Presentation by Mr. Miguel Fernando B Umali and Mr Mark Calleja (Manila Water, Philippines) at the Seminar Cutting Edge Hydro Software for South-East Asia, during the Deltares Software Days South-East Asia 2018. Thursday, 6 September 2018, Yogyakarta.

1. Laguna Lake: A
Hydro-dynamic
and Water Quality
Study for Potential
Water Source for
Metro Manila
Miguel Umali
Mark Calleja
Manila Water Company, Inc.

2. Philippines
• Metro Manila
• Boracay
• Laguna
• Clark
• Cebu
• Zamboanga
Vietnam
Myanmar
Thailand
Indonesia

3. Manila Concession

4. to, now, more than
6,600,000 people
Since1997,
Has been providing
Water, Wastewater and
Environmental Services
Has been providing
Manila Water
Company
Manila Concession

5. Manila Concession
Complete
Water Value
Chain
Water Source
Water Treatment
Water Distribution
Sewer Collection
and Treatment
Customer
Relationship
Management

6. Manila Concession
“Our mission is to create an exceptional customer experience in the
provision of sustainable solutions vital to health and life.”

7. Outline
• Manila Concession Water Supply and Demand
• Laguna Lake as Potential Water Source
• Risks in drawing water from Laguna Lake
• Historical occurrence – salinity intrusion
• How do we plan to mitigate against these risks?
• Hydrodynamics of Laguna Lake
• Current undertakings and next steps

8. Demand and
Supply Gap
• Rapid development in Metro
Manila challenges Manila
Concession in providing
continuous and reliable water
supply 24/7
• Without exploring new water
sources, a supply gap is
imminent.

9. -
500
1,000
1,500
2,000
2,500
3,000
3,500
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037
MDD Demand (ADD) Available Supply + New Water Source Current Water Source
• New water sources are needed to augment the supply from Angat due
to the continuous increase in water demand in the East Zone.
2016 Supply
deficit during
MDD
Demand vs Supply – Manila Water Concession

10. -
500
1,000
1,500
2,000
2,500
3,000
3,500
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037
MDD Demand (ADD) Available Supply + New Water Source Current Water Source
• Even with the supply of the Central Bay, there is still an impending
supply deficit at 2022 until the new water source, Kaliwa arrives in
2023.
Kaliwa
300MLD
in 2023
Laiban
900MLD
in 2027Laguna Lake
Central Bay
100MLD in
2018 2022 Supply
deficit
Demand vs Supply – Manila Water Concession

11. -
500
1,000
1,500
2,000
2,500
3,000
3,500
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037
MDD Demand (ADD) Available Supply + New Water Source Current Water Source
• Due to this, the Laguna Lake East Bay Water Source is proposed as a
medium-term water supply source for the East Zone.
2022 Supply
deficit
Kaliwa
300MLD
in 2023
Laiban
900MLD
in 2027Laguna Lake
Central Bay
100MLD in
2018
Laguna Lake
East Bay
250MLD in
2022
Demand vs Supply – Manila Water Concession

12. Laguna Lake
Water Source
• Laguna Lake is a
potential water source
for the Manila
Concession
• Surface Area – 914 km²
• Average Depth – 2.5 m
• Perennially Turbid
• Competing use factors
• Fresh water for people
• Brackish water from fisheries
• Repository for Industry

13. Laguna Lake
Water Source
• With the support of
Deltares, Manila Water
identified the
Hydrodynamics and
Water Quality of Laguna
Lake
• In October 2017, Manila
Water requested
consultancy works from
Deltares, to study the
Laguna Lake Water
Source
• Fresh water for people

14. Rudy Schueder
• M.A.Sc. Civil Engineering (Canada)
• Consultant – Environmental hydrodynamics, Deltares (Netherlands)
• Specialist in numerical modelling of water quality in coastal systems
• Hydrodynamics and salinity intrusion in rivers
• Aquatic chemistry in reservoirs and estuaries
• Large scale emission modelling
• Working with Manila water on Laguna Lake since October 2017

15. Components considered in this study that
affects water quality
• Hydro-dynamics and Water Quality
• Water level of the lake
• Salinity
• Total Dissolved Solids (TDS)

16. Risks to drinking water in Laguna Lake – Water
volume considerations

17. Backflow Example (Baseline)

18. Historical occurrence – salinity intrusion

19. Historical occurrence – salinity intrusion – monthly average

20. Questions that arise from the data
• When will this salinity intrusion occur?
• When will it reach Central Bay and East Bay?
• How will these conditions change in the future?
• Some risks that MWCI foresees:
• El Nino?
• Typhoons?
• La Nina?
• Population and land use changes?

21. How do we plan to mitigate against these risks?
• Improve Water Supply Planning
to be prepared for:
• Salt Water Intrusion to the
lake
• El Nino
• Decrease in Water Quality
• Use Data Driven Design
• Better estimation of facility
cost
• Better estimate of
operating conditions of our
facilities
• Scenario Assessment of the
Lake

22. Hydro-dynamic Analysis of Laguna Lake
• Hydrodynamic & Water Quality modelling
• Scenario Selection
• Scenario Assessment
• Final Report and Model improvements

23. Hydrodynamic and water quality modelling
Delft3D
FLOW

24. Delft3D-FLOW model

25. Model Results

26. Scenario selection
The following 6 were identified as priority:
• The El Nino period between March 1997 and May 1998
(a dry period)
• Typhoon Ketsana in 2009
• Monsoon (wet year) in 2012
• Effect of reverse osmosis process used in water treatment
plants
• Sea level rise based on pessimistic predictions (+0.25 m)
• Southern and eastern population pressure increase

27. Creating an el Nino
• Used data from el Nino 1997-1998
• Rainfall will affect hydrological model: river flow rates will decrease
• Will affect hydrodynamic model: less water will enter the lake
(fluvial and pluvial) and lake level will drop
• Will affect water quality: more salinity will enter the lake

28. (Preliminary) Scenario assessment – el Nino
1997-1998
Tropical storm Bining
Typhoon Miling + Tropical Storm Cass

29. (Preliminary) Scenario assessment – el Nino
1997-1998

30. (Preliminary) Scenario assessment – el Nino
1997-1998

31. Backflow Example (El Nino)

32. • Updating the Base Model to the
current data given by the
agency covering Laguna Lake
• Applying the models on other
watershed (such as La Mesa
Watershed)
• Training and improvement of
the team in relations to
Modelling, and calibrations
Current Undertakings

33. Team Members
Miguel Umali
SAM-SAPD
Anjelica Ancheta
SAM-WREP
Mark Calleja
SAM-SAPD
Hydrodynamics
Water Quality
Romulo Samia
SAM-SAPD
Louie Gugol
SAM-SAPD
Consultant - Deltares
Rudy Schueder
Deltares

34. Thank You!