Based on the results of the flood study and research done since its completion, staff have determined that the most impactful and cost-effective action that can be taken almost immediately would be establishment of a sensor system that would allow warnings of imminent floods. Weather sensors would provide vital data that would foster a better understanding of the City’s hydrology, and serve as the trigger for a proactive emergency warning system that could provide valuable minutes needed to take actions to reduce property damage and potential loss of life. The sensors would monitor rainfall throughout the City and the levels of key waterways, triggering an alert when established criteria are met. The specifics of such a system would require additional development, and the threshold criteria would be refined as staff collect better hydrological data.

The costs of such systems range from $2,500 to $4,000 per unit with additional annual monitoring costs ranging from $600 to $800. Staff anticipates the need for 15 to 20 units located throughout the City. Additional units could be easily added to the network, as needed. The total cost, including installation, approximates, +/- $65,000 plus $2,000 annually for data transmission and monitoring.

Staff has identified such a system currently provided by a Virginia non-profit organization in partnership with the U.S. Department of Homeland Security. Preliminarily, this partnership has identified Staunton as an appropriate location in Virginia for implementation of the partnership’s system, based on the history of flooding in the City’s downtown area. Were the City to participate with the partnership in its current statewide project, a number of flood sensors may be provided to the City, at no charge per unit and with no operating costs. Upon project completion in November of 2022, the sensors would be left in place for the City’s continued use, with ownership of the sensors transferring to the City. At the same time, the City would assume annual operating and maintenance costs. By participating in this project, the City would greatly reduce its implementation costs.

Estimated Costs: $0-$65,000 up front and $2,000 annually.
Time of Implementation: June 2023
Effectiveness: This would provide an immediate benefit to property owners and other interested parties. It would also provide the City with data that staff can use for future mitigation efforts.

After another flood in the City, in August 2003, the City applied for and received a grant from FEMA through its Hazard Mitigation Grant Program to install flood shields and other floodproofing measures in businesses along Central and Lewis streets and in the Wharf area. Because of the historic age of many buildings and the elevation of businesses below ground level, the goal of this project was to reduce potential flooding in structures, but these mitigation measures were never intended to completely eliminate it. Since the early 2000s, flood shields have improved dramatically in both their ease of installation and their design and fabrication, including the use of lighter, more durable materials. Property owners in flood prone areas may be interested in implementation of the newer floodproofing technology, which would facilitate increased usage. Several funding sources may be available and may be combined, including grants, cost sharing arrangements and property owner contributions, with in-kind contributions to be made by the City. Flood shields are one useful mitigation tool available to property owners.

Estimated Costs: Previous flood shields/floodproofing project after 2003 flood included average grant funding of $23,000 for each of 10 businesses.
Time of Implementation: Applying for grant funding: 18 months; shield installation: 6 months.
Effectiveness: Shields are effective in repelling up to 3 feet of floodwaters. Shields cannot be built higher due to hydrostatic pressure of floodwaters against building foundations.

One very effective tool in the flood mitigation toolbox is public education. There are many simple, low-cost strategies that residential and non-residential property owners can implement to reduce the impact of flooding on their properties. Strategies range from keeping gutters and storm drains free of debris to elevating utilities in a basement. These strategies can greatly minimize damage and potential repair costs. In order for property owners to implement these measures, they first need to be made aware of them and provided with “how to” information. Public education compared to other mitigation options can be instituted quickly and consistently through existing outlets such as the City’s website, social media channels and engagement activities such as workshops for citizens that educate them on the floodplain, why flooding occurs, and how to mitigate its consequences. The benefit of public education for the City, besides being cost effective, is that it reaches a wide audience. This wide reach is especially important because as witnessed with last August’s storm, flooding in the City affects not only those who live in the floodplain.

Estimated Costs: $0 to $5,000, annually
Time of Implementation: Immediately and ongoing.
Effectiveness: Helps prevent nuisance and basement flooding, and provides tools to property owners to be better prepared for larger events

A tunnel maintenance and improvement program would maximize the capacity of the existing tunnels that convey Lewis and Peyton creeks through downtown. Such a program would include an inspection and maintenance of the tunnels, along with possible improvements to them to mitigate “chokepoints,” like the confluence of Lewis and Peyton Creeks underneath the Wharf parking lot. The next step in establishing such a program is a thorough study of the tunnel system, addressing three primary areas:

1. Structural
   • Determination of structural soundness and repairs needed
   • Detailed mapping and geometry
   • Recommendation of repairs needed
2. Hydraulic
   • Identify areas requirement debris removal
   • Construction plan for removing debris
   • Identify additional access points needed for debris removal, future inspection, and maintenance
   • Develop detailed hydraulic model based on mapping
   • Identify existing utility crossings and other areas with the greatest adverse effect on storm water flow; determine their ability to be relocated/mitigated
3. Legal
   • Ownership of tunnel and access to it, particularly where it is not in the public right-of-way
   • Environmental permitting requirements for repairs and debris removal

These components are interdependent. For example, debris will need to be removed from some areas in order to provide complete structural inspection and mapping, and permitting and access requirements will need to be determined to develop the plan for debris removal.

The result of this investigation would be a fully designed, “shovel-ready,” one-time contract to remove existing debris and establish appropriate access points for future maintenance, repairs and improvements. It would also produce a recommended maintenance plan to be implemented after the initial project. Finally, it would produce a list of future improvements that could be evaluated and programmed for future development through the capital improvement plan process. Staff are not aware of a routine inspection or maintenance plan having been implemented or followed previously, beyond occasional limited inspections after suspected damage or major storm events.

To conduct such a detailed investigation/evaluation that includes design of a maintenance plan and reliable cost estimates, the City would need to procure the services of an engineering consulting firm. Due to the anticipated cost (approximately $650,000) and specialized nature of the work, a request for proposals would need to be issued once the scope of the project is fully developed and funding sources determined.

Estimated Costs: $650,000 for evaluation and design, and $7,000,000 for projects; ongoing maintenance costs are difficult to project.
Time of Implementation: It would be possible to have an investigation request for proposals prepared for late FY 2022 issuance, but follow-up steps would be highly dependent on the results of the investigation. Expenditures in FY2023 and FY2024 would be likely.
Effectiveness: A more detailed understanding of the condition of the tunnel would immediately improve decision-making, but the tangible hydraulic effects will take longer to develop as projects are implemented. The effects of the recurring maintenance program will take the longest to manifest.