Lake County, Aurora negotiate IGA renewal as Box Creek, storage and local water rights loom

Lake County water staff and officials from the City of Aurora spent a work session outlining terms being negotiated in a renewed intergovernmental agreement that would formalize delivery of 40 acre‑feet of Aurora water to Lake County each year and clarify how the county may use storage and augmentation to operate a new county water enterprise.

The discussion, led by Water Resource Manager Bryce Erlich and Rick Kinitz, basin manager for Aurora, focused on three linked items: the IGA renewal, near‑term storage options including using Hayden Meadows Recreational Pond, and the long‑range possibility of participating in the Box Creek Reservoir project. "Acre feet is kind of the standard unit we use in water supply. It's 326,000 gallons roughly," Erlich told the board while explaining units and augmentation concepts used in the county's plan.

The IGA under negotiation would preserve an annual delivery obligation from Aurora of 40 acre‑feet — described in the meeting as a firm delivery Aurora owes Lake County under the parties' existing arrangements — and would add flexibility on where Aurora may release that water on the county's behalf. "Aurora has an obligation to release that much water to you, 40 acre feet every year," Kinitz told the commissioners. Staff said the agreement also aims to put current delivery practices — where Aurora has sometimes released the water in increments throughout the year — into a written right that Lake County can rely on for its augmentation accounting.

Why it matters: Lake County's 1998 change case and blanket augmentation decree (filed as 98CW173 and finally adjudicated in 2017) provides the legal basis for the county's augmentation plan and for using consumptive credits; the Aurora IGA supplies an additional, externally controlled bucket of water that county staff say is critical to operate the county water enterprise and to support development and permitted uses in the county.

Storage and operational details were a primary focus. County staff and Aurora officials discussed a proposal under which Aurora would continue delivering 40 acre‑feet annually and Lake County could use its existing Hayden Meadows Recreational Pond for short‑term storage if the parties agree on a backfill arrangement. Erlich and Kinitz described a draft mechanism in which Lake County could release water from Hayden Meadows for augmentation duties and Aurora would backfill the pond so that surface levels for recreation and fisheries would not fluctuate substantially. Erlich said Hayden Meadows holds roughly 49 acre‑feet of storage and the county currently accounts for about 17 acre‑feet per year of evaporative loss tied to the pond; staff said the IGA negotiations include language on sharing evaporative losses when storage is used jointly.

Longer‑term planning is tied to Box Creek Reservoir, a large proposed storage project Aurora is advancing. City officials said the current conceptual design is about 23,000 acre‑feet and that Lake County would receive 20 percent of storage space in addition to the 40 acre‑feet annual delivery. Kinitz cautioned the project is many years away and subject to permitting and geological study; staff repeatedly called the Box Creek timeline "long term" and said Aurora and the county currently expect any large storage project would likely be post‑2050. Kinitz and Erlich also described opportunities to coordinate outlet works and pipeline work so Box Creek could provide mutual operational benefits to Aurora (for its transmountain deliveries) and Lake County (for local augmentation and storage).

Participants identified operational and legal constraints. Erlich reviewed Colorado water law basics for the board and emphasized that the state controls water rights administration; the county's decree grants it a mix of consumptive credits equating to roughly 73–74 acre‑feet a year when averaged, of which 40 acre‑feet come through the Aurora arrangement and the remainder derives from county rights such as Dairy Ditch No. 3 and Mount Albert diversions. Staff stressed that augmentation allows the county to ‘‘use out of priority’’ by replacing consumptive uses on the river system in other seasons, but also that any water transfers, storage or delivery mechanisms must match court decrees and reclamation or state permitting requirements.

County commissioners and residents pressed on near‑term risks and local impacts. Several speakers raised concerns about wells that have failed or experienced lower yields near Twin Lakes and Mount Albert, where increased measured use and new substitute water supply plans (SWSPs) and water court applications have changed local hydrology. Paul Terranova, introduced as general manager of a local water association, described recent metering and the constraints of existing certificates and supply in his association, noting growth will be gradual and that augmentation protections matter to residents. Erlich and Aurora staff said they are monitoring substitute water supply plans, leases, and new water court filings and that Lake County's legal and engineering teams are reviewing applications to protect the county's senior rights and augmentation area.

Permitting and other non‑water issues also surfaced: Kinitz said Box Creek would require a county 1041 process and multiple other permits, and Aurora staff described land swaps and negotiations with the State Land Board over parcels that intersect the proposed reservoir footprint. Officials also addressed remediation and mining legacy issues at potential reservoir sites, noting state land‑board priorities for revenue and that some historic structures in the footprint have documentation but likely would not be preserved in situ.

Next steps and staff direction: County staff indicated the IGA text is largely negotiated at the staff level and is now under lawyer review to clarify legal language and finalize obligations. No formal board vote occurred during the session; staff asked the board for confirmation of policy directions and said they expect to return with a final draft after attorney review. Erlich said a separate work session will review the county's water marketing policy and additional mechanics of how the enterprise will operate.

The presentation and discussion lasted the scheduled work session and were recorded for later review; staff encouraged commissioners and interested residents to view the recording and the slides when the county posts them.

Ending note: Officials characterized the IGA renewal as an important step to formalize delivery and operational flexibility that Lake County needs to run its augmentation plan and nascent water enterprise, while making clear that major storage projects such as Box Creek remain long‑term and subject to extensive permitting, financing and engineering work.