With hydraulic dredging set to start in the Port Hope Harbour this summer, passersby may notice a few additions to the Centre Pier. Containment equalization tanks, dewatering tubes and a water treatment plant were installed to facilitate the dredging process.
As part of the set up on the pier, five dewatering cells were also constructed with enough space to house 12-15 of the sediment dewatering tubes also called geosynthetic containment tubes. The contaminated sediment at the bottom of the harbour will be hydraulically dredged and pumped through a floating pipeline into the containment tubes. Chemicals are added to the dredged material prior to entering the containment tubes to aid coagulation and turn the slushy sediment into more solid materials for transportation to the waste management facility for long-term storage. Measuring between 35m and 44m, each tube is twice as long as a cricket pitch and half the height of the Statue of Liberty. When filled, a tube may be as tall as 2-2.4 metres. Each of the five dewatering cells is expected to hold three containment/dewatering tubes at a time.
Once full, a containment tube may take up to two weeks to fully dewater. Water removed from the tubes is directed towards the containment equalization tanks before being treated by the onsite water treatment plant. The treated water is then pumped back into the harbour.
This PHAI site is very visible in the community as work is taking place amidst the busy Port Hope waterfront where anglers can be seen every day of the year and beaches are enjoyed by both our residents and tourists alike. As a vibrant, active community, the completion of the cleanup in this area of town has been long-anticipated.
The Port Hope Harbour is one of the largest components of the PHAI work under the Port Hope Project with contaminated sediment to be removed and transported to the Port Hope Long-Term Waste Management Facility (LTWMF) for storage. Mechanical dredging began in 2019 with the removal of a few large items such as a vehicle or two! The project team is now set to move to the next phase of dredging – hydraulic. Rumours have it that there are many, many pairs of sunglasses and even a television from when the Blue Jays won the World Series to be found.
Once the cleanup of the Port Hope Harbour is complete, the expectation is that the site will be removed from the Great Lakes Areas of Concern. Additionally, the harbour will undergo habitat restoration.
The PHAI provides a solution to this long-standing environmental problem that allows for the creation of a cleaner environment for generations to come. For more information on the Port Hope Projects, contact us at 905.885.0291 or [email protected].