Flood plan for downtown eyed

Springdale City Council approves $89,000 contract for design

SPRINGDALE — The City Council took measures Tuesday night to help the owners of downtown property keep their heads above water. The members approved an $89,000 contract with FTN Associates for design of a flood retention plan.

Most of the area along Spring Creek as it passes through downtown lies in a 100-year flood plain, said Ryan Carr, a city engineer.

The goal is to keep the creek within its banks and underneath the culverts, not reaching street level, he said.

A retention pond to be built in the northwest corner of the Springdale Municipal Airport property will hold water as it drains upstream as part of the natural watershed area. Holding the water and the design of the pond will allow the water to be released more slowly and at a level Spring Creek can hold, Carr said.

“There is such a huge need for this, especially as development continues

“There is such a huge need for this, especially as development continues downtown.”

— Ryan Carr, Springdale city engineer

downtown,” he said.

Development changes the natural drainage patterns of the land, he said. Water doesn’t soak into areas such as concrete streets and parking lots. Rather, it runs off and into the watershed very fast.

The city worked with FTN for a feasibility study for the drainage. Some plans called for additional ponds, including one on the east side of the airport and another on Turnbow Avenue in the city’s industrial park.

The engineers who did the study determined one pond at the airport will prevent flooding.

The study also showed water would fully drain from the airport land within 30 hours. The Federal Aviation Administration requires all water gone in 48 hours, Carr reported.

Spring Creek runs underground as it crosses the airport property.

The Federal Emergency Management Agency defines a 100-year storm as one dropping 4.5 inches in an hour on an area of 10 inches in 24 hours, Carr said.

“In a sense, the floodplain is the full extension of the creek,” reads the FEMA website. “The 100-year floodplain is the land that is predicted to flood during a 100-year storm, which has a 1 percent chance of occurring in any given year.”

Mayor Doug Sprouse said Tuesday he didn’t recall reports of water entering any structures during the record storms and flooding in spring 2016.

But he did see the flood level of the creek with just a few inches of the bridge crossing on Huntsville Avenue.

FTN staff also will submit applications to FEMA to remove the flood plain restriction. The contract with the city includes $14,500 in fees to be paid to FEMA for the review of the application.

Carr pointed out construction of the pond will come in several years after engineering and design plans are reviewed by FEMA, the FAA and the Army Corps of Engineers, which controls the quality of ground water.