DPWH report: Flood management master plan for Metro Manila and surrounding areas

 

Flood management master plan for Metro Manila and surrounding areas

(As of June 15, 2013)

Objective:

After the flood events brought about by typhoons Ondoy and Pepeng in September and October 2009, respectively, that caused severe damage in Metro Manila and surrounding areas, the World Bank has provided a technical grant in the amount of $1.5 million under the Global Facility for Disaster Reduction and Recovery Trust Fund of the Australian Agency for International Development (AusAID).

A flood risk assessment study for the entire Metro Manila and surrounding basin area was undertaken from February 2011 to February 2012, to prepare a comprehensive flood risk management plan for the same and to determine a set of priority structural measures, which will still undergo individual feasibility studies and detailed design prior to implementation, including nonstructural measures that will provide sustainable flood management up to a designated safety level and serve as the roadmap/vision of the government until 2035 (23 years from now).

Boundary of study area and the river basins:

DPWH-Flood-Management-Map1

The study area covers the entire Metro Manila and the surrounding areas, particularly, provinces of Rizal, Laguna, and parts of Bulacan, with a total area of 4,354 sq. km or 435,400 hectares, which is seven times the size of Metro Manila and two-thirds that of Singapore.

It also encompasses the Pasig-Marikina River Basin, Malabon-Tullahan, Meycauayan, South Parañaque-Las Piñas, and the Laguna Lake Basins, including drainage basins. Administration Areas in and around the study area include 16 cities and one municipality in the National Capital Region (NCR), 63 cities/municipalities in the CALABARZON area and eight cities/municipalities in Bulacan with a population of 20,433,722 in and around the Study Area and estimated population of 17,147,658 in the study area.

Guiding principles for master plan development:

1. Adopt the principles of integrated water resources management and river basin approach
2. Develop a safe society with resiliency to floods through:

  • Structural measures for the river basins and waterways
  • Structural measures for the Laguna lakeshore, and
  • Improvement of the urban drainage system

3. Improvement of the Flood Information and Warning System (FIWS)
4. Establish an integrated and consistent flood risk management (FRM) institutional system
5. Strengthen community-based flood risk management—land use and solid waste
6. Utilization of runoff waters as water resources, etc.
7. Reforestation and watershed management

Three major flooding occurrences:

1. Huge volume of water coming from Sierra Madre
2. Drainage capacity constraints in core area of Metro Manila
3. Low-lying communities around Manila Bay and Laguna Lake

DPWH-Flood-Management-Map2

DPWH-Flood-Management-Map3

The diagram showed the Master Plan’s optimum recommendations for structural measures in combination with nonstructural measures for the Pasig-Marikina River Basin and adjacent areas. In order to reduce the peak discharge of inflow equivalent to 3,600 m3/s under a 100-year return period from flowing downstream, a dam is proposed to be constructed in the upstream portion of Upper-Upper Marikina River in Rodriguez, Rizal (Montalban) so that only 900 m3/s discharge of outflow will go down. To further reduce the peak discharge of 900 m3/s from flowing down the Upper-Upper Marikina River, the area between the Tumana Bridge and the San Mateo Bridge, and the area upstream of the San Mateo Bridge, with a combined total length of 4.0 km and maximum width of 1.5 km will be utilized as a natural retarding basin by constructing small dikes beside natural levees alongside river area management and flood plain management.

In addition to the above, river improvements such as a combination of dike/river wall construction and excavation, dredging/excavation only, or river wall construction only will be carried out at different locations, as applicable, along the Pasig and Marikina Rivers and adjacent areas including river area management and flood plain management when needed, to ensure that the target safety level for mitigation measures will be achieved.

For the other river basins, except Laguna Lake Basin, river improvements combined with river area management and flood plain management were recommended to ensure that the target safety level for mitigation measures for each will be achieved.

Project impact:

Screen Shot 2013-06-19 at 2.34.56 PM

An estimated 1.6 million people will directly benefit from the mitigating structural measures for the Pasig-Marikina River Basin and adjacent areas and around P43 billion will be saved from direct damages due to floods.

