The hot summer season came and went this year, without the problems over water supply that we experienced in previous years. Last year, we may recall, the people in the east zone of Metro Manila suffered water rationing, with people lining up with their pails and barrels as government opened major water outlets in the streets in the area.

That was described as the worst water crisis in Metro Manila in nearly a decade. And it was due, officials and the private concessionaires said, to the lack of summer rains, rising demand, and infrastructure delays.

Because of lack of rain, due in part to El Niño, the water levels were down in Angat Dam and La Mesa Dam. There was also delay in the construction of new water supply infrastructures. President Duterte warned the two private concessionaires he would have their contracts with the government reviewed. After the presidential warning, the water supply somehow improved.

There was no water problem in Metro Manila this summer and the rains have already begun. This week, the Metropolitan Waterworks and Sewerage System (MWSS) disclosed that one other reason there was no problem this year was the completion after four years of Tunnel 4 from Ipo Dam to barangay Bigte in Norzagaray, Bulacan, at a cost of P3.29 billion.

Tunnel 4 is 6.3 kilometers long with an internal diameter of four meters. From Bigte, the water flows on to La Mesa Dam via Aqueducts 1 and 2. A new aqueduct is now being planned to replace the old and dilapidated Aqueducts 1 and 2. With Tunnel 4 now in operation, other upstream tunnels may now be sequentially closed for inspection and rehabilitation.

Parts of the entire water supply system from Angat Dam are as old as 75 years, most likely now in poor condition, and not in compliance with new structural requirements against possible earthquake damage, MWSS Administrator Emmanuel Salamat said.

With the completion of Tunnel 4, the MWSS can now begin a long-delayed inspection of the entire system to see which need repairs and modernizing. But we have already seen its beneficent effects — because it provided additional water supply, there was no shortage, no long lines of empty pails and barrels in city streets, no water problem this summer.