Caribbean Avenue Green Street
|Sponsoring Agency||City of Sunnyvale|
|Counties||Santa Clara County|
|Public or private land?||()|
|Location (lat/lon)||37.417214, -122.017091|
|Location Description||The Project area is located in northern Sunnyvale at the southern portion of the San Francisco Bay.|
The Caribbean Avenue Green Street Project will retrofit a stretch of an existing arterial street with Low Impact Development water quality improvements, increase visibility and access to the San Francisco Bay Trail, and serve as an opportunity to educate Bay Trail users and high tech company commuters about the connection between urban landscapes and the Bay. Specifically, the Project will eliminate one of three travel lanes on each side of a stretch of Caribbean Avenue in north Sunnyvale (approximately 120,000 square feet), and the excess road area will be used to construct approximately 11,620 square feet of bioretention rain gardens to capture and treat polluted road runoff and provide more than 40 parking spaces for Bay Trail visitors. The resulting street will be a notable demonstration of Sustainable Streets concepts – incorporating water quality treatment with multi-modal travel and pedestrian and bicyclist safety improvements. Integrating the rain gardens with Bay Trail parking will also create a unique watershed educational setting for hundreds of daily visitors and area employees.
Part 2 - Detail
This Project will retrofit an existing arterial street with Low Impact Development water quality improvements, increase visibility and access to the San Francisco Bay Trail, and serve as an opportunity to educate Bay Trail users and high-tech company commuters about the connection between urban landscapes and the Bay. Specifically, the project will eliminate one of three travel lanes on each side of a stretch of Caribbean Avenue in north Sunnyvale (approximately 120,000 square feet) where the excess road area will be used to construct approximately 11,620 square feet of bioretention rain gardens and provide more than 40 parking spaces for Bay Trail visitors. The bioretention areas will be designed to capture and treat the regional stormwater permit required runoff volume, consistent with regional Green Street expectations. The rain gardens will be planted with California natives and adapted plants chosen for their low irrigation requirements, pest resistance, and proven performance in rain gardens. The Project is scalable and project and treatment areas can be adjusted, if needed.
This Project is located in the Moffett Industrial Park, Sunnyvale’s largest employment center with more than 30,000 employees and housing corporate campuses for companies such as Yahoo!, NetApp, Juniper Networks, and Lockheed Martin. Many of these company employees utilize the Bay Trail for recreational purposes throughout the day. Caribbean Avenue is also a commute route for area employees from highways 237 and 101. Additionally, the Project is located at the entrance to Sunnyvale’s EcoCampus, housing the City’s Water Pollution Control Plant and the Sunnyvale Materials and Recovery Transfer Station. Construction of the rain gardens and location of Bay Trail parking in this area will create an inviting gateway that connects the area’s employees with the Bay and the critical environmental services provided at the City’s EcoCampus. Moving the Bay Trail parking from its current, somewhat hidden location next to the City’s Water Pollution Control Plant to Caribbean Avenue will increase its visibility and can result in additional Bay Trail users, increasing community awareness and appreciation of the Bay. The City will also explore the possibility of connecting the rain garden irrigation system with the City’s recycled water system.
This Project complements other City and Santa Clara Valley Water District projects in the area that will improve flood protection, construct new trails, and improve pedestrian and bicyclist safety. Studies show that climate change will affect sea level and precipitation patterns (frequency and intensity). Collectively, these projects can result in important climate change and adaption benefits. Singularly, this Project can contribute to climate change and adaption benefits. This Project can demonstrate how bioretention rain gardens, by intercepting and capturing roadway runoff, can increase stormwater management capacity. The newly constructed rain gardens can also reduce urban heat island effects in the area through the reduction in heat reflecting paved surfaces and increasing native vegetation that can provide a natural cooling effect in the area.
The resulting street will be a notable demonstration of Sustainable Streets concepts and create a unique watershed educational setting for hundreds of daily visitors.
Not implementing this proposal will further substantiate the challenges identified by local agencies in 2013 Bay Area IRWM Plan related to Regulatory Compliance and Financial and Funding Challenges. Local agencies, including Sunnyvale, will continue to struggle with how to meet increasing stormwater requirements, specifically related to green infrastructure planning and implementation, and agencies will continue to grapple with green infrastructure implementation with a lack of information and understanding of the costs associated with these types of projects. Additionally, the long term water quality benefits provided by the bioretention areas designed to treat street runoff and remove sediment and other pollutants of concern will not be realized.
Water Quality Benefits: It is commonly known that public streets in the Bay Area contribute polluted stormwater runoff to local waterways and, in turn to San Francisco Bay. The EPA’s “Protecting Water Quality from Urban Runoff” identifies primary urban runoff pollutants as sediment, sediment-bound pollutants such as heavy metals, PCBs, and pesticides, and hydrocarbons and oil and grease from motor vehicles. These pollutants can harm fish and wildlife, kill native vegetation, and adversely impact recreational areas. Through the construction of approximately 11,620 square feet of bioretention areas, the project will improve water quality by providing for landscape based treatment and pollutant removal of untreated road runoff prior to flowing to the Bay.
Stormwater and Flood Management Benefits: Through the construction of bioretention areas, the Project will reduce the quantity of stormwater flowing to the Bay. By design, bioretention features capture and retain stormwater and promote infiltration. Underdrains are included to facilitate release of treated stormwater when retention capacity is exceeded.
Resource Stewardship Benefits: This Project creates a visible access point to the Bay Trail that intersperses rain garden treatment areas with public parking for Bay Trail users. Relocating the parking area from a hidden location next to Sunnyvale’s Water Pollution Control Plant can increase awareness of the Bay Trail among area employees and visitors, increase Bay Trail use, and increase watershed and Bay stewardship. Interpretive signage will be placed at key locations highlighting the benefits of the rain gardens, educating visitors about the connection between the urban landscape and the Bay, and the importance of Bay protection actions.