CANAL IN KEY LARGO’S ROCK HARBOR UNDERGOING RESTORATION

Clean material is delivered to the staging site, then placed onto a barge and spread out through the length of the canal. KRISTEN LIVENGOOD/Monroe County

Monroe County is underway with its water quality improvement and restoration project on canal No. 84 in Rock Harbor in Key Largo. The restoration project is funded by a Florida Department of Environmental Protection Keys Stewardship grant. 

Canal No. 84 is rated as a poor water quality canal that does not meet the state’s minimum thresholds for dissolved oxygen levels in the canal.  For this project, 32 truckloads of decaying organic vegetation were removed during the past 60 days. The organic removal process removes the decaying material on the canal’s bottom that affects oxygen and can also cause a strong sulfur (rotten egg) odor. 

Backfilling of the canal areas that are too deep started earlier this month, with 235 truckloads of fill material anticipated to be deposited into the canal before it is finished.  Backfilling raises the canal bottom to an optimum depth (about 7 feet) to allow maximum flushing and tidal flow in and out of the canal. These restoration techniques will increase the amount of oxygen in the canal, increasing its health and the amount of marine life in it. The project is scheduled to be completed in June.

In addition to the project, the residents will be installing and maintaining an air curtain to keep seaweed from re-entering the canal once the project is complete. The county also received a Hurricane Irma grant from the state Department of Economic Opportunity for breakwater repairs outside of this canal, which are scheduled to begin this year.

“This canal restoration project has been five years in the making. The residents have been extremely helpful partners every step of the way,” said Rhonda Haag, Monroe County chief resilience officer. “These improvements are anticipated to restore the impaired waters of the canal and bring the dissolved oxygen levels up to meet marine water quality standards.”Additional restoration projects for other poor and fair water quality canals in the Florida Keys will come forward as additional funding allows. Canal restoration improves the overall health of nearshore waters. To learn more about canal restoration, visit www.monroecounty-fl.gov/canals.