Collaborative approach transforms Sussex County’s Wastewater Treatment Capabilities
At a glance
Sussex County, Delaware, United States, operates the South Coastal Regional Wastewater Facility, which treats and disposes of wastewater in the region. The facility is part of the county's broader effort to provide sewerage services to areas with ageing septic systems and manage expected growth. GHD oversaw the design, bidding, and construction phases of the project, assisting the client in overcoming complex challenges, enhancing efficiency, and implementing automation and advanced technologies.
The challenge
Sussex County, Delaware, needed to upgrade its wastewater systems to modernize aging infrastructure, improve environmental outcomes and support their growing population. The County’s goals included expanding maximum monthly average daily flow treatment capacity, expanding peak flow hydraulic capacity, providing additional flow equalization, upgrading solids handling systems, decommissioning obsolete systems and improving aeration.
Our response
GHD was retained by Sussex County for the planning, design, and construction management and inspection for the expansion of the South Coastal Regional Wastewater Facility (SCRWF) to 10 mgd capacity.
As part of the planning effort, GHD performed a comprehensive flow and load analysis, developed and carried out a supplemental sampling plan, developed a hydraulic model of the existing facility, and created a calibrated BioWin process simulation model of the existing facility. The hydraulic and process simulation models were used in the evaluation and development of recommendations for the new facilities.
The expansion of the Sussex County South Coastal Wastewater Facility involved several important upgrades to improve its overall operation. The existing mechanical screening and grit removal systems were updated, and old tanks that were no longer in use were converted into flow equalisation tanks. New secondary and tertiary treatment units were added, alongside renovations to the existing treatment facilities. Improvements also included a new effluent pump station, upgraded sludge storage and dewatering systems, an enhanced electrical power distribution system with a new emergency generator, and the modernisation of the plant’s supervisory control and data acquisition (SCADA) system to streamline operations.