An engineering study of three drainage creeks in Washington that are listed as flood zones on new federal floodplain management maps should be completed in about 16 weeks.
But after the initial work is done, the Federal Emergency Management Agency (FEMA) could take another eight months to review the data and make a ruling, city council members were told last week.
The council approved an ordinance authorizing a contract with BFA consulting engineers to conduct the studies of three creeks that run through town — the Washington Crossing/Bedford Center Creek, Fifth Street Creek and City Park Creek and establish base flood elevations (BFEs) for those unnumbered A flood zones.
“Once the BFEs are established letters of map revisions will be submitted to FEMA for review,” Raymond Frankenberg II, BFA president, said in a letter to city officials.
In addition, at the city’s request, BFA will research and complete steps necessary to “correct” errors on the Missouri River flood insurance rate maps for the south bank near the Highway 47 bridge, Frankenberg said.
As noted in past discussions, portions of the three small creeks have been piped underground and that revised base flood elevations could result in some property being moved out of flood zones.
“These are approximate zones and are not based on reality,” City Engineer Dan Boyce said at last week’s meeting.
BFA will evaluate all existing hydrologic conditions including the stormwater piping system now a part of those approximate zones, Boyce said previously.
Jim Briggs, city administrator, said city officials have been getting calls from some property owners who have been contacted by banks telling them they are required to have flood insurance. “We believe most of those are in these areas,” Briggs told the council.
“We have to do this for citizens,” remarked Councilman Joe Holtmeier.
“This is a follow-up to the new FEMA maps that we have to do,” said Mayor Sandy Lucy.
Under BFA’s proposal, the firm will undertake each study and complete that work before proceeding to the next task. The firm anticipates beginning with Fifth Street Creek followed by Park Creek, Washington Crossing/Bedford Center branch and Missouri River correction. Each task is expected to take four weeks. After each is completed the data will be submitted to FEMA for review.
FEMA anticipates taking a minimum of 32 weeks to review each task.
The estimated cost for all the studies is $31,100, which includes $2,500 in general survey work and plan review, $9,750 for the Fifth Street Creek study, $7,800 for the Park Creek phase and $5,525 each for the Washington Crossing/Bedford Center branch and Missouri River correction.
The new FEMA flood maps replace the maps that have been in use since 1982. The process to adopt new flood zone maps has been under way since 2001 when FEMA commissioned an engineering study by the URS firm. In 2007, the city hired another firm, the Farnsworth Group, to review the URS study but found nothing substantially wrong.