Metro Manila (CNN Philippines, March 14) — Senate President Vicente "Tito" Sotto III sees removing salt from seawater as a solution to Metro Manila's present water woes.

"Mag-desalination plant na tayo. Bakit ang Saudi Arabia, ang mga Middle East countries ang lakas ng tubig? Napakaraming tubig … Kasi nag-desalinate sila," Sotto told CNN Philippines' The Source on Thursday.

[Translation: Let's have a desalination plant. Why does Saudi Arabia and Middle East countries have lots of water? It's because they desalinated.]

Sotto added that there should not be qualms about the cost of water desalination.

"Mas marami tayong pinagkakagastusan na kung anu-anong kabulastugan," he said.

[Translation: We're spending a lot on many nonsensical things.]

In a text message to CNN Philippines, Sotto said a desalination plant that would serve around 300,000 people previously cost around $100 million.

But he added, "The cost of putting up a plant has gone down tremendously over the past decade."

Manila Water Communications Manager Dittie Galang told CNN Philippines in a text message that using desalination in the country would be "very costly" and will raise tariffs, or water rates.

"Treatment of water is part of the operations expense of a water utility company. If desalination is used, the cost will be part of the operations expense and may be part of the computation of the tariff," Galang said.

However, the project did not push through as the local water service provider could not afford taxes and the cost of acquiring lands for the proposed facilities.

West zone water concessionaire Maynilad also sought for a feasibility study into the construction of a desalination plant using Manila Bay as a water source in 2015 and 2018, but it is unclear whether they have received such studies.

Sotto said he had long been calling for the country to tap into its vast sea resources through desalination. Presently, Metro Manila relies heavily on Angat and La Mesa dams for its water supply.

Several countries, especially in arid areas like the Middle East, rely on desalination for potable water. Desalination is a process by which salt is removed from seawater for it to be potable.

In 2010, the Japan International Cooperation Agency proposed an approximately ₱2 billion water desalination plant in Cebu province to service Lapu, Lapu City in Mactan Island.

Parts of Metro Manila have experienced water interruptions in the past week, which east zone concessionaire Manila Water attributed to lower water levels in La Mesa Dam due to El Niño or a pattern of scarce rainfall. Recent Manila Water advisories said scheduled water interruptions could last until the end of the summer season.

But the Metropolitan Waterworks and Sewerage System, the government agency that oversees water supply in Metro Manila, said the decline of water supply in La Mesa Dam was caused by the increase in water treatment production of Manila Water.

LOOK: Angat Dam water level normal

The Senate will start a probe on the water shortage in Metro Manila next Tuesday.

CNN Philippines Multi-platform Writer Xave Gregorio contributed to this report.