Flood control plan presented to council

The Maricopa City Council got its first look this week at a three-phase plan to build a massive flood-control channel that would open 3,200 acres of land within the city for development.

The tract of land is located along the Maricopa-Casa Grande Highway and stretches seven miles to the south, at times exceeding a mile in width. The area is adjacent to the North Santa Cruz Wash in what is called a 100-year floodplain, meaning that every year there is a one-in-100 chance of a flood.

Devastating floods hit this area in 1983 and again in 1993.

“When a flood hits this wash, we are looking at 9,800 cubic feet of water per second,” said Chris Salas, Maricopa’s transportation manager.

Currently, there are no homes in the extensive tract of land because statutory limitations placed on land in a floodplain make development nearly impossible, according to Salas. However, several developers have submitted preliminary plans for future subdivisions in the area and the city owns a 145-acre parcel in the tract slated as the site of a new city hall.

The city hall complex is scheduled to break ground by November 2011, according to the design firm behind the project, Abacus Project Management Inc.

However, Salas said before the project begins the city acreage must be secured from flooding. “We are not allowed to build public facilities in a flood zone,” he said.

To remove the entire 3,200 acres from the floodplain, the city plans to construct a seven-mile channel stretching from the Maricopa-Casa Grande Highway to the city’s border with the Gila River Indian Community.

To accomplish this, the city staff is working with developers on an agreement involving landowners in the floodplain giving the land needed to build the channel to the city. Landowners have also agreed to help cover a portion of the maintenance and construction cost, according to Thomas J. McDonald, an attorney representing the landowners involved in the agreement.

The project was initially estimated to cost $25 million, but Salas said city staff members believe that the project will come in at a far lower figure when it is put out to bid.

To spread out the cost, the city is looking at a three-part plan for construction of the channel.

The first phase would remove the land owned by the city, along with a large amount of additional land, from the flood zone.

The second two phases would pull land on the north and south boundaries of the wash out of the flood zone.

However, before any construction begins, the city must submit an application for a conditional letter of map approval (CLOMAR) to FEMA, according to Salas.

A CLOMAR is granted to an entity after plans to remove an area from the flood plain are approved by FEMA.

Maricopa’s overall plan is intended to remove the entire 3,200 acres from the flood zone, but a provision that prohibits the plan from impacting neighboring property could delay the process.

“We have to work with the Gila River Community to determine what we do with the flow of this channel where it terminates on their land,” Salas said. “We can’t impact their property with this project.”

One possible solution would be for the city to extend the flood-control channel to the North Santa Cruz Wash bridge, providing protection for reservation land as well as city property.

“At some point this issue is going to change from one that is technical to one that is political in nature,” Salas said.