Southern Crisfield Flood Mitigation
The Building Resilient Infrastructure and Communities (BRIC) Direct Technical Assistance (DTA) team formed a flood mitigation strategy to protect the City of Crisfield from flooding. The strategy will help address the risk of flooding that comes from a tidal storm surge of 5 feet, referenced to the North American Vertical Datum of 1988 (NAVD88). This project will protect the city from the 1% annual-chance tidal flood. Based on sea level rise projections it will also protect the city from a 2% annual-chance tidal flood in 2050. This strategy includes a wide range of mitigation actions to surround the city with a tidal flood protection barrier. The barrier would keep water from coming in from the bay. At the same time, it will allow rain and storm water to drain out to the bay during coastal flooding and rainfall events.
Crisfield will carry out its flood mitigation strategy through two independent but adjacent projects (Northern and Southern).
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The Southern Crisfield Flood Mitigation Project has been submitted to FEMA for funding in the nationally competitive BRIC grant program. This project will build a continuous tidal flood protection barrier and improve internal drainage. These upgrades will affect Chesapeake Avenue and part of the city to its south. They will provide an initial level of protection from a 3.5-foot NAVD88 storm surge. This protection will be limited by physical limits to raising the elevation of Chesapeake Avenue and Maryland Route 413. Note that other components will be built to an elevation of 5.0 feet NAVD88.
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The Northern Crisfield Flood Mitigation Project will extend the tidal flood protection barrier north of Chesapeake Avenue. It will also improve drainage in the same area. It will tie into the tidal flood protection barrier built by the Southern Crisfield Flood Mitigation Project at either end of Chesapeake Avenue. This will help it protect the city from the 5-foot NAVD88 storm surge. The city will likely seek funding for this project in the next cycle of BRIC funding, in Winter 2024-2025.
All project designs and improvements presented in this subapplication are conceptual. Design will be finalized after more studies are completed as a part of the Phase 1 deliverables for each stage. Additional activities in Phase 1 of each project include permitting, property acquisitions, preparation of construction documents, and other program and project management activities. Phase 2 activities for each project include construction of the project elements and project closeout.
Project Info:
1. What will this project do?
This project will protect the city of Crisfield from tidal flooding, storm surge, and wet weather flooding. To achieve this, it will install a mitigation strategy that will raise existing infrastructure, such as roads and bulkheads, to create a coastal barrier. This will also improve Crisfield’s internal drainage. This will keep the water out during high tide and storm surge. It will also get the water out during wet weather events. A range of drainage improvements will make this possible. They will convey the storm water more effectively to the constructed and restored wetlands for storage. That water can then be pumped out into the bay.
2. What are the components in the project?
The project includes many coastal and internal drainage improvements. It will elevate roads, berms, and bulkheads to create a coastal protection barrier; replace and install tide gates where needed; and restore and build coastal wetlands to build up the capacity of the drainage system. The project will improve drainage systems throughout the city as well. This will help pipes and ditches convey water to storage areas. Pump stations will be installed at the downstream end of the wetlands. They will pump the excess flow out into the bay during wet weather events. An underground storage vault is also planned for the downtown area as there is not any available land to set up wetlands or other green infrastructure. The details of these mitigation components will be finalized during the Phase 1 design of the project if Crisfield receives the BRIC funding.
3. Will the project increase flooding outside of the city?
No, this project will not increase the flooding outside the project area. The common misconception is that displacing the water from Crisfield will flood the areas outside of the project. The reality is that we are displacing the water that is coming from the Chesapeake Bay, which is a massive body of water. Based on rough calculations, displacing the volume of the city of Crisfield from the Chesapeake Bay will raise the overall level of the bay by 0.02 inches. This is about half of the height of an average grain of sand. There will be no noticeable difference in the height of flood levels outside of the project other than what is expected from sea level rise.
4. What would happen if a storm overtops the project?
Hydrologic and hydraulic studies during Phase 1 of the project will develop the design of an internal drainage system. This includes extra pumping capacity if needed to drain floodwaters from within the flood protection barrier. This would take no more time than what would occur if the same storm occurred under existing conditions.
5. What will raising roads look like?
The crown of the road will be raised up to 3 feet higher (based on location in the city) than the existing pavement elevation. The pavement will slope away from the crown 12 to 16 feet. It will lead into a drainage swale on either side of the road. Grading will then tie into existing yard elevations. Driveways will be re-graded where needed to connect to the road. Detailed design during Phase 1 will define the specific grading needed for each property along each road to be elevated.
