Mission Creek Adapting to Rising Tides

Project Team

Project Management Team: Port of San Francisco Partner Organizations: SPUR San Francisco Giants Bay Conservation & Development Mission Bay Development Group Commission SF Environment Office of Community Investment & Funders: Infrastructure Delta Alliance Port of San Francisco Consultants: SF Public Utilities Commission Alterra SF Department of Public Works ARCADIS City Administrator/Capital Planning RTKL SF Planning Department

Goals of the study • Understand vulnerability of Mission Creek • Develop sea level rise and stormwater adaptation concepts • Mission Creek • Bay Shoreline • Piers • Test and refine adaptation processes used in CA and the Netherlands • Develop capacity for multi-jurisdictional, multi- agency sea level rise planning • Exchange knowledge and best practices

Water surface elevation from sea level rise and storm surge

Mid-Century

End-of- Century

(Water levels in inches)

SLR Exposure in Mission Creek and Mission Bay • Potential significant impact from storm surge and sea level rise – even today • Four low points along the shoreline contribute to vulnerability in the near term • Entire shoreline protection too low in the long term

Assets of interest • Piers 40, 48 and 54 • 3rd and 4th Street bridges • Channel Pump Station • AT&T Park • Seawall Lot 337 Key vulnerabilities : • Structural and utility damage from flooding • Temporary reduced use  complete closures • Loss of historic resources • Higher maintenance costs

Mission Creek Adaptation Concepts

* Proposed Mission Rock Dev/’t

* AT & T Ballpark

* For Illustrative purposes only

*Creek Concept 1: Description: Raise the perimeter of the Mission Perimeter Creek shoreline to address vulnerable Shoreline low spots. Adaptation measures would include a mix of levees and seawalls. Protection Pros: - Bridges & approaches - Maintains tidal flow will have to be - Adjustable as sea replaced/elevated level rises - Long line of defense - Navigable - Mission Bay - Sewer overflow stormwater control system remains intact system will have to be modified

Cons: * For Illustrative purposes only

*Creek Concept 1: Perimeter Barrier

* For Illustrative purposes only

*Creek Concept 1: Precedent imagery

* For Illustrative purposes only

*Creek Concept 2 Description: Construct a tidal barrier at the mouth of the creek that can be closed during Tidal high tides and storm surge. Control Pros: Cons: - No need to increase - Will require more height of flood frequent operation as protection around the SLR rises, eventually creek leading to permanent - Maintains tidal flow closure - Maintains navigability - Risk of operational - Bridges protected failure

* For Illustrative purposes only

*Creek Concept 2: Tidal Control

* For Illustrative purposes only

*Creek Concept 2: Precedent Imagery

* For Illustrative purposes only

Description: *Creek Concept 3 Close Mission Creek from San Francisco Bay at the mouth of the creek with a levee or dam. Mission Creek could possibly remain connected to the Bay with a weir or Mission pipeline (i.e. like Lake Merritt) Lake Pros: - Altered tidal flow (Polder alternative) - New habitat - Water quality(?) recreation, and - Decreased navigability destination - Sewer system opportunities overflow / drainage - Levee is robust reconfiguration - Short line of defense - Mission Bay stormwater control system will have to be modified

Cons: * For Illustrative purposes only

*Creek Concept 3: Mission Lake

* For Illustrative purposes only

*Creek Concept 3: Precedent Imagery

* For Illustrative purposes only

Mission Bay Shoreline Adaptation Concepts

* For Illustrative purposes only

*Bay Concept 1: Description: Build a levee and/or sea wall along the Perimeter existing shoreline which will protect Mission Bay Shoreline Protection Pros: • Visual barrier • Limited space • Piers not protected requirements • Puts Mission Bay • Easy to fit in existing directly in a below sea infrastructure level situation • Robust: Limited failure risk

* For Illustrative purposes only Cons:

*Bay Concept 1: Perimeter Levee or Sea Wall

* For Illustrative purposes only

*Bay Concept 2: Description: Create a wide multipurpose levee Super Levee along the existing shoreline at a height to provide long-term safety

Pros: • Very expensive, requires • Fail-safe massive amounts of fill • Provides opportunities for • Piers not protected real estate development integrated with ecological protection

Cons:

* For Illustrative purposes only

*Bay Concept 2: “Super Levee”

* For Illustrative purposes only

Description: *Bay Concept 3: Use Third Street as the main line of protection by connecting buildings, roads Hybrid and elevated land to create a line of protection. The residential and commercial Approach development on the bayward side could (Hafencity, Hamburg) be modified to deal with temporary inundation.

Pros: • Difficult to implement • Unique residential and (permit) commercial waterfront • Limits availability of land to development opportunities develop • Different levels of protection (City vs Bay side)

Cons: * For Illustrative purposes only

*Bay Concept 3:

Hybrid approach (resilient waterfront) Living with water

* For Illustrative purposes only Before Flood

*Bay Concept 3: Hybrid approach (resilient waterfront) Living with water

* For Illustrative purposes only Flooded

*Bay Concept 4 Description: Bayward Create a levee or landmass in the Bay outboard of the piers to be used for new Development commercial and residential development, recreation and habitat development. The existing shoreline will not be modified.

Pros: Cons: • Very limited failure • Expensive risk • Requires filling of the • New adaptive zone Bay • Creates attractive location for development, recreation

* For Illustrative purposes only

*Bay Concept 4: Bayward Development

* For Illustrative purposes only

Adaptable and Resilient Piers

Approaches

for adaptable 2. FLOATING PIER 5. NON-TIDAL / LEVEE and resilient

piers

3. RAISE & REBUILD 6. DO NOTHING / ABANDON

Additional • Flood Risk Management - Level of Elements in Protection

Development • Community Resiliency

• Financing

• Governance

Next Steps • Draft Report for city review: End of October • Final report: November 19 • Workshop with Delta Alliance: January 2015 • SPUR magazine issue on Mission Creek: March 2015