GEORGE TOWN: The Penang Water Supply Corporation (PBAPP) has issued an alert for water consumers in the state to use water wisely following a drop in the Air Itam Dam effective capacity and high water demand.
PBAPP chief executive officer Datuk Jaseni Maidinsa said that as of Thursday (March 31), the effective capacities of Penang's three key dams were 38.5 per cent for the Air Itam Dam, Teluk Bahang Dam (73.5 per cent) and Mengkuang Dam (91.4 per cent).
He said that since Jan 1, this year, the effective capacity of the Air Itam Dam had dropped by 50.8 per cent to an "alert level" of 38.5 per cent.
"The primary cause is low rainfall in this dam's water catchment area (WCA).
"The secondary cause is high daily water demand in the Air Itam township and surrounding areas," he said, adding that in the period between Jan 1 and March 31, 2022, PBAPP recorded abnormally low rainfall amounting to 250mm of rainfall in the Air Itam Dam WCA.
In comparison, the amount of rainfall recorded in the Teluk Bahang Dam WCA was 366mm while the rainfall at the Mengkuang Dam WCA amounted to 1,128mm.
The only way to replenish the reserves of the Air Itam Dam is to wait for seasonal rainfall or to induce rainfall (via cloud seeding) in its WCA.
PBAPP, Jaseni said, had also been recording consistently high water consumption in the state over the past three months while striving to implement dry weather controls to "defend" the effective capacities of Penang's dams.
He said that on March 31, this year, the metered water consumption was almost 900 million litres per day (MLD), as compared to the average of 860 MLD in 2021.
He added that treated water pumped from the Sungai Dua Water Treatment Plant (WTP) in Seberang Prai to the Bukit Dumbar Reservoirs on Penang island daily (via three sets of twin submarine pipelines) was being drawn down fast.
"Water demand in the southern areas of Penang island is significantly high. As such, the treated water levels in the Bukit Dumbar reservoirs are low.
"Since the treated water levels are low, PBAPP cannot pump water at adequate pressures to all end-of-line (EOL) and higher ground areas.
"The water pumps will trip or shut down automatically and may be damaged," he said.
According to Jaseni, PBAPP is implementing various short-term solutions to address complaints of "no water supply" or "low water pressure" in several areas in Seberang Prai Selatan (SPS), in the Air Itam hillside areas and at a few blocks of 5-storey apartments at Bukit Gedung.
These solutions include:
• Ramping up treated water production at all nine water treatments plants in Penang to meet daily high water demand;
• Increasing treated water production at the Air Itam WTP, Guillemard WTP and Batu Ferringhi WTP to support a gradual build-up of treated water reserves in the Bukit Dumbar reservoirs;
• At Bukit Gedung, PBAPP has installed taps at fire hydrants to provide water supply to the residents of affected apartment blocks. Due to low water pressure, water supply can now only reach the ground floor and first floor of several apartment blocks; and,
• Advising building management corporations (including the management corporation of the Bukit Gedung apartments) to install residential pumping systems at EOL or higher ground areas to mitigate issues of low water pressure during dry seasons.
"The long-term solution to water supply issues in the EOL and higher ground areas in SPS, Air Itam and Bukit Gedong is the timely implementation of PBAPP's Raw Water Contingency Plan 2030 (RWCP 2030).
"The targeted yield of the RWCP 2030 projects is 569 MLD, and the availability of this additional volume of water should help to minimise water issues throughout Penang during future dry seasons.
"For now, water consumers are advised to use water wisely until the inter-monsoon season in April/May brings rainfall to the dam WCAs," he added.