Strain on drains
by Julia Rawlins-Bentham
The intensity of rainfall is taking a toll on Barbados’ drainage systems, which were not designed to handle the volumes currently being experienced.
But residents are being assured that the Drainage Division is doing all that it can to mitigate against flood waters which follow such events.
Topping the list of concerns for Director of the Drainage Division, Keith Barrow, this hurricane season, is the projection for increased rainfall events, their intensity and duration.
Barrow explained that the basic design for Barbados was a one in 25 year storm, or eight inches of rain within a 24-hour period. But, he said, the time span between events of recent was short and cumulative, resulting in flooding.
“Most of our drain structures were built several years ago and were not really designed for major events like we are witnessing now,” he said.
He added that the whole issue of climate change as is witnessed now was not taken into consideration when most of the drains were initially built. “Whether you believe in climate change as a phenomenon within itself, or whether you believe that the climate is always changing, evidence points to increased intensity, duration and frequency of extreme rainfall events,” Barrow said.
However, he noted that staff at the division continued to examine ways of reducing the effects of heavy rainfall in flood-prone areas.
“Having water on the ground beyond six hours is a concern to us,” he said.
Areas of concern in the south of the island include Dover; St. Lawrence, especially near the Graeme Hall Swamp, through the sluice gate; St. Lawrence Gap, Christ Church and Long Beach in St. Philip.
Barrow explained that Graeme Hall Swamp was a major concern to the division as the sluice gate was inoperable for some time. He added that to alleviate the build-up of water in the swamp, crews manually opened the gate.
Meanwhile, the division is also working with the Coastal Zone Management Unit and the Natural Heritage Department and their consultants to design and modify the existing gate, and to create an additional system to allow for the vetting of water from the swamp without opening the gate.
On the west coast, districts of concern are Sunset Crest leading through to the Holetown Police Station and the library complex, including Cherry Tree Avenue, and Trents Tenantry in St. James. The latter area was described as presenting authorities with a “perennial problem”.
Barrow explained that residents in that district had a severe problem where even moderate rainfall caused flooding. However, he disclosed that the division was looking to have consultants study the problem and propose alternate solutions so the best option could be selected.
However, the director pointed out that in the interim, the division would seek a short-term solution by going upstream in an attempt to stop water from approaching the Trents community.
Meanwhile, work is also being done in Seaview Road, St. James where storm water wells were installed. In addition, Barrow said crews from the Drainage Division cleaned the drains in preparation for the rainy season.
In Speightstown, St. Peter there is an ongoing development which is expected to alleviate flooding there, while the CZMU’s ongoing Holetown Waterfront Improvement project is expected to help with relieving flooding in the area.
Barrow added that the division was also receiving assistance with flood control from other agencies and programmes, and was liaising with the Limegrove Lifestyle Centre to control the flooding.
“Our main concern is to get upstream of the west coast. That is where we think we can intercept the storm water runoff,” he said.
The Drainage Division is also working with the Environmental Protection Department to analyse storm water runoff that reaches that coast to identify possible contaminants in the water which may affect the near shore environment.
However, he noted that extreme flooding in Woodbourne, Christ Church was not as a result of a drainage problem.
“The problems at Woodbourne are caused by the geology of the area,” he said, noting that the division still maintained a close eye on conditions there to ensure residents’ safety.
In addition, Operation Clean City, which concentrates on the City of Bridgetown and its main water artery, the Constitution River, is ongoing and has been intensified with crew members from the Drainage Division cleaning drains every Sunday.
Barrow added that the division’s preparations also extended to their emergency plan for response in extreme rain events being updated. Moreover, the division is in constant communication with the Department of Emergency Management and the Meteorological Office to receive early warning of extreme rain events.
But, the director has made it clear that while the Drainage Division was recording some successes they could not prevent flooding.
“Every day we do drainage work. At this time of year it is more intense. During the dry season we try to concentrate on adding new drainage structures or cleaning existing drainage structures,” Barrow said.
He added that two months ago the division acquired a combination tanker which allowed crew members to pump water from areas which were flooded and such debris from inside drains to assist with flooding.
However, while the Drainage Division is working to keep drains clear, Barrow is urging the public to keep around their homes and storm water structures clean.
He is also urging them to avoid throwing debris into the drains and blocking them.
“We have found everything except human bodies in the drains,” he said.
Barrow also made an appeal for residents to stop running their domestic water into drains.
“This is soap and laundry water. That type of water always affects the fissures in the storm water wells,” he pointed out, warning that the effects could be detrimental to the country. (BGIS)