Location: Seattle, WA
Owner: Seattle Public Utilities

OCI was the prime for the award-winning Venema Natural Drainage System project. The design project retrofitted six residential city blocks with roadside bio-retention cells and underground injection control wells (UICs) providing water quality treatment, infiltrating runoff from the street, and reducing runoff peak flow and volume. As all the construction is within the City of Seattle ROW, the project involves close coordination with SDOT following the SIP process.

Using the experience OCI staff gained over the years working on LID on projects with SPU, SDOT and other city agencies; OCI was responsible for the hydraulic modeling of the bio-retention swales using MGSFlood, QA-QC, and delivery of PS&E for the storm drainage, utilities and street improvements. All deliverables met the submittal requirements of SPU and the SDOT SIP process.

The project featured the use of bioretention stormwater planters to reduce flow volumes computed using MGSFlood modeling. OCI followed the requirements for SDOT SIP and City of Seattle Stormwater code. All work was designed within the ROW, while being sensitive to neighbors’ concerns.

In 2015, the project won the ASCE Seattle Chapter Local Outstanding Civil Engineering Achievement (LOCEA) award in the Small Project category.

In 2016, the project won the American Council of Engineering Companies (ACEC) Best in State: Gold Award for successfully fulfilling client needs.