Proposed components and measures under the drainage improvement in the core area of Metropolitan Manila (DICAMM)

DPWH-Flood-Management-Map4

1. Rehabilitation of 15 Major Pumping Stations
2. Rehabilitation of Drainage Channel

    • Removal of Obstructions within drainage channels with settlements
    • Dredging and Declogging
    • Rehabilitation of Drainage Mains

3. Additional Drainage Mains/Box culverts

 

Laguna Lakeshore:

DPWH-Flood-Management-Map5

The following are the optimum solutions in solving the flooding situation in the Laguna lakeshore area:

1. Putting up a road dike around the lake with pumping stations
2. Lakeshore land raising with road and future developments
3. Construction of a spillway that will cut through the heavily built-up Parañaque City and another one that will go through to the Pacific Ocean
4. Dredging works
5. River improvements for the selected inflow rivers of the lake developments

Structural mitigation measures:

There are 11 recommended shortlisted structural mitigation measures under the “Flood Management Master Plan for Metro Manila and Surrounding Areas” that will serve as the roadmap of the government, which is envisioned to be implemented from today until 2035 (23 years).

These projects were prioritized according to: (1) the severity of floods based on flood risk, flood area, duration of floods and flood damage, (2) technical viability, (3) social and environmental viability in preliminary level, and (4) aerial distribution of putting priority for the flood mitigation measures for the rivers and Laguna Lake.

Hereunder are the 11 long-term projects with an estimated cost of around P351.72 billion. However, the following are still subject to validation of individual projects via a comprehensive feasibility study and detailed design that can either be financed using government funds or requested under official development assistance.

Name of Project

Est. Cost (P’B)

Pasig-Marikina River Improvement and Dam Construction

198.435 B

Meycauayan River Improvement

14.040 B

Malabon-Tullahan River Improvement
 

21.635 B

South Parañaque-Las Piñas River Improvement

17.335B

East Mangahan Floodway (Cainta & Taytay River Improvement)

25.901 B

West Laguna Lakeshore Land Raising

25.185B

Land Raising for Small Cities around Laguna Lakeshore

7.158 B

Improvement of the Inflow Rivers to Laguna Lake

0.637 B

 Manila Core Area Drainage Improvement

27.257 B

West Mangahan Area Drainage Improvement

5.522 B

Valenzuela-Obando-Meycauayan (VOM) Improvement (to be studied further)

8.613 B

      Total:

 P 351.718 B

 

Each of the above projects is independent, but they form integral measures for mitigating floods in Metro Manila and surrounding areas. Hence, considering the need for immediate interventions to ease the flooding problems in these areas, several high-impact flood control projects amounting to P5 billion were identified for immediate implementation, to wit:

Name of Project

Total Cost

Released Amount

SARO No.

National Capital Region (NCR):
Valenzuela-Obando-Meycauayan (VOM) Project

820.0 M

820.0 M

A-12-01110

dated 11/22/12

A-12-01111

dated 11/22/12

A-12-01112

dated 11/22/12

A-13-00684

dated 03/14/13

KAMANAVA Project, Phase I (Kalookan-Malabon-Navotas Area)

700.0 M

380.0 M

A-12-01111

dated 11/22/12

A-12-01112

dated 11/22/12

Manila Bay Seawall Project

700.6 M

211.0 M

A-12-01125

dated 11/23/12

A-13-00684

dated 03/14/13

Upper Marikina River Improvement Project (Nangka River)

222.5 M

222.5 M

A-12-01112

dated 11/22/12

A-12-01113

dated 11/22/12

Marikina River Dredging

50.0 M

50.0 M

A-13-00684

dated 03/14/13

Mangahan Floodway Dredging

100.0 M

100.0 M

A-12-01111

dated 11/22/12

A-12-01112

dated 11/22/12

West Side of Mangahan Floodway Project

250.0 M

East Side of Mangahan Floodway Project

190.0 M

190.0 M

A-12-01112

dated 11/22/12

Additional Projects

50.9 M

50.9 M

A-12-01112

dated 11/22/12

A-13-00117

dated 01/15/13

Region III:
Dredging of Labangan Channel, Hagonoy, Bulacan

100.0 M

100.0 M

A-12-01113

dated 11/22/12

San Fernando-Sto. Tomas-Minalin Tail Dike

139.0 M

139.0 M

A-13-00684

dated 03/14/13

Mitigation Measures for Breaches in the San Fernando-Sto. Tomas-Minalin Tail Dike

