will need to submit additional information in order to meet financial viability requirements for DWSRF applications. There is no charge for this meeting.

Related Resources

Office of Drinking Water

Systems interested in applying for DWSRF grants or loans should visit the Drinking Water State Revolving Fund webpage.


Eastern Region Spokane Valley 509-329-2100

Northwest Region Kent 253-395-6750

Southwest Region Tumwater 360-236-3030