Salalah, June 12 – Advance planning and an ‘Emergency Outflow Plan’ played a big role in saving Salalah from a disaster during the tropical storm Mekunu. The Salalah Sanitary Drainage Services Company (SSDC) managed to drain a huge amount of water during and after the landfall of the cyclone.
In an interview with Observer, Ghali al Mashali, CEO of SSDC, said: “In normal circumstances, the wastewater network handles an average flow of 40,000 to 45,000 cubic metres of water per day. From May 25, when the cyclone struck, to May 26 night, the total volume of water discharged to sea was 400,000 cubic metres, which is eight times the normal.”
As an after-effect, some 200,000 cubic metres more water was released to the sea, he said. “Thus, a total of 600,000 cubic metres of storm water was released into the sea in a span of 84 hours.”
The data is alarming and forces us to visualise the situation if SSDC’s ‘Emergency Outflow Plan’ was not in place. The project was conceptualised in the third quarter of 2015.
According to Al Mashali, the wastewater network played a significant role during the cyclone. “All the low lying areas which were flooded due to the storm water were dealt through wastewater collection and conveyance system.”
SSDC emergency team, said Al Mashali, responded to such an “unusual event” through “systematic and continuous management”, pumping excess storm water first from ‘area pumping stations’ to ‘main pumping stations’ and then to the sea through emergency outflow.
The team was successful in handling severe storm water flow without overflow/flooding in the area pumping stations or backflow to residential houses.
Due to continuous pumping of storm water, excess flooding of low lying areas was averted, thus limiting the damage to residents’ household items.
Wastewater was collected from different areas across the length and breadth of Salalah and other nearby districts through the network to area pumping stations.
In normal situations, wastewater is collected from different areas across Salalah and other nearby districts through a network of ‘area pumping stations’. The accumulated water goes to the ‘main pumping stations’ and finally to the water reclamation
After necessary tertiary treatment at the water reclamation plant, treated sewage effluent is reused for landscaping, construction works and industrial uses. The average daily flow to water reclamation plant is 40,000 to 45,000 cubic metres per day.
In emergency situations, wastewater is collected from different areas through the same ‘area’ and ‘main’ pumping station network and finally discharged in emergency outfall to the sea.
On lessons learnt from the cyclone, Al Mashali said: “The most important lesson is to have a ‘proper storm water system’ for the entire Salalah city and adjacent districts to avoid flooding in city areas and minimising the possibility of storm water entering into the waste water network.”