In 2008, at the request of the Santa Monica community, a project was initiated to examine the portion of Ocean Park Boulevard west of Lincoln Boulevard to Neilson Way. The community requested solutions to issues based on scale, character, health, safety, sustainability, landscaping, accessibility and circulation. After several years of planning and collaboration between community members, the City of Santa Monica and other local stakeholders construction for the Ocean Park Boulevard project began in December 2011 with a groundbreaking ceremony. From Neilson Way to Lincoln Boulevard, Ocean Park Boulevard will be turned into a “Complete Green Street,” resulting in a better performing, enhanced streetscape that is pedestrian and bicycle oriented, attractive and reduces urban runoff discharges into the Santa Monica Bay.
Key elements of the project included: wider sidewalks, over 100 trees, improved landscaping, a drip irrigation system, crosswalks, traffic signal improvements, parkway/stormwater biofilter swales and infiltration areas, storm improvements and more. While searching for a stormwater solution, the City and Kimley-Horn and Associates, Inc, the engineer on the project, turned to Contech Engineered Solutions for help. Both longterm clients, they knew Contech would provide a strong level of expertise in stormwater and low impact development (LID) engineering.
As a solution, Kimley-Horn chose to utilize four basins of ChamberMaxx® ranging from 945 CF to 4,590 CF of storage, two basins of 84” perforated corrugated metal pipe (CMP) with approximately 4,000 and 10,000 CF of storage and one basin of 24” perforated CMP with approximately 250 CF of storage. Ideal in a shallow footprint, the open-bottom plastic ChamberMaxx allows infiltration into surrounding soil, effectively achieving runoff reduction requirements. By utilizing subsurface infiltration, space is preserved for development or green spaces above, runoff is reduced or eliminated and groundwater recharge can occur. Furthermore, ChamberMaxx’s light weight allows for installation by hand, rather than by heavy equipment, providing a green and economical solution.
“The CMP installed very smoothly,” stated Randy Slane, Construction Manager with Arcadis, the construction manager on the project. “Excel Paving Company is a great contractor and installed the large, 7’ diameter pipe and connected it with an excavator in less than an hour, like clockwork.”
Throughout the project, a few challenges were encountered, such as installation of the pipe in tight spaces, utility conflicts and grade issues. Due to utilities buried in the area, it was imperative that the pipe size varied throughout the project in order to meet the depth requirements. In addition, the footprint was extremely restricted so the width and length of each pipe section was carefully considered. There were also concerns about corrosive soils in the area so, as a solution, the CMP was coated with polymer.
At completion, the project included improvements to over a half mile of vehicular right of way, more than 6,000 linear feet of sidewalks and the 4th Street overpass. The end result has benefited the Ocean Park neighborhood and the entire Santa Monica community by providing a working model of sustainability, multimodality and low-impact street design.