Salem, Oregon - In November of 2008, voters within the Salem-Keizer Public School district passed a $242.1 million school construction bond - one of the largest in Oregon history. As part of the bond, the community wanted to increase school safety, renovate and upgrade existing facilities, ensure independent oversight for bond projects and build four new schools to alleviate overcrowding. Salem-Keizer Public Schools set up a construction bond campaign to share how the bond addressed these issues and to build strong community relationships.
Two of the new schools - Straub Middle School and Kalapuya Elementary School – were built in West Salem. The new schools will benefit the community in multiple ways, including providing healthy and safe environments for educational programs and by providing proximity to West Salem neighborhoods. The new school construction also included extending Wilmington Avenue to connect the two schools to the neighborhoods on the opposite side of the construction area.
This roadway extension required the need for stormwater management. Salem-Keizer Public Schools worked with Youngman Locke Engineers to find a low impact development (LID) solution. They were working under a tight timeframe to complete construction and open the new schools on schedule. This required a solution that could be installed quickly.
“The LID solution was desired because it decentralizes the treatment of jurisdictional environmental requirement,” said Ron Hudkins, P.E., with Youngman Locke Engineers. “It also has the additional benefit of lessening the peak water runoff volume.”
Unlike conventional stormwater management practices that seek to collect, convey, treat and then discharge urban runoff off-site, LID takes a more holistic approach. Rainfall is managed close to the source with integrated management practices (IMPs) dispersed uniformly throughout the site. LID site design emphasizes conserving natural areas and minimizing impacts to the natural environment.
The UrbanGreen™ BioFilter from CONTECH was the chosen solution for the project because it could provide a high level of treatment and partial reduction of runoff volume. The UrbanGreen BioFilter is a compact, versatile and reliable alternative to conventional designs and was a cost-effective solution to the alternative.
An internal high flow bypass weir is also a standard design feature of the Urban Green BioFilter. This configuration eliminates the extra high flow bypass inlet structure that would be required if an alternative biofiltration product was chosen. This greatly reduces installation time while providing additional cost savings to the school district. An additional cost advantage is that the activation of each BioFilter unit is included within the purchase price. This includes the cost of the plant and the labor to install the tree or shrub selected by the design engineer. First year maintenance of the system is also included to ensure that a healthy root system is established.
“One site challenge was the hilly nature of the site,” said Hudkins. “Wilmington Avenue traversed the entire elevation change of the site, leading to varying grades at the basin locations - from 2% to 9.5%. This called for a new design for the UrbanGreen BioFilter.”
Emery & Sons installed 22 4’ x 6’ UrbanGreen BioFilter cartridges in just 6 weeks. The project construction went quickly because they were able to install the units, piece by piece, as the product manufacturing was completed by a local precaster.
A CMP detention system composed of 336 LF of 75” diameter, 16 gage, Aluminzed Type II CMP was also utilized on this project. The footprint of the system was 24’ X 108’.
'We were pleased with the final outcome of the project,” said Jay Remy, Director of Communications and Community Relations at Salem-Keizer Public Schools. “We have two new schools open, serving over 1,000 students per day in a great learning environment.'
More than 1,000 people attended the ribbon cutting and open house events at Kalapuya Elementary School and Straub Middle School on September 2, 2011. Students, parents and community members filled the new schools and went on student-led tours of the new facilities. In addition, 11 schools in Salem-Keizer recently reopened following extensive renovations during the summer.
Salem-Keizer Public Schools
Youngman Locke Engineers
Emery & Sons