Escondido, California, often called the “heart of northern San Diego,” is located just 30 miles outside of downtown San Diego and 20 minutes from the Pacific Coast. Although “Escondido” means “hidden” in Spanish, it is a vibrant city rich in history and culture where more than 151,000 residents call home.
The urban center of Escondido contains a network of concrete and earthen storm drain channels and pipes that convey rains to the Escondido Creek flood control channel. The Spruce Street channel collects water from a 1.24 square mile area of the city. This runoff is carried through the Escondido Creek watershed all the way to the San Elijo Lagoon and ultimately to the Pacific Ocean. One key waterway near Spruce Street and the Escondido Transit Center was difficult to maintain and regularly flooded, threatening nearby businesses and causing vector control and water quality issues. Restoring the natural waterway is the city of Escondido's goal in the Water Quality Improvement Plan (WQIP) of the local watershed.
The city of Escondido, in partnership with lead designer Michael Baker International and contractor Palm Engineering Construction Company, Inc., successfully led a multi-year, multi-agency effort to clean, restore and reconfigure the 2,000-foot-long channel by increasing channel capacity, removing downstream barriers that obstruct flow and constructing protective flood walls along certain channel banks.
The Spruce Street Drainage Improvements Project included:
- Clearing and repairing a trapezoidal concrete channel between West Third Avenue and Spruce Street.
- Installing new maintenance access points to an underground box culvert along Spruce Street near Second Avenue.
- Rehabilitating an earthen channel which flows from Grand Avenue, under West Valley Parkway, and along the Sprinter tracks behind the Escondido Transit Center to the Escondido Creek flood control channel.
- Removing accumulated soil and vegetation, improving infrastructure, removing an unused pedestrian bridge and replanting channel banks with native, climate-appropriate vegetation.
- Constructing two permanent maintenance ramps to improve Public Works’ access to the newly rehabilitated earthen channel sections.
Michael Baker designed the project to provide for sustainable indefinite operation by creating a stable channel that is low maintenance, offers flood protection, is aesthetically pleasing and supportive of beneficial uses. The team analyzed the greater watershed needs and designed the channel to provide an improved level of service and alleviate system-wide flooding issues; minimize capital expenditures by improving upon existing infrastructure; and improve ease of maintenance with new access ramps.
The Spruce Street Drainage Improvements Project included multiple elements, as discussed below.
Coordinating Among Multiple Agencies
The Spruce Street Drainage Improvements Project was under the jurisdiction of several agencies including United States Army Corps of Engineers (USACE), North County Transit District (NCTD), Regional Water Quality Control Board and CA Fish and Wildlife. Coordinating permissions from these entities was a key component of the project’s development. The project also was subject to the California Environmental Quality Act (CEQA), which requires state and local government agencies to inform decision makers and the public about the potential environmental impacts of proposed projects and to reduce those environmental impacts to the maximum extent feasible.
Working Within a Sensitive Habitat
Throughout the design, there was an emphasis on restoring the channel to closely resemble the native habitat while still providing adequate drainage capacity. The channel was restored and reconfigured to minimize imperviousness and protect existing natural features. Stabilization efforts were creatively implemented to meet erosion control requirements while still maximizing sustainable design. More specifically, a proprietary concrete flex anchor mat was installed along the maintenance ramp access areas to provide a rigid and stabilized drivable surface that still allowed for planting along the side slopes and channel bottom.
Most of the project sits on a sensitive habitat area. To restore the site, the team removed all exotic species and replanted the area with appropriate native/riparian species. Freshwater marsh was removed to improve channel capacity and flood protection but was replaced with native tree and shrub wetland species that offered higher quality habitat than what previously existed. Plant establishment will continue to be monitored over the next few years.
Overcoming Adverse Conditions
While highly successful, the project was not without its challenges. During construction, the channel endured several slope erosion issues prompted by heavy rains during the wet season. The design team, contractor and the city all worked together to resolve the issue as timely as possible to avoid any scheduling setbacks. Additional coordination with the geotechnical engineer of record was required to better assess the situation and provide recommendations for the slope repair. Despite the heavy rain, the entire project team coordinated a solution to repair the damages and construct the channel according to plan.
Engaging the Community
To ensure community support, the team closely coordinated with key stakeholders and launched a public awareness campaign. Public meetings were held, during which residents and business owners could view and provide feedback to the overall project, as well as view exhibits that communicated the preliminary location of the channel improvements, a traffic control concept, a landscaping concept and other conceptual design information. The City of Escondido created a dedicated landing page to keep the public and key stakeholders up to date on project information and progress.
Realizing the Benefits
The Spruce Street Drainage Improvement Project provides a safe and clean environment and has allowed the local community to realize the desired project benefits, including:
- Better flood control with new channel walls.
- Cleared impediments to water flow.
- Improved pedestrian safety with sidewalk bridge.
- Easier maintenance with new access ramps.
- Wetland habitat planting and oversight.
In addition, the Spruce Street Drainage Improvement Project overlapped with the Escondido Transit Center Active Transportation Connections Project (ETC ATC) on the northside of West Valley Parkway where a new pedestrian bridge provided safe walking and biking in the vicinity of the North County Transit District (NCTD) Sprinter Station at the Escondido Transit Center. The adjacent but distinct projects overlapped with the Spruce Street Drainage Improvements Project in some areas such as design, permitting and construction for cost efficiencies.
The Spruce Street Drainage Improvement Project has resulted in less flooding, improved water quality, restored natural habitat and increased public safety for the City of Escondido. The project has also been recognized within the industry and was recently named the Project of the Year in the Sustainability/Green category by the American Public Works Association (APWA) San Diego & Imperial Counties Chapter.