DAPHNE, Ala. — Marlon Cook, a hydrologist with the Geological Survey of Alabama, said the D’Olive/Tiawasee watershed is a “perfect storm” for sedimentation.

About 80 people Wednesday attended an evening meeting at City Hall to hear Cook and other local experts speak on plans to correct water runoff threatening the watershed, a system that includes D’Olive Creek, Joe’s Branch and Lake Forest Lake.

According to Cook, a high slope has formed because the Eastern Shore sits at sea level, and land at the watershed’s edge rests at 70 meters. The slope in between acts as a giant stream for erosion and sedimentation to flow into the bay.

Lake Forest Lake receives 90 to 95 percent of sediment loads from tributaries, John Peterson, president of the Lake Forest Property Owners Association, said.

Cook said the largest impact of sedimentation is in Tiawasee Creek, where 1,000 tons of suspended sedimentation annually travel through a creek measuring one square mile.

David Yeager — former director of the Mobile Bay National Estuary Program — said such problems will cost between $5 million and $15 million dollars to fix.

“What we’re trying to do is seek a solution to a problem that’s 35 years old,” Yeager said.

“What we’re looking at today is how we move forward.”

Many residents in a public forum aired their views on the impact of erosion and sedimentation in the watershed.

“Something has changed (in D’Olive Creek) in the past two years,” Glen Huey, a Lake Forest resident, said. “One-third of my yard is useless.”

Huey’s backyard — which rests just beside D’Olive Creek — once was filled with green grass, he said; however, flooding has dumped sediment onto his property.

Don Prosch, another Lake Forest property owner, whose home overlooks Lake Forest Lake, said he’s tired of increasing mosquito activity at the lake’s east end.

“I’m concerned about health concerns …,” he said.

Daphne’s Public Works Department on Friday did not immediately return the Daphne Bulletin’s phone message  requesting information on its insecticide service, and whether the city is aware of perceived mosquito infestation near Prosch’s neighborhood.  

Contributing factors

Yeager identified six  factors that have led to erosion and sedimentation problems.

•Highly-erodable soil. Soil has reached this state due to its high amount of sand, according to Roberta Swann, interim director of the estuary program.

•High average rainfall (about 62 inches per year).

•Rapid growth and development.

•Zoning issues. Limited planning — for example, neighborhood developments situated far from grocery stores and malls — means an increase in driving, which leads to more parking lots and increased water runoff due to impervious pavement.

•Not following the Best Management Practices menu phases. For instance, a silt fence to filter sediment should be installed around the perimeter of a construction site; see other standards at http://cfpub.epa.gov/npdes/stormwater/menuofbmps/

•Upstream and downstream hydrologic modifications. An increase of impervious surfaces like parking lots and driveways lead to an incrase in water runoff, according to Swann.

•Lake design and capacity. The lake is the receiving body for all of the water flowing downstream from the creeks.

“A lot of the erosion is coming from the storm events like Hurricanes Katrina, Ivan, and Gustav,” Ashley Campbell, the city’s site containment inspector, said.

Erosion from storm events formed due to sandy soils retaining water and acting like fluids, according to Swann.

The Geological Survey of Alabama, Alabama Department of Emergency Management, Fish and Wildlife Service, and Environmental Protection Agency are working together on this problem, Swann said.

Request for qualifications

Yeager said the process of a request for qualifications, regarding a comprehensive water management plan, would take just over two years. A request for qualifications is an assessment of the cost to correct a problem. A team of engineers will survey the watershed and provide an assessment. A request for the necessary funds can then be made to Alabama Legislature.

The proposed schedule is as follows:

•Issuance on Nov. 3

•Pre-submittal conference, Dec. 3

•Statement inquiry deadline, Dec. 15

•Statement receipt closing date, Jan. 30, 2009

•Award exclusive negotiating rights, April 15, 2009

•Public outreach and education, October through January 2010

•Delivery of comprehensive water management plan—January 2010

Yeager said construction on infrastructure would begin three to five years from now.

“This is not going to happen overnight,” he said. “It’s a multi-year approach.”