County officials said they were expecting to have to answer many questions at Wednesday's public hearing regarding decertification of the Winslow Levee. However, of the approximately 30 people who attended the meeting, just two spoke and the hearing was over in about an hour.
The public comments will be sent along with information gathered by Navajo County offices and contractors to the Federal Emergency Management Agency (FEMA). The federal agency will officially decertify the Winslow Levee, an action that forces floodplain maps to be withdrawn for county residents living north of I-40 and east of North Park.
Since the levee failed twice this past winter, the county commissioned several studies into the causes as well as remedies. On Wednesday, Navajo County Public Works Director Dusty Parsons presented several recommendations to the public based on those studies.
"We can probably not get (all improvements) accomplished in five years. Rather than five years without any kind of protection, we're giving you this information to allow you to make decisions that you need to make," he said. "The Navajo County Public Works Department is going to make this our top priority."
Delph Engineering conducted a sediment survey and delineation study. Kent Delph said the redrawn flood maps would not affect anyone residing within city limits.
"We're proposing no changes to the city maps," he said.
The problem facing the county is that there is more than one solution needed to repair the levee so FEMA can recertify it. The build up of sediment along the levee, a process known as aggradation, has lowered the acceptable height. Parsons said sections vary in the height that they need to be raised, from 1-4 feet, along the 7.2 mile levee.
Knowing that the repairs will be costly and need to be made quickly, the county has asked the Army Corps of Engineers (ACOE) to perform a cost benefit study. If the Corps performs the study, then it would pay the bulk (possibly 75-percent) of repairs. If the Corps denies the request, the Navajo County Flood Control District would begin design options.
"If they (ACOE) do agree, then they would come in and build, which would solve a lot of those problems and it would be a structure that we would feel a lot safer with," Parsons said.
Regardless if the Corps takes over, the Flood Control District would begin removing tamarisk plants, an invasive species that blocks access to water resulting in more frequent flooding, by spraying herbicide by way of helicopter.
Besides lowering floodwater levels, removing tamarisk would be less costly than construction options, at first. However, Parsons said removal is temporary. The tamarisk root structure can be as deep as 20 feet. They reproduce quickly, partly by producing millions of seeds each year. Management of tamarisk is a long-term commitment.
Parsons presented two plans for the eradication of tamarisk, which include raising the levee depending on the extent of the area of eradication. Either plan costs about $2.2 million.
Thomas Chacon, one of the two residents who spoke, said that in his experience as a U.S. Forest Ranger, fire was more cost effective and "less drastic" than spraying a large area with chemicals.
Parsons replied that fire would be looked at as an option when the time comes. He added that removing the tamarisk would not be enough to recertify the levee.
Three areas require at least 3-4 feet of freeboard ‹ protection above the floodwater line ‹ for recertification. Nearly the entire levee needs to be raised at least one foot.
"We know that the probably the most feasible option is to raise the levee to get back to a certified levee. This may take us awhile," Parsons said.
Other options the county considered according to Parsons, were building a channel, purchasing all flood-prone property in Ames and Bushman acres and realigning 1,600-feet of the levee. Parsons said, the channel and property purchasing plans would probably be cost prohibitive.
Besides the ACOE, the county has asked U.S. Rep. Rick Renzi to help secure federal funds and Parsons said they are looking for other financial options so construction could begin as soon as possible.
The other resident to speak at the meeting was Dave Hartman, a property owner in Bushman Acres. He asked what was the cause for the change in certification.
"The (Winslow) City Council and Board of Supervisors don't want to change the certification from one year to the next, but because of the studies we have done in order to improve the levee, this information has brought out this new mapping," County Supervisor J.R. DeSpain (Dist. III) replied.
Delph said Winslow is most at risk of flooding when heavy rains strike the White Mountains causing the Little Colorado River tributaries (Jack's Canyon, Chevelon Creek, and Clear Creek) to fill.
A seven-member Winslow Levee Committee formed in July to address further issues with the levee.