DOP Submersible dredge pumps

The DOP350 will dredge at the contaminated site near the walls and docks


Location: Randle Reef in Hamilton Harbour, Ontario, Canada
Period : Q3-4/2018
Product type : DOP350 with leveler head
Contractor : Fraser River Pile & Dredge (GP) Inc.

Precision dredging at an environmental remediation job on the Great Lakes

Fraser River has been contracted by Public Works and Government Services Canada to carry out the cleanup of the largest Canadian contaminated site on the Great Lakes. The location is Randle Reef in Hamilton Harbour, the western tip of Lake Ontario. The site is approximately 60 hectares in size, and contains some 695.000 m3 of contaminated sediment.

The leveler head is jet water assisted boosting the production

Fraser River’s scope of work on the clean-up includes dredging of a half a million cubic meters of contaminated sediment, disposal of the sediment in an engineered containment facility, as well as the downstream water treatment.

The DOP submersible dredge pump is manouvered by a wire crane

To ensure all contaminates are dredged and to avoid over dredging of the underlying clean soils high accuracy dredging is required. As such Fraser River is currently taking delivery of a project specific cutter suction dredge. Prior to the arrival of this dredge onsite Fraser River has procured a DOP350 to conduct dredging within close vicinity to infrastructure including sheet pile walls and docks.

The DOP350 is fitted out with a bracket at its top for easy hose handling

The size of the DOP was based on the estimated production capability of the downstream water treatment plant. The balance of dredge slurry production and effluent outflow from the engineered containment facility into the water treatment plant is of critical importance to the success of this project.

The project set up includes a pontoon based crane for handling the DOP dredge pump

The job at Randle Reef can be described best as a huge clean-up action. Hamilton Harbour is listed under the Canada and United States Great Lakes water quality agreement as an area of concern. Areas of concern are locations on the Great Lakes are where water quality and ecosystem health have been severally degraded by local development use or other activities. One of the last obstacles to restoring Hamilton Harbour and removing it from the list of areas of concern is the cleanup of contaminated sediments at Randle Reef located at the western end of Hamilton Harbour.

The DOP350 is fitted out with a leveler head which leaves a flat sea bed after dredging

Hamilton Harbour is the largest Canadian port on the great lakes and home to one of the largest concentrations of heavy industry in Canada including steel production. The contamination at Randle Reef is a result of multiple sources over a period of more than 150 years including coal gasification, petroleum refining, steel production, municipal waste, sewage effluent, and overland drainage.

The discharge piping of the DOP350 is being prepared

Randle Reef is contaminated with Polycyclic Aromatic Hydrocarbons (PAHs) and heavy metals. The PAHs are present in very high concentrations and are of greatest concern as because they are known to be persistent, toxic, and carcinogenic. PAHs contribute to restrictions on fish and wildlife consumption, fish and wildlife deformity, and reproductive problems in Hamilton Harbour.

The DOP350 ready for use at the environmental clean up

Cleaning up Randle Reef is one of the last vital steps remaining to remediate Hamilton Harbour. The project will reduce the amount and spread of contaminants through the Harbour, significantly improving water quality and fish and wildlife habitat. The Harbour will also experience economic and social benefits: improved shipping and port facilities, increased recreational opportunities and the promotion of the Harbour community as a clean and progressive place to live and work.

Inside the casing of the submersible pump the revolution counter is mounted safely