Award-winning water treatment plant upgrade seen as a model for industry


How do you keep a water treatment plant operating while decarbonising it, improving its resilience and expanding its capacity to cope with dramatic local changes?  

Since it was built in the 1980s, La Mesa Treatment Plant 1 (LMTP1) in the Philippines has faced significant changes to its operations. The catchment area it serves has grown dramatically as Metro Manila has developed, and as rainfall patterns in the region have changed over time.  

Built to treat 1500 million litres of water per day, improvements became necessary to accommodate increasing ranges of incoming water quality and improved resilience as local understanding of earthquake risk has improved. The plant had come to experience peaks regularly reaching ten times the average levels it was designed for and its ability to take the strain and treat water successful was under pressure. The upgrading of the plant has just won the Contracts Project of the Year award in the FIDIC Contract Users’ Awards announced this week.

What is the La Mesa Water Treatment Plant 1 (LMTP1) upgrade?

The sedimentation basins at LMTP1 have upgraded through the installation of tube settlers and sludge scrapers, which improved the plant’s capacity to treat higher levels of turbidity in raw water. This has proved crucial to sustaining normal water production despite varying raw water quality from Angat and Ipo Dams, particularly during the rainy season.

At the same time, the project installed a 1-megawatt photovoltaic solar farm, one of two that its owner Maynilad built within the La Mesa Compound. This new solar farm will augment the plant’s power requirements along with several other pumping stations, reducing the electricity consumption of Maynilad’s La Mesa facilities by around 90,000 kWh, as well as reducing carbon emissions by 21 tons per month.

Importantly, all of this was done alongside standard operation of the said treatment plant so that the population in the region continued to be served.

Embracing complexity and collaboration

The project involved upgrading twelve operating sedimentation basins and twenty-four operating gravity filters. In addition, there were upgrades made to overall electrical and control systems. This made for a complex timetable of handovers, staged takeovers and new works across the whole plant.

To ensure that went as smoothly as possible, the project team adopted international FIDIC contracts, engaged in extensive risk assessment of operating conditions and both owners and engineers then led implementation collaboratively.

Even as the pandemic took its toll, this collaborative approach to ensure that issues regarding the contractual and commercial side of the project, were well managed and saw all claims and variations as well as valuations reviewed and finalised in due time even during the pandemic, avoiding significant breakdowns in relationships.

As an illustration of how vital infrastructure can be dramatically upgraded, made more resilient and lower carbon while remaining operational even in very testing conditions that success is one the infrastructure sector can learn from.

In their citation for the project’s success in the FIDIC Contract Users’ Awards, the judges said that they were impressed by a project where the client was looking to improve a water treatment plant to accommodate increasing ranges of incoming water quality and also so improve resilience to handle potential earthquake related impacts.

Claims and variations were finalised in a timely fashion, said the judges, even during the challenging period of the pandemic, and there were strong sustainability measures, including solar panels to generate renewable energy. The good work of the engineer and also the contractor were also highlighted.  

The successful design and construction of La Mesa Water Treatment Plant 1 (LMTP1) in the Philippines has been judged by a panel of FIDIC experts as the FIDIC Contracts Project of the Year for 2022. It was nominated by Robinson Salenga, MPM, FIDIC Certified Consulting Practitioner FCCP, Project Manager of Maynilad Water Services Inc.