City of Lorain Black River Dredged Material GeoPool Pilot Study

Coldwater is assisting the City of Lorain with a pilot study to test the use of GeoPools as a dewatering application for material dredged from the Black River. The City of Lorain has received a Healthy Lake Erie Fund grant from the State of Ohio in coordination with Ohio Department of Natural Resources and Ohio EPA for the construction of the Black River Dredged Material Reuse Facility. The pilot study was designed to test an innovative method for dewatering dredged material. The GeoPool dewatering system is a scalable, modular sediment dewatering solution used to rapidly dewater dredged material with a low solids content. The GeoPool was used to clarify dredged slurry using natural settling, fabric filtration, and dosing with non-toxic polymers.

The GeoPool is comprised of a system of rigid steel frames linked together to form a circular structure which is then covered in a geofabric that prevents the passing of sediment particles while allowing decant water to freely filter through. Sediment sourced from the Black River was used to implement the pilot study.

The results of the study indicate that the textile dewatering technology is superior to basins and geotextile tubes, based on the smaller footprint needed and the improved effluent clarity, settling rate, throughput, and sustainability. The system efficiently processes often difficult to manage fine-grained sediments.

The study continues with the assessment of low-cost, low-contact dewatering scenarios such as the seasonal freeze-thaw cycle.  Additionally, Coldwater is assisting with the evaluation of cost-effective residual solids reuse as agricultural soil, residential garden soil, brownfield cover soil, and engineered fill.

The GeoPool test site is located on a former steel manufacturing property acquired by the City of Lorain, known as the Reclamation Site. The City is currently completing restoration projects within the Reclamation Site, focusing on the restoration of areas previously used by the steel mills for storage of steel processing by-products.