Helen Keller Elementary

Lake Washington School District, Kirkland, WA

Wetlands and steep slopes required creative solutions to stormwater management for this replacement project.

Market

K-12 Schools

Services

Civil Engineering

Land Surveying

Features

Replacement school on existing site

New water & sewer service

Bioswales

StormFilter vault

Wetlands and steep slopes required creative solutions to stormwater management for this replacement project.

This replacement school is located on the existing 8-acre school’s playfield and required a phased construction approach to allow the existing school to operate while the new facility was constructed. The second phase of construction involved demolition of the old school to make way for a parking lot and play fields.

The site is complicated by wetlands and a 70 foot elevation change over the site. AHBL provided topographic and boundary surveys and a wetland delineation to identify the wetland buffer. AHBL’s stormwater design protects the sensitive areas on site by ensuring that stormwater flows remain constant after construction. Stormwater is detained in Stormtech chambers and released at a rate that matches pre-developed conditions. Stormwater on the site requires enhanced water quality treatment because the stormwater discharges to a wetland on the south side of the site. AHBL designed bioswales and a StormFilter vault to provide enhanced water quality. AHBL also designed new water and sewer services and a fire loop around the building.