MOUNT VERNON — Residents in Mount Vernon’s west end have expressed concerns about their neighborhood being in a floodplain for more than a decade.
Speaking to the Knox County commissioners in February, Mayor Matt Starr characterized it as being “since forever.”
That means residents are paying high costs for flood insurance. Yet, they are not confident that the Federal Emergency Management Agency (FEMA) would help them in the event of a catastrophic flood.
The city has undertaken several efforts to mitigate the flood risk and manage its floodplain. Enrolling in the Community Rating System (CRS) can earn credit for those efforts and help residents lower their insurance premiums.
What is the Community Rating System?
CRS is a voluntary program through the National Flood Insurance Program. CRS ranks municipalities on a scale of 10 to 1 on how well they coordinate their floodplain activities.
Ten is the worst; one is the best. Residents save 5% on their insurance for each level a municipality moves up the scale.
“Right now, we are at a 10 because we have not actually met with our CRS coordinator,” engineering technician Nick Johnson told the council.
“In order for CRS to actually give us a rating, they need to visit and audit us in summer or spring. Once that audit happens, we will probably move from a 10 immediately to a Level 8, so instantly 10% off [residents’] insurance.”
We will probably move from a 10 immediately to a Level 8, so instantly 10% off [residents’] insurance.
Nick Johnson
City Engineer Brian Ball said CRS is a way to reduce premiums without actually constructing on the levee.
“This program, getting it started, just means we’re going to audit our paperwork and make sure that they [NFIP] know we’re doing a reasonable job on our permitting and running the program,” he said.
“This is a way to get the rates down without actually running into the West End with a bulldozer or a backhoe.”
“Then we’ll also think about things that are non-structural, which is like the State Route 13 project. We’re going to lower the riverbank about 5 feet, and that project will also potentially reduce flooding. That’s non-structural because we’re not building a structure like a levee.”
A city moves up the scale by removing hazards, certifying elevations, preserving open space, and mapping, among other activities.
“The great part is that we already do those in the engineering department. Every project that we do, we’re working toward these things,” Johnson said.
Boots on the ground elevation surveys
Teams have conducted elevation studies using a “risk-based approach” to remove properties from the floodplain.
The surveys recorded the lowest ground elevation for each parcel in the West End. Teams then compared them to FEMA’s base flood elevation (BFE).
The BFE is the height to which floodwater is expected to rise in a 100-year flood.
The results were coded green (low risk) to red (high risk).
Of the 633 properties surveyed, 179 fell into the very low to moderate risk categories (true). The remaining 454 fell into the moderate-to-very-high risk categories (false).
Johnson said the 179 properties could apply to FEMA to be removed from the floodplain and not have to pay flood insurance.
The survey results do not account for homes with basements. Ball said a basement adds risk, but the level could vary based on whether utilities are present.
The city is also doing a full-blown analysis of the floodplain.
“This computer model that we’re relying on was completed in 1975, so channels have changed, floods have changed,” Ball said.
“We don’t have firm results yet, but the idea is that the shape of the flood may change with this update that we’re working toward. We’ll know more about that next year.”
Other support efforts
FEMA requires a 15-foot zone free of woody vegetation to protect the stability of the levee bank.
Crews removed and sold 15 walnut trees and will use the money to cover the cost of cutting trees that are not sellable timber.
Another issue is a collection of tires that needs to be removed. Johnson said the city is working with the Ohio EPA to pick up, dispose of, and recycle the tires.
“They had a certain amount of tire requirement, and we far exceeded that,” he said.
Crews started another round of vegetation clearing in November and a topographic survey on Dec. 5.
“We started at the bridge of State Route 13 all the way to the Mount Vernon Bridge, and we’ve been basically just surveying lines across the banks to see erosion,” Johnson said.
