Revised, study-based, digital flood insurance rate maps for Northwest Pima County have been generated, and the Federal Emergency Management Agency is seeking public comments on them.
An appeal and protest period is open through Jan. 13, 2010, according to the Town of Marana.
Keith Brann, engineer for the town, told the council last week that those who protest "would have to propose alternate scientific study." To date, there is one formal protest, from Waste Management regarding its refuse operations on Ina Road above the Santa Cruz River, and two informal protests from the federal Bureau of Reclamation and the Central Arizona Project.
Waste Management is "disputing our interpretation of the results from our study," Brann said Tuesday. He inquired, worked with study consultants, and toured the Waste Management site.
"We agree with their protest," Brann said. "We made a mistake. I agreed we misinterpreted the data." Marana plans to "champion" the Waste Management challenge, and submit a cover letter indicating its error to FEMA.
BuRec and CAP "have objected to the methodology we have used" to update the floodplain mapping. "They are arguing on some of our technical analysis," Brann said. "The town does not agree with them. We stand behind our study." Letters of protest from the two agencies are being forwarded to FEMA, Brann said.
Public notices of the new flood insurance maps have been published, and open houses are planned during 2010. Two web sites – those of Marana and Pima County – have links to electronic versions of the new maps, and Brann showed the council and audience on the big screen how to manipulate information.
"The nice thing about this for the actual public, you can enter any address in Pima County" and identify its floodplain status, he said. "It's a very potent tool."
The town "has worked diligently on shaping these maps, including a drainage study of the Tortolita Fan watershed that affects a large part of Marana," a release said.
Two years ago, FEMA draft maps did not accept manmade structures that may function as levees, among them the Central Arizona Project canal, I-10 and the Union Pacific Railroad. A town-funded study of the entire Tortolita Fan was conducted by CMG Drainage, with "dramatically less" housing development within the less-protected floodplain. Study results have been accepted by FEMA and incorporated into flood insurance rate maps.
On the new maps, "massive areas of the town" – among them the Dove Mountain community, Continental Ranch and Gladden Farms – "are not going to be put into a floodplain," Brann said.
When properties are identified within the floodplain, the town is prepared to provide "individual recommendations to affected properties" about options, Brann said.
Work maps from the Town's Tortolita Fan study, and the FEMA preliminary maps, can be found at http://www.marana.com/index.aspx?NID=592. Paper copies of the maps and the town's Tortolita Fan study can be found at the town's engineering department, located at 11555 W. Civic Center Drive in Marana.
FEMA is expected to address any protests early in 2010, commencing a six-month period for final public comment. "That gives us a lot of time to do outreach," Brann said.
If FEMA "holds to their schedule," the new flood plain maps would become effective Sept. 30, 2010, Brann said.