20 February 2019
Significant changes will be made to the cavern underneath Fort Regent to limit the number of times it has to be cleaned.
The cavern acts as a storage tank for overflows of sewage and water from the main sewerage system during storms. Keeping the overflows in the cavern prevents them from spilling onto St Aubin’s Bay. Once a storm has passed, the contents of the cavern are pumped to Bellozanne sewage treatment plant for processing.
The cavern, which can hold approximately 25,000 cubic metres of waste, is used roughly 80 times a year and cleaned annually. It takes an average of six workers, working ten to 12-hour shifts, between three to four weeks to clean the space. The task is not only lengthy but hazardous because of the nature of the sewage solids and grit left behind. Additionally, the main tank is a confined space with associated risks from gases, low oxygen and restricted, steep access.
Proposed modifications to the cavern will cost £533,587 and will create an automated cleaning system so that workers will not have to clean the space as frequently. Changes to pipes and pumps will also mean that waste is mixed and solids do not settle on the floor, so there will be fewer, if any, blockages.
Work is planned to start in May after the regular cleaning of the cavern has been completed.
The Minister for Infrastructure, Deputy Kevin Lewis, said: “This is an important upgrade to a critical piece of infrastructure that will significantly improve the operation of the cavern and reduce onerous maintenance requirements for Growth, Housing and Environment personnel.”