The City of Oceanside (City), as defined in the California Water Code section 10617, qualifies as an “Urban Water Supplier”. The City is a public agency directly providing water for municipal purposes to more than 3,000 customers. As such, the City is required to complete an Urban Water Management Plan (UWMP) every five years. This report constitutes the 2015 Urban Water Management Plan (2015 Plan) which must be adopted by the Oceanside City Council and submitted to DWR by July 1, 2016. This 2015 Plan satisfies the requirements of the CWC, the Act, and subsequent amendments. In addition to satisfying regulatory requirements, this report is a resource document that includes an analysis of long-term water supply and demand planning for the City’s service area.