The Sir John Compton Dam is surrounded by lush vegetation and looks to be filled with pristine waters. However, silt has been building up, especially since Hurricane Tomas in 2010 and a severe trough in December 2013, which both also contributed to heavy landslides in the Roseau reservoir and resulted in a reduced capacity of about thirty percent.
Though the technical process of the desiltation has begun, there is no set date as to when it will physically commence. Still it is something that needs to be done due to the amount of heavy siltation, especially after hurricane Tomas.
“One of our ports – we have two ports in the dam, a lower port and an upper port – extracts the water from the reservoir. The bottom one is actually blocked up with silt, therefore we’re using the upper port. That’s why during the dry season, as the levels are dropping, we have to now start rationing water because we don’t have access to the lower port,” Senior Supervisor Water Services, Timothy James, told the STAR when we visited the dam this week.
James said the desiltation process could take a period of five years to complete once they have a start date. He also noted that in order to find a suitable technical method, WASCO had to consider how it would be done without disrupting water supply and quality. He remarked that while they’d found a way around the issue, it was now a matter of sourcing the right contractors and cost.
James elaborated on the cause of the excess siltation in the dam: “Our pumps were destroyed after Tomas, and that’s where the heavy siltation came from. And actually, we were out of water supply for a month, and so we had to use other sources [of water] like Ravine Poisson and Vanard.”
Speaking on issues that arise during the drought season, James noted that WASCO usually implements a water-rationing schedule so that resources won’t deplete rapidly. He said the drought season was usually “a bad period of a three-month dry spell”.
“That’s why we have other supply sources whereby we reduce the amount of water we take from the dam,” he said. “We normally extract on average 7.1 million gallons a day from the dam.”
Contrary to public perception, James said the island has not yet recorded any droughts for 2017, due to steady rainfall.
“Our level is just about two feet below the overflow level at this point. Normally around this time, we usually are in a water-rationed mode, about six feet below. So this year is really good.”
In his opinion the water conservation issue relies on the people. “They’re only more conscious of it when we’re in the dry period,” James said. “After that people get back to their merry ways. During the drought, that’s when everyone is more sensitive to water.”
On the contrary, there are a lot of areas in Saint Lucia that undergo issues with water consistency. This is not because of lack of supply from the dam but the location and structures of some areas. In the dry season a lot of the rural areas experience water problems whereas during the rainy season, typically, there aren’t as many issues.
“We have areas in Babonneau that sometimes we have to schedule the water for everybody because we have to upgrade our pipelines,” James said. He emphasised that those are things WASCO is working on, and they have in fact come a long way in the last few years.