Lake County staff outline limited water portfolio, phased augmentation program and Aurora IGA timeline

Lake County water resources program manager Bryce Ehrlich briefed the Planning Commission on Oct. 1 on the county's Water Enterprise, describing the county's limited water supply, the new water-marketing policy (Resolution 24-39) and near-term steps to operationalize augmentation for domestic use.

The presentation matters because Lake County's portfolio is small and newly usable statewide only under a court decree; how the county allocates that water will determine whether owners can add accessory dwelling units (ADUs), drill residential wells or seek small commercial water approvals. "I am the county's staff member that handles water resources full time," Ehrlich said, noting the program is designed to be administratively self-sustaining.

Ehrlich summarized the county's supply and limits: the county holds a firm, trans-basin allocation from the City of Aurora of 40 acre-feet per year and an average yield of roughly 34 acre-feet per year from Dairy Ditch No. 3, for a near-term working total of about 74 acre-feet. He emphasized those volumes are small: "Hayden Pond is roughly 50 acre-feet of storage," he said, and the combined flow equals only about one and a half Hidden Ponds.

Under the Water Marketing Policy (Resolution 24-39) the county will make augmentation units (AUs) available to specified uses only. An augmentation unit equals 0.1 acre-foot and is intended to match an Equivalent Residential Quantity (EQR) defined in…