By July, survey crews working for Monroe County will know something about every one of nearly 500 canals in the Florida Keys.</p><p>The third phase of an ongoing $300,000 project calls for contractors to run bathymetric surveys -- measuring the depths of canal bottoms -- as part of a countywide canal restoration program to improve water quality.</p><p>"These waters have been identified as impaired waters that have to be cleaned up," Mayor George Neugent said at the Jan. 16 County Commission meeting.</p><p>As proposed, information gained from canal inspections could lead to five demonstration projects that test each of five systems to improve water quality in canals that feed into nearshore waters.</p><p>The federal Environmental Protection Agency and the state Department of Environmental Protection funded the study phase, but the county may have to pay at least part of the cost of the demonstration projects, estimated at $2.5 million to $5 million.</p><p>"There are different types of fixes for different canals," said Rhonda Haag, county sustainability program manager.</p><p>The county will target canals that could be restored by projects testing:</p><p><LI> Using a weed-rack barrier to block floating seaweed.</p><p><LI> Installing an air-bubble curtain that would have a similar effect.</p><p><LI> Removing harmful sediment from a canal bottom.</p><p><LI> Pumping to improve water flow into and from canals.</p><p><LI> Backfilling canals that were dredged too deeply, often as a source for building fill.</p><p>"An awful lot were dug way too deep," Haag said, leading to the death of grasses and other desirable bottom-dwelling ecosystems.</p><p>"Up until this point, we have not gone out to stick things on the [canal] bottom and find out what's there," Haag said.</p><p>Since the "vast majority" of Keys canals are privately owned by landowners along the banks, County Commissioner Danny Kolhage wondered if that could slow the program. Neugent said even where the canal bottom is privately held, owners usually cannot prevent boats from navigating on state waters in canals.</p><p>If property owners along a canal with poor water quality want to help fund a pilot project to help qualify for matching funds, Haag said, "That could probably bump them to the top of the list."</p><p>Neighborhood or community associations interested in contributing toward pilot programs can send an e-mail to Haag-Rhonda@monroecounty-fl.gov.</p><p><B>Dredge proposal</B></p><p>The issue of dredging privately owned canals may reach the County Commission in a separate matter sometime this year.</p><p>An amendment to the county's land-use plan that would allow limited canal dredging under specific circumstances was endorsed by the Monroe County Planning Commission in November.</p><p>Owners of property on Walker's Island, east of Duck Key near mile marker 63, have submitted a plan to dredge an existing channel so it can accommodate larger boats at an eight-unit development project.</p><p>Existing local, state and federal laws effectively ban dredging, even for maintenance, in most Keys canals.</p><p>Backers of the proposal are working on a presentation to the County Commission but no date for the item has been scheduled, said Mayte Santamaria, assistant planning director.