637.0 M

637.0 M

A-13-00684

dated 03/14/13

Del Carmen-Balimbing Creek, City of San Fernando, Pampanga

30.0 M

30.0 M

A-12-01112

dated 11/22/12

Orani Channel, Bataan

50.0 M

50.0 M

A-12-01125

dated 11/23/12

Region IV-A:
Sta. Maria-Mabitac River

400.0 M

400.0 M

A-13-00141

dated 01/15/13

Sta. Cruz River

180.0 M

180.0 M

A-13-00141

dated 01/15/13

San Pedro River

100.0 M

100.0 M

A-13-00141

dated 01/15/13

Biñan River

100.0 M

100.0 M

A-13-00141

dated 01/15/13

Nationwide:
Various Dredging Equipment

136.5 M

136.5 M

A-12-01111

dated 11/22/12

Operation and Maintenance of Dredging Equipment for Pasac-Delta Waterway, Guagua and Sasmuan, Pampanga

43.5 M

43.5 M

A-12-01111

dated 11/22/12

Grand Total:

5,000.0 M

3,940.4 M

 

 

Out of the P5 billion, P3.940 billion was already released for various flood-control projects. The detailed list of the high impact flood control projects with the corresponding status is tabulated below.

In addition to the above, the rehabilitation/improvement of 12 existing pumping stations in Metro Manila amounting to P1.600 billion was likewise approved and released to the MMDA.

Clearing of eight major waterways in Metro Manila with an estimated 20,000 informal settlers that will be provided decent resettlements is also part of an interagency efforts being undertaken by the government.

Nonstructural measures:

 1. Strengthening of the Flood Information and Warning System (FIWS)

    • Effective Flood Control Operation and Warning System (EFCOS) improvement
    • New telemetric rainfall and water level gauging stations

2.Capacity building for strengthening community-based flood risk management

    • Update and implement Information and Education Campaign (IEC) programs
    • Rainfall and water level  monitoring by barangay disaster risk reduction and management councils (BDRRMCs)
    • Construction of evacuation routes and temporary evacuation centers

3. Improvement of the Management Information System (MIS) for Disaster Risk Management

    • Improvement and development of MIS
    • Capacity building

4. Reforestation and Watershed Management

 

Status of P5 billion high-impact flood control projects:

Name of Project

Total Cost

(Mil. Peso)

Released Amount

(Mil. Peso)

Status/Remarks

National Capital Region (NCR):
  1. Valenzuela-Obando-Meycauayan (VOM) Project

 

Description:

Raising and/or construction of flood control wall along Meycauayan River and Palasan River including repair/rehabilitation of damaged existing dike along Palasan River.

 

<>Additional projects are necessary to sustain the initial interventions currently being implemented to further contribute in the mitigation of the perennial flooding in the area, as follows:

 

A.) Construction of Flood Control Wall along Palasan River in Obando, Bulacan (Closure of Gaps), Length – 4.97 km

 

B.) Construction of Pumping Station and Flood Gates at Polo River in Brgy. Wawang Pulo, Valenzuela City

 

(Please see “Annex A” for additional details/explanations)

 

820.0

820.0

<>22 out of the 22 projects have already budget releases amounting to P820.0 M.<>13 of the 22 projects have started January 2013  with an average accomplishment of 28.20% (with 1 project already completed), 8 projects were already bid-out and just started 20 May 2013 while the remaining project will be for bidding this year.<>Funds for the additional projects is proposed to be taken from other projects herein that are not yet implemented since it will entail further study in addition to any available budget of the Department.
  1. KAMANAVA Project, Phase I (Kalookan-Malabon-Navotas Area)

 

Description:

Drainage rehabilitation of Catmon Creek, rehabilitation of riverwall along Malabon-Tullahan river and construction of pumping stations and floodgates.

 

<>The remaining 3 projects are as follows:

 

A.) Construction of Floodgates at Chungkang River, Brgy. Dampalit, Malabon City (P20.0 M)

 

– Funds to be requested.

 

B.) Construction of Breakwater at Manila Bay Facing Navotas River (Navotas Navigation Gate) (P100.0 M)

 

– Since this will entail further study by the BOD-In-House Consultant, which is yet to be conducted prior to implementation, it is deemed that funds allocated for this be realigned to the additional projects being proposed for the VOM Project.

 

C.) Construction of Pumping Station at Longos (P200.0 M)

 

– It is requested by the LGU that funds be realigned instead to the Rehabilitation of Pumping Station (PS) and Flood Gate (FG) (from Tañong to PNR Bridge) and Raising of Riverwalls (from PNR Bridge to Mc Arthur Highway).

