Mission Creek Stormwater Park

• Treat stormwater runoff from 9.6 acres of adjacent streets and open space.
• Achieve bioswale capacity to treat 100% of 90th percentile, 24-hour storm events, equivalent to 0.75 inches of rain in 24 hours.
• Remove dust, fine grained soils, and oils from stormwater runoff.
• Reduce labor and maintenance needs by creating a centralized water treatment area and implementing microtopography to stimulate water movement through gravity.
• Stabilize the waterfront edge for overflow during high tide events.
• Reduce water consumption with a greywater irrigation system.
• Support local ecological health using native plantings.
• Provide spaces for passive and active social uses such as strolling, outdoor dining, socializing, enjoying waterfront views, game day activity, and everyday traffic from visitors and residents.
• Accommodate spill-over social activity from game days and adjacent retail uses.
• Separate public from private uses.
• Create protected circulation along the waterfront for cyclists and pedestrians connecting to the San Francisco Bay Trail.

• The 1.2-acre park includes 39,725 sf of hardscape and 12,218 sf softscape, of which 6,482 sf is green infrastructure—primarily bioretention basins. In total, there are 31 plant species in the park, 23 of which are native to California.
• The 3 vegetated bioretention basins are planted with 74% native grasses and shrubs, including California native species hummingbird sage (Salvia spathacea), Pacific reedgrass (Calamagrostis nutkaensis), and red fescue (Festuca rubra). The basins create the park’s defining geometries and alignment, separating the waterfront promenade from the Mission Bay condominium complex to the southeast.
• 9 additional planter beds with deciduous shade trees extend the bioswale geometries at various points along their border. Species include gingko (Ginkgo biloba) and California box elder (Acer negundo) along with native grasses and shrubs such as Mound San Bruno coffeeberry (Rhamnus californica ‘Mound San Bruno’), Heart’s Desire California lilac (Ceanothus gloriosus ‘Heart’s Desire’), and Mendocino reedgrass (Calamagrostis foliosa) 
• 15,638 sf of shoreline stabilization along the waterfront edge includes 11,063 sf of vegetated buffers planted with salt tolerant native groundcovers like jaumea (Jaumea carnosa) and native shrubs like dwarf coyote bush (Baccharis pilularis ‘Pigeon Point’) and pussy willow (Salix caprea), which reinforce the slope and reduce wind exposure in the park.
• 4 boardwalks cross the rain gardens and extend to 3 waterfront promontories viewing Mission Creek Channel, immersing pedestrians in the planting experience. These wooden crossings rest on soil mounds that arch over culverts connecting segments of each rain garden basin.
• 10 seating nooks with wooden benches are embedded within the rain garden geometry, providing visitors with quieter moments of sensory immersion within the park.
• Paved promenades on either side of the park’s vegetated central axis provide dedicated circulation along the waterfront for cyclists and pedestrians. These promenades connect the site with the San Francisco Bay Trail, an ongoing effort to connect the San Francisco Bay shoreline with a continuous trail. 
• A picnic area anchors the northeast entrance of the park. This shaded area includes 3 picnic tables over permeable paving and a drinking fountain sheltered by 3 native oaks. This picnic area, along with other seating in the park, accommodates game-day tailgaters as well as everyday traffic from visitors and residents.
• Rain garden plantings and geometries define intimate gathering and rest areas adjacent to the condominium building frontage from an open promenade along the waterfront edge. This configuration provides residents with indoor privacy through a planted screen along the adjacent residential building while creating access to outdoor open space amenities.
• 72 new streetlights—including 30 tall streetlights with power outlets, 21 bollard lights, and 21 ground-level luminaries—illuminate the park at night.
• A pump station will connect an additional 364,632-sf drainage area to the bioretention basins once it is completed.
• Planting beds will be irrigated with recycled greywater supplied by the Mission Bay reclaimed water system once the system is connected.

• The City of San Francisco implemented the Stormwater Management Plan (SWMP) requirement in 2003. This requirement is meant to minimize stormwater pollution in areas where storm drains flow directly into receiving water bodies (e.g. bays, creeks, rivers). The Mission Bay Development is not connected to San Francisco’s combined stormwater system, so stormwater must be treated before being directed into Mission Creek Channel. The SWMP requirement was implemented in San Francisco while Mission Bay district was partially under construction, requiring developers to update the design of stormwater systems. At that stage, the street design had been finalized and could not be redesigned to integrate bioswales on the sidewalks. The most efficient way to adhere to the SWMP requirements was to create a centralized stormwater system treating runoff from adjacent streets in a single area. Mission Creek Stormwater Park was conceived for this purpose. At the time, the use of centralized bioretention basins in public spaces was a fairly new and innovative proposal for the City. City requirements were being developed throughout the design approval process, so the proposal had to shift with new requirements as they were written. This resulted in longer than typical design and engineering phases, and a need for ongoing communication with the City. City officials expressed feeling proud about the quality of the project—from their perspective the ongoing communication, feedback loops, and design reviews were key in achieving these results.
• The park’s bioretention basins are designed to treat stormwater runoff from 9.6 acres of adjacent streets and open space through a pump station. However, the pump station was not constructed in tandem with the park. The planned pump station that will connect the basins to the surrounding stormwater runoff system is pending approval from the City as of mid-2024. The pump station is expected to come online 18 months or more after construction begins. As a result, the pump station will likely not be online until at least two years after completion of the park.
• The pump station became necessary to treat the amount of stormwater required by the City. First, the City required a design where the stormwater fed into the basins through gravity alone, without pumps. However, in order to efficiently connect current stormwater infrastructure to the bioswales without having to drastically alter existing stormwater systems surrounding the park, use of pumps became imperative.
• Engineers designed subtle changes in the topography of the basins to direct water flow. During construction, it was challenging for contractors to understand and implement the intended microtopography of each bioretention basin, and some of the basins had to be adjusted after initial construction as a result.
• Although the bioretention basins are meant to be protected from social use, children and dogs enjoy playing between the plantings and the topography, which results in maintenance concerns, negatively impacting the mortality of some plant species and causing quick erosion of the microtopography.
• In 2023, the Mission Bay Development Group granted the park to the City, and since then, San Francisco Recreation & Parks is responsible for park maintenance. The quality of the maintenance is lower, with at least five weed species identified in the basins and tall grasses during the spring, as they were not pruned in the winter.

Regionally Sourced Mulches, including stone and sustainably harvested redwood
FSC Curb and Decking
FSC Western Red Cedar
FSC Site Furnishings

Project Team

Owner: Mission Bay Development Group
Landscape Architect: CMG Landscape Architecture
Irrigation Designer: Brookwater Irrigation Consultants
Civil Engineer: Freyer & Laureta, Inc.
Electrical Engineer: F.W. Associates, Inc. 
Structural Engineer: Hohbach-Lewin, Inc.
Lighting Designer: studio | three twenty one
Contractor: Hosely Corporation

Role of the Landscape Architect

 The landscape architect oversaw the design of all planting, flatwork, and site furnishings and collaborated closely with the Civil Engineer to create high-performing public infrastructure in a complex urban environment.