Smith Island Clean Water Project
Location Smith Island, MD
Client Somerset County Sanitary Commission
Size 0.04 MGD
Costs $22.3 million
Date of Completion Ongoing
Services #Civil / Site Engineering #Construction Services #Consulting #Structural Engineering #Water / Wastewater Engineering
Sectors #Consulting #Funding Assistance #Government #Infrastructure #Wastewater Systems
In 2013, GMB provided the Somerset County Sanitary Commission with a Preliminary Engineering Report (PER) to evaluate the performance and physical condition of the existing wastewater facilities located on Smith Island, Maryland, consisting of two (2) wastewater treatment plants with surface water discharges and three (3) pump stations that serve the villages of Ewell, Rhodes Point, and Tylerton. The Sanitary District was experiencing significant challenges with the operation and maintenance of the aging facilities.
The existing wastewater facilities have exceeded their design life expectancy and are inadequate to perform as required. The treatment plant at Ewell, in particular, has physically corroded and deteriorated beyond repair. It is extremely impractical to maintain the operation of the existing treatment plant while simultaneously attempting to repair it and upgrade it.
The PER took into account environmental impacts, land requirements, construction problems, and sustainability considerations (water & energy efficiency, green infrastructure, and coastal resilience).
Following the recommendations of the PER, the County commissioned GMB for the design of a combined 40,000 gallons per day Enhanced Nutrient Removal (ENR) wastewater treatment plant (WWTP) capable of treating the wastewater flows from all three (3) villages, located adjacent to the existing Ewell WWTP. This involves discontinuing the operation of the WWTP on Tylerton and transmitting its wastewater flow to the new WWTP at Ewell. A new approx. 1 mile-long sub-aqueous force main will convey wastewater from Tylerton to Rhodes Point. Additionally, GMB designed upgrades to each of the three (3) pump stations with new above-ground, duplex pumping systems better suited to the environmental design conditions, along with a standby emergency generator and SCADA communications for improved reliability.
GMB assisted the County with obtaining approvals and funding (approx. 93.5% Grant) through USDA and MDE; final design of the project began in 2016. A timber deck was constructed in 2019 to support the new WWTP and the pump stations were completed in April 2023. The subaqueous force main and WWTP upgrade construction contracts are currently ongoing.