6. Will raising roads cause flooding in my yard?
No. The project will be designed so that the roads being elevated will come with drainage infrastructure that is the right size to handle the flooding/ponding that could occur along the road. This will prevent flooding from occurring on road-front properties along the roads that will be raised. Projects that are applying for BRIC program funding must not increase the risk of flooding in areas surrounding or upstream of the project.
7. Will this protect the city from more severe storms due to climate change?
Yes, this project will protect up to 5 feet NAVD88. Within the last 40 years, the highest level of flooding that we could find a reliable record for was during Hurricane Sandy, which produced flooding of 4.5 feet NAVD88. This means that the project would have protected the city against every storm event from the past 40 years. It also would continue to protect the town from all but the largest storms into the future.
8. What kind of protection will this project provide? What about future data?
This project is designed to protect the town from the 50-year, or 2% annual-chance, storm event in 2050. We chose 2050 as the target year because the projections of sea level rise for the Chesapeake Bay strongly agree in multiple climate models.
9. What data were used to develop the project?
The layout of the project is based on the drainage assessment preformed in 2021 and LiDAR elevation data collected in 2021. The drainage assessment identified the water and flood elevations from the tide and storm event scenarios that included storm surge (extra flooding from wind pushing up extra water). These elevations were used to look at the LiDAR data to determine where the flooding would occur at each level of storm event. These data account for increased tidal heights that come from sea level rise.
10. Who will maintain the project? How much will maintenance cost?
The city is responsible for maintenance of the project. It also must maintain the current drainage system within rights of way owned by the city. The council will be presented with a comprehensive plan in May. This plan will recommend ways to maintain the city’s drainage system (including this project). It will also suggest an equitable way to fund the needed maintenance.
11. What will happen to properties outside the perimeter of the project? This project will not cause more flooding outside of its target area. It will provide points that other projects can tie into for the future, such as the county coastal protection berm. This will give future efforts a chance to protect more properties in the city and county.
12. Will I have a chance to learn more about this project? Will there be opportunities for public input?Yes, we plan to support learning about the project’s funding sometime after August 2024. After the funding award, public input sessions will be held as part of the Phase 1 planning.
13. I have information about an aspect of this project that I would like to share, or I still have concerns and would like to talk with someone about the project.
Please reach out to Grant Administrator Jen Merritt at 410-968-1333 or jmerritt@crisfieldcityhall.com to schedule an appointment to talk further.
14. How can I help?
You can help by reporting flood impacts each time a flood occurs. This information can help the city receive funding to assist with flood mitigation. Unfortunately, reporting impacts once does not show repetitive flooding. You can report flood impacts at CrisfieldFloodMitigation.com.
Current Drainage System:
1. If the ditches can’t handle flood water now, how will the situation be better with this project?
This project includes coastal protection and a large amount of drainage improvements. The restored wetlands will build capacity that the drainage system has not had before. New drainage pipes and swales will allow the flow to get to the storage locations. This will be done along with the replacement and installation of tide gates. The tide gates will help keep the bay from coming back up into the system. The city is also working on a maintenance plan for the existing system and the new infrastructure that will be installed.
2. How does this plan integrate with the current ditch system in Crisfield?
The proposed project includes concepts for improving the city’s existing ditch drainage system. The concepts will be further developed during initial project hydrologic and hydraulic analysis and design. Upgrades and routine maintenance of the city’s entire drainage system are a key piece of the proposed flood mitigation system.
3. Why can’t we fix the tide gates now?
The city is currently evaluating the repair or replacement of six tide gates to protect against coastal flooding during “sunny day” flooding events, which now occur often. Tide gates alone are not enough to protect against the more extreme, wind-driven flood events that the city now suffers multiple times each year. It also can only protect to a water height of 1.75 feet, which occurs many times each year.
Project Cost & Timeline:
1. How much does this project cost? Who is paying for it?
The total project cost is $40,022,095.85. This includes the project cost of $38,116,281.76 plus interest that will accrue from a loan the city applied for from the Maryland Department of Emergency Management (MDEM). The city must match $3.8 million of this cost for the Southern Crisfield Flood Mitigation Project. The Northern Crisfield Flood Mitigation Project will likely need a similar amount. The table below lists how the city will or hopes to meet the cost match requirement.
2. What will happen if Crisfield does not get a FEMA grant?
If the city is not awarded this grant under the current round, we will continue to look for other sources of funding and apply for grants until we are successful.
3. What is the project timeline?
