City of Cottage Grove Selects Carollo Engineers To Lead Storm Drainage System Master Plan

City plans ahead with 20-year stormwater strategy to support growth, environmental protection

The City of Cottage Grove has selected Carollo Engineers to develop a comprehensive Storm Drainage System Master Plan that will guide the City’s infrastructure planning and stormwater management strategy over the next 20 years.

This initiative comes at a pivotal time for the city, which has recently surpassed the 10,000-resident threshold. This milestone triggers new regulatory requirements under Oregon’s MS4 (Municipal Separate Storm Sewer System) program. Additionally, Cottage Grove has adopted low-impact development guidelines and a Total Maximum Daily Load (TMDL) implementation plan, emphasizing the need for an updated, forward-thinking approach to stormwater management.

The project will include a thorough assessment of the current stormwater system, identification of capital improvement needs, and development of a long-range plan that aligns with Oregon’s Public Facility Planning standards (OAR 660-011) as well as requirements from the Department of Environmental Quality, Department of Land Conservation and Development, and other regulatory bodies.

Cottage Grove’s stormwater system spans more than 30 miles of drainage lines and includes approximately 600 catch basins, along with several open channels and ditches. With low-impact development policies already in place, the City is poised to further enhance its stormwater infrastructure, supporting sustainability, growth, and resilience.

Carollo’s approach to the plan emphasizes proactive planning, data-driven analysis, and sustainable infrastructure strategies. The firm has a robust history in stormwater drainage master planning, offering wide-ranging solutions that address both current and future infrastructure needs. With expertise in hydrologic and hydraulic modeling, Carollo has developed and updated stormwater master plans for municipalities throughout the Northwest and nationwide. The firm’s deep local knowledge, supported by a national network of experts, positions Cottage Grove to benefit from effective, data-driven solutions tailored to meet the city’s specific needs.

The City and Carollo will work closely with local stakeholders to integrate community feedback into the plan to reflect the values and priorities of Cottage Grove residents. The plan will also focus on strategies to improve water quality, protect local ecosystems, and mitigate the impacts of flooding, contributing to the long-term environmental health of Cottage Grove.

“Our goal is to create a flexible, future-ready plan that enables Cottage Grove to manage stormwater effectively while supporting community growth,” said Carollo Project Manager Kurt Robinson. “We’re proud to partner with the City to develop a plan rooted in long-term environmental stewardship.”

City officials view this effort as a critical investment in the community’s future well-being.

“As our city continues to grow, developing a stormwater system that protects people, property, and the environment is essential,” said Public Works & Development Director Faye Stewart. “We look forward to working with Carollo to create a plan that not only meets state and federal requirements but also reflects our community’s values around sustainability, environmental stewardship, and smart infrastructure planning.”

In addition to assessing existing infrastructure and projecting future needs, Carollo will perform a rate study and assist the City in identifying funding sources while prioritizing capital improvement projects that deliver meaningful benefits to the community.

The Storm Drainage System Master Plan is expected to be completed by fall 2026.