Bend staff say stormwater master plan shows outdated data; recommend weather stations, CIP prioritization and standards updates

City of Bend staff told the Utilities Public Advisory Group in December that the stormwater master plan confirmed a need for better, more current hydrological and precipitation data, and that improved monitoring will inform project prioritization and standards updates.

“We found that that data is 50 years old,” Austin (City engineering) said when summarizing the master-plan findings, noting that the age of the data is a key justification for investing in more monitoring. Staff said the plan lays out a path to standardize recommended weather stations and flow monitoring so new, higher-quality data can be used in future design standards.

Staff described how advisory-group feedback helped shape a scoring matrix used to prioritize capital improvement projects (CIPs). The city expects the draft CIP list to be ready for review once consultant staffing and schedules allow; staff said consultant resource constraints have put the schedule behind expectations.

City staff said the master plan also examined climate change impacts and hydrology, and that follow-up monitoring and data collection would support future updates to regional design guidance such as the Central Oregon stormwater manual. “The big message of the master plan is: hey, we have outdated data and we should have efforts to improve that,” Austin told members.

On regulatory and standards fronts, staff summarized recent permit-driven changes. The municipal stormwater permit now requires erosion-control measures on smaller disturbances: the city now treats sites that disturb 5,000 square feet or more as requiring formal erosion-control documentation and photos at key milestones, staff said. For small single-family lot work, staff described a template-based submittal process that avoids formal engineering plans and a permit fee if owners submit the required photos and attestations; staff said the city will still perform a required end-of-project inspection under the permit.

Staff outlined work on underground injection control (UIC) standards for dry wells and drill holes. Based on consultant work and advisory feedback, the city is moving to geographically targeted requirements—more stringent where perched groundwater or two-year time-of-travel to drinking-water wells is a concern, and more permissive elsewhere. Staff said they are seeking to reduce the former 500-foot private-well restriction to 100 feet for non-municipal wells while retaining a two-year time-of-travel protection for municipal drinking-water wells.

The group also heard about outreach to local businesses to prevent illicit discharges. City staff contracted EcoBiz to reach roughly 30 auto, landscape and restaurant businesses with a certification checklist; staff said the program is intended to be educational and that they may need to add incentives to increase business participation.

Several members emphasized the need to tie the master plan to funding. Advisory members noted Bend’s stormwater fee is relatively low (staff reported single-family residential stormwater charges under $8 per month in Bend) compared with peer cities, and that a stormwater rate study will be required to fund recommended projects and any higher service levels. Staff said the stormwater rate study will follow the master plan and level-of-service discussions.

Staff said next steps are to finalize the CIP prioritization (consultant schedule permitting), recommend monitoring equipment standards, and return to the advisory group for a final CIP check and for policy discussions on drainage-and-density and level-of-service.