SAV mitigation plan will be required to install subaqueous force main between Tylerton and Rhodes Point

0.8 acres impacted, 4.8 acres to be addressed with removal of phragmites

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PRINCESS ANNE — The Maryland Department of the Environment is expected to formally approve a mitigation plan to protect underwater grasses which may be disturbed during construction of the Smith Island Clean Water Project.

The Somerset County Sanitary District is replacing and upgrading the wastewater treatment plant in Ewell with an enhanced nutrient removal (ENR) system.

As part of this, the Tylerton treatment plant will be closed and a force main run underwater to Rhodes Point so approximately 6,000 gallons per day of wastewater can then be pumped to the new facility.

The pipe will impact 0.8 acres and with MDE approval six times that area will need to be addressed or 4.8 acres through the removal of phragmites and planting of salt meadow hay and smooth cordgrass. The Sanitary District will monitor the site for long-term sustainability and replant the native species if necessary.

Likewise, if there is a storm event damaging the new vegetation that will be assessed and replanted.

The mitigation site is 18 acres of tidal wetlands owned by the county.

In the draft agreement the project will be considered successful if 85% of the plants survive. The plan is to spray and cut phragmites in the early fall of this year or 2022.

The SAV (submerged aquatic vegetation) plan has verbal and email confirmation from the regional tidal wetlands planner but formal acknowledgment from MDE was pending last month before the Sanitary Commission.

Sanitary District General Manager Tony Stockus said it will be “pricey” at $40,000 per acre “but it will allow us to move forward with the project.” The new treatment plant over is 90% grant funded at $9.261 million and will remove nitrogen and phosphorous by 80% and 90%.

Closing the Tylerton plant will also allow for the reopening of shellfish harvesting in Merlin Gut.

It is estimated it will take two months to install the pipe. George Miles & Buhr is the engineering firm leading this project and it prepared the mitigation plan for MDE.