 

700.0

380.0

<>8 out of the 11 projects have already budget releases amounting to P380.0 M.<>6 of the 8 projects have started January and February 2013 with an average accomplishment of 37.10% (with 2 projects already completed), while the remaining 2 projects will be for bidding this year.<>The balance of P320.0 M for the remaining 3 projects will be requested within this year.
  1. Manila Bay Seawall Project

 

Description:

Strengthening of existing seawall, construction of floodgates (Remedios & Salas) & repair/rehabilitation of Luneta Pumping Station and construction of breakwater (subject for validation during detailed study).

 

<>The remaining 2 projects are as follows:

A.) Construction of Two (2) Floodgates (Remedios & Salas) (subject for validation during detailed study) & Repair/Rehabilitation of Luneta Pumping Station (P180.0 M)

 

– Since this will entail further study by the BOD-In-House Consultant, which is yet to be conducted prior to implementation, it is deemed that funds allocated for this be realigned to the additional projects being proposed for the VOM Project.

B.) Construction of Breakwater (36mx6mx5mx1km) @ Php 5,000/m3 (subject for validation during detailed study) (P309.548 M)

 

– Since this will entail further study, which is yet to be conducted prior to implementation, it is deemed that funds allocated for this be realigned to the additional projects being proposed for the VOM Project. Proposal to conduct study, preliminary engineering and Detailed Engineering Design was submitted to this Department by the UPNEC per letter dated 03 May 2013.

 

700.6

211.052

<>2 out of the 4 projects have already budget releases amounting to P211.052 M.<>1 of the 2 projects have already accomplished 99.10% while the other is yet to be started since funds for the same was just released on 14 March 2013.<>The balance of P489.548 M for the remaining 2 projects will be requested within this year.
  1. Upper Marikina River Improvement Project  (Nangka River)

 

Description:

Construction of reinforced concrete slope protection, parapet wall and/or gravity wall along Nangka River.

222.5

222.5

<>6 out of the 6 projects have already budget releases amounting to P222.5 M.<>4 of the 6 projects have started December 2012 and January 2013 with an average accomplishment of 77.30%, while the remaining 2 projects have just started.
  1. Marikina River Dredging

 

Description:

Dredging works

50.0

50.0

<>Funds for this project was just released last 14 March 2013 amounting to P50.0 M.<>The project was bid out last 19 March 2013 and has an accomplishment of 30%.
  1. Mangahan Floodway Dredging

 

Description:

Dredging works

100.0

100.0

<>2 out of the 2 projects have already budget releases amounting to P100.0 M.<>The projects have started January and February 2013 with an average accomplishment of 89%.
  1. West Side of Mangahan Floodway Project

 

<>Construction of Pumping Station at Ilugin River, Pasig City (4 pumps @ 3 cu.m./sec)  (P250.0 M)

 

– Since this will entail further study by the BOD-In-House Consultant, which is yet to be conducted prior to implementation, it is deemed that funds allocated for this be realigned to the additional projects being proposed for the VOM Project.

 

250.0

<>Funds for this project will be requested within this year.
  1. East Side of Mangahan Floodway Project

 

Description:

Construction of slope protection along Cainta and Taytay Rivers.

190.0

190.0

<>4 out of the 4 projects have already budget releases amounting to P190.0 M.<>The projects have started January and February 2013 with an average accomplishment of 82.80%.
  1. Additional Projects

 

Description:

<>Restoration of damaged slope protection along Marikina River (Mouth of Rosario Weir), Pasig City (L- 45 l.m).

 

<>Rehabilitation/Improvement of Tullahan River at Brgy. Nagkaisang Nayon, Quezon City

 

<>Rehabilitation/Improvement of Tullahan River at Brgy. Sta. Lucia, Quezon City

 

<>Repair of Damaged Slope Protection (Boulder Riprap) along Lakeshore Dike at Intermittent Section from Sta. 1+618 to Sta. 10+056 West Mangahan Floodway, Taguig City, Phase I, Gaps from Sta. 1+920 to Sta. 6+896, Taguig City

 

50.9

50.9

<>4 out of the 4 projects have already budget releases amounting to P50.9 M.<>4 of the 4 projects have started February 2013 with an average accomplishment of 80.00% (with 2 projects already completed).
Region III:
  1. Dredging of Labangan Channel, Hagonoy, Bulacan

 

Description:

Dredging works

 

100.0

100.0

<>The project has already budget release amounting to P100.0 M.<>The project is still for bidding.
  1. San Fernando-Sto. Tomas-Minalin Tail Dike

 

Description:

Widening of Pilot Relief Channel from Gugu Creek to Labuan Channel including its confluence with San Francisco River.

