Improvements to sewage plants outlined

The Government of Barbados will be pumping $210 million into a one-of-a-kind, large-scale water reclaim and reuse project on the south coast that’s expected to add close to 200,000 more gallons per day to this island’s scarce drinking water supply.

Technical Advisor to the state-owned Barbados Water Authority (BWA) Dr John Mwansa said on Thursday that the intention is to reclaim about 10 per cent of the 1.98 million gallons of potable water which is currently pumped through the system.

Speaking to Barbados TODAY following the presentation by two foreign experts of a pre-feasibility study and an Environmental and Social Impact Assessment (EIA) for the South Coast Reclamation Project at a virtual town hall meeting on Wednesday evening,  Dr Mwansa disclosed that once funding for the project through a loan from China is in hand, construction work should start.

“We are still waiting on the loan approval. We have submitted the documentation for a loan application to the Chinese Exim Bank for the total amount. Once we get the loan, then the contractor will do the final design. What we have now is a conceptual design. The final design will be started and completed within a three-month period; and we will be ready to start,” the BWA Advisor revealed.

Boasting that Barbados would become the first country in the Caribbean to implement a project of this magnitude which reclaims ground water and reuses it for drinking purposes, Dr. Mwansa explained that while the BWA currently pumps about 1.9 million gallons of water through its system per day, the country would only get to benefit from 1.7 million gallons because the rest is lost when the commodity is recycled.

The technical consultant said: “We are basically looking to upgrade both plants…Bridgetown and South Coast [Sewage Plants] and reclaim that for water reuse. That is to be about 10 per cent of the amount that we pump on a daily basis for potable water. So if for example, you said that that water which is currently being used for potable water is being used for irrigation, that would free up that amount…10 per cent would become a variable to remain to be used for potable water usage rather than non-potable water usage.”

At the town hall meeting, when  Matt McTaggart, Project Manager for the company, Architecture, Engineering, Consulting, Operations, and Maintenance (AECOM) presented the pre-feasibility study for the South Coast Water Reclamation project, he disclosed that the existing sewage treatment plant at Graeme Hall, Christ Church would be upgraded to include a special facility with new equipment to remove rags, grit, sand and other debris from the sewage system.

Stating that this facility will comprise a mechanism to control odour from the sewage, McTaggart also disclosed that a new secondary station will be built to take the effluent from one building and transfer it to a new and more advanced treatment plant nearby.

These form part of a series of structures to be built in the same compound as the existing sewage treatment plant to be known as the South Coast Water Resource Recovery Facility.

“You will have secondary treatment, which is more than secondary treatment…it’s a biological nutrient removal plant which also is for removing nitrogen and phosphorus. This will be sized for 18,000 cubic meters [3.9 million gallons of waste water] per day,” the consultant told the virtual meeting.

He said the average amount of waste water that is estimated to flow through the facility designed to remove foreign material would be two million gallons per day.

The hydrology expert also said a structure will be built to redirect the treated waste water that is more than 3.9 million gallons, into the sea.

According to the pre-feasibility study presented by McTaggart, some of the other structures to be constructed as part of the South Coast Water Resource Recovery Facility include one for disinfecting, another for filtering waste water entering the plant and a third to store and pump the water extracted for drinking.

McTaggart said that ground water modelling was also done to determine the impact of replenishing the aquifer in Christ Church where the water that flows through that surface is not for drinking purposes.

He said this was undertaken against the backdrop of a new brackish water desalination treatment plant to be built by the Government south-west of the Grantley Adams International Airport and close to Gibbons Bogg.

“The proposed future ground water extracts for that plant are about 86 million imperial gallons per day. We wanted to use the modelling to optimize the non-potable recharge location to maximize the withdrawals of that water at the proposed extraction wells site; and also to consider the private irrigation wells that are in the Gibbons Boggs area,” he reported. emmanueljoseph@barbadostoday.bb