Reports & Plans

The Water Policy and Resources Development Department is responsible for developing viable plans and initiatives to ensure reliability of the region's water supplies. It plays an important role in reducing the region's dependence on imported water by expanding the local water supply portfolio in an economically feasible manner. Through effective partnerships and innovative planning, the staff continues to demonstrate a proactive approach to water resource management.

West Basin develops three planning documents: The Annual Water Use Report, Urban Water Management Plan and The Drought Rationing Plan.

Water Use Report

Every year West Basin develops the Water Use Report to inform its customer agencies, Board of Directors and key stakeholders of the service area's annual water usage as well as its customer agency's retail usage. It is designed to be a water resource reference tool summarizing the following information:

  • 10-year historical water use (imported, recycled, and groundwater)
  • Water use by month over the most recent fiscal year
  • Tier 1 and commitment amount
  • Potable meter connection data
  • Imported & recycled water rates & charges
  • Contact information
  • Recycled water connections

In addition, the report briefly highlights some of the recent activities West Basin is engaged in within the service area.

Download the PDF version

Archived Reports

Urban Water Management Plan

The State of California, through the California Water Management Planning Act of 1983, as amended, requires every urban water supplier to develop an Urban Water Management Plan (UWMP) every five years to demonstrate in detail how their agency manages their water supplies and demands under all hydrology conditions. Following the public hearing held on June 27, 2016, the West Basin Board of Directors adopted the UWMP.

This plan demonstrates not only how West Basin plans to meet its service area's retail demands over the next 25 years, but also how they plan to provide long-term water reliability through supply diversification. Since West Basin's formation in 1947, West Basin has strived to ensure water reliability. Through its efforts in recycled water, conservation, education, groundwater recovery and ocean water desalination research, West Basin continues to be a leader in water reliability by investing in a well-balanced water supply portfolio.

Download the 2015 Urban Water Management Plan

Drought Rationing Plan

The West Basin Drought Rationing Plan (DRP) was in effect from 2009-2011 (under the name Water Shortage Allocation Plan) and 2014-2015.The information below describes the methodology used to implement the DRP.

Metropolitan Water District’s (MWD) Board of Directors approved the amended Water Supply Allocation Plan in March, 2015 under the new name Drought Rationing Plan. It is based on a guiding principle developed almost 15 years prior as part of their Water Surplus and Drought Management Plan.

“Metropolitan will encourage storage of water during periods of surplus and work jointly with its member agencies to minimize the impacts of water shortages on the region’s retail consumers and economy during periods of shortage.”

Fairness in allocation and minimizing regional hardship to retail water consumers remained central themes in the development of a specific formula for allocating shortages across Southern California. The formula uses different adjustments and credits to balance impacts of shortage at the retail level, where local supplies can vary dramatically, and provide equity on the wholesale level among member agencies. It also attempts to take into account; growth in demand, local investments, changes in local supply conditions, the reduction in potable water demand from recycled water, and the implementation of water conservation programs.

Based closely on MWD's methodology, West Basin’s Drought Rationing Plan model, adopted by the Board of Directors in April 2009 and amended in March 2015, determines each customer agency’s share of West Basin’s allocation from Metropolitan.