Diversion project will get Grafton off the flood map
GRAFTON, N.D.—It's easier to keep track of the years Grafton hasn't been flooded by the Park River, Mayor Chris West said when asked how often the city was ravaged by the unpredictable waterway.
Wearing a bright yellow vest with Grafton 2013 flood fight on the back on Thursday, he and others looked over an approximately $45 million flood diversion project that they hope will eliminate the need to fight flood waters ever again.
"It's just kind of crazy to watch how it progresses," West said, adding construction is on schedule.
Once finished in fall 2019, the project is set to take Grafton out of the flood map and, in turn, eliminate the need for flood insurance, West said. Not only will it improve safety, but it also could encourage economic development.
"We won't have to fight floods, we won't have to spend community dollars working on flood projects and time and resources," he said. "The benefit of it is exponential."
By the numbers
Massive machinery started moving dirt on the 3.2-mile diversion channel in March, though pre-construction work began last year, West said. The planned channel that will run west to east just north of Grafton will carry water from the Park River.
The project also includes 12.5 miles of tie-back levees to protect the city, said Jon Markusen, a project manager from engineering and planning firm KLJ. There also is work being done south of town.
Construction of the diversion and levees will cost $25.1 million. The remaining costs went toward land acquisition, engineering and other expenses, West said.
Tractors and trucks will have to cut out a trench for the diversion channel that, on average, will be about 16 feet deep, West said. The top will be about 300 feet wide with a bottom of 50 feet in width.
About 1.5 million cubic yards of dirt will be removed for the project. That would fill almost 455 Olympic swimming pools, or about 107,000 dump truck loads.
A $32 million grant from the North Dakota State Water Commission will pay for most of the project, while a half-cent sales tax increase approved by voters in 2015 will generate about $12 million.
Off the map
Grafton has become well-trained in fighting floods, thanks to repeated events over the years, West said. Last year, the city built 700 yards of emergency levees in between existing dikes as the Park River threatened residents.
Three waterways feed into the Park River west of Grafton, which is prone to unpredictable flooding. In 2013, the year noted on West's vest, the city had to fill sandbags in anticipation for three floods, West said.
That also was the year the city had two of its top three historic crests—May 22, 2013, set the record and May 1 took third, both with a crest just over 16 feet, according to the National Weather Service.
With the exception of this year and 2017, each year in the 21st century has made the historic crest list for Grafton at least once—the list keeps track of the top 35 floods, and seven floods in the last 10 years are in the top 10.
"There got to be so many there," Markusen said.
The city will need to go through one more spring before the diversion project is expected to wrap up in October 2019.
West estimated community members and businesses pay a combined total of about $1 million a year in flood insurance, West said. With the flood diversion project taking Grafton out of the flood zone, homeowners can spend that money elsewhere.
The diversion project also will make property more valuable, and the lowered risk of flooding could make it easier for businesses eyeing Grafton to move there, West said.
Finally, it gives the city more time to focus on economic projects, he said. City staff plan to gather input on Grafton's potential for development.
"I've been working on this project as mayor for about a year," West said. "It is rewarding to see it finally take shape and finally get the protection the community needs."