Adams County approves Arvada intergovernmental agreement to replace aging Tennyson sewer line, 5-0

The Adams County Board of Commissioners on Jan. 28 approved an intergovernmental agreement (IGA) with the City of Arvada to replace an aging sanitary sewer on Tennyson Street and increase capacity for future development, voting 5-0 to adopt the IGA (RCU-2024-12) with 36 findings of fact and two conditions.

County planning staff presented the Arvada Tennyson North Trunk Sewer Improvements Project, describing the request as an IGA submitted in lieu of an Areas and Activities of State Interest (AASI, sometimes called a 1041) permit under Adams County development standards and regulations. Jen Rudder, Planning and Development Manager for Adams County, told commissioners the project was continued from a November 2024 hearing so the city could complete additional stakeholder outreach and floodplain analysis.

"The proposed wastewater pipeline improvements are considered an AASI," Rudder said, summarizing the county’s review criteria and the work performed since the prior hearing. The project would replace an existing sanitary trunk line installed in 1962 with a 42-inch gravity sewer where the existing line ranges from 21 to 30 inches in diameter, including trenching, testing and relocation of service lines.

City of Arvada officials said the upgrade is driven by aging infrastructure and capacity needs. Jacqueline Rhodes, Director of Public Works for the City of Arvada, said Arvada, county staff and private…