139.0

139.0

<>Funds for this project was just released last 14 March 2013 amounting to P139.0 M.<>Bidding for this project is yet to be undertaken.
  1. Mitigation Measures for Breaches in the San Fernando-Sto. Tomas-Minalin Tail Dike

 

<>The project will be implemented in 2 stages, as follows:

 

A.) For immediate implementation (2nd Quarter of 2013) (P515.1 M)

 

Description:

Repair of transverse dike, repair/restoration of Spillway No. 1 and No. 3 and restoration of Pasig-Potrero East Dike.

 

– The above priority emergency works was supplemented to the on-going contract of Toyo Construction Co., Ltd. under the PHUMP-Phase III, CP No. 4, JICA Loan No. PH-P241, considering the urgency to implement the same so as to contain the sediments within the Megadike structure, thereby minimizing channel silt up to the downstream of Gugu Creek and Pasig-Potrero River per prior clearance/authority duly approved by the Honorable Secretary on 23 March 2013.

 

B.) Deferred implementation (4th Quarter of 2013) (P121.9 M)

 

Description:

Diversion channel from Spillway No. 3 to Spillway No. 1 and construction of new 100m bridge across diversion channel and approach road.

 

– The above remaining scope of works is recommended to be implemented at a later period subject to an extensive study through simulation analysis of the hydraulic and sediment transportation to formulate a long-term solution to the present condition of the Pasig-Potrero River.

 

637.0

637.0

<>Funds for this project was just released last 14 March 2013 amounting to P637.0 M.<>The temporary works for the priority emergency works and the Detailed Engineering Design is ongoing.
  1. Del Carmen-Balimbing Creek, City of San Fernando, Pampanga

 

Description:

Extension of the rehabilitation of Del-Carmen-Balimbing Creek, san Fernando, Pampanga.

 

30.0

30.0

<>The project has already budget release amounting to P30.0 M.<>The project has started December 2012 with an accomplishment of 75.00%.
  1. Orani Channel, Bataan

 

Description:

Dredging works

50.0

50.0

<>The project has already budget release amounting to P50.0 M.<>The project has been bid out February 2013 and has been suspended.
Region IV-A:
  1. Sta. Maria-Mabitac River (CP II)

 

Description:

River control/improvement works

 

400.0

400.0

<>The projects were transferred to LLDA by virtue of a Memorandum of Agreement (MOA).<>Funds for the projects were also transferred to LLDA thru a Letter of Advice of Allotment (LAA) but only 50% of the total amount equivalent to P390.0 M was released to facilitate submission of liquidation reports from the LLDA on their fund utilization. The remaining 50% will be released once liquidation reports of the utilization of funds are already submitted.<>2 of the 2 projects have started in 05 April 2013. Soil boring tests, pre-construction and cross-section surveys at 20 m intervals are currently being undertaken by LLDA. 
  1. Sta. Cruz-San Pedro-Biñan Rivers (CP I)

 

Description:

River control/improvement works

 

380.0

380.0

Nationwide:
  1. Various Dredging Equipment

 

Description:

Procurement of Amphibious Excavator and Pontoon Barge with Dumping Bin

 

136.5

136.5

<>The project has already budget release amounting to P136.5 M.<>The project has already secured approval of Authority to Purchase from DBM.<>The project was originally bid out on January 2013 but was declared a failure due to invalid bid submission. Re-bidding was conducted on March 2013 and was also declared a failure. Awaiting BAC Resolution to negotiate as allowed under RA 9184 if 2 failed biddings. 
  1. Operation and Maintenance

 

Description:

Dredging Equipment for Pasac-Delta Waterway, Guagua and Sasmuan, Pampanga

43.5

43.5

<>The project has already budget release amounting to P43.5 M.<>Bidding for fuel and lubricants is yet to be undertaken. Dredgers to be mobilized.
Grand Total:

5,000.0

3,940.452

<>Total Released Amount is equivalent to P3,940.452 M (78.81%).  <>Remaining Balance of Allocation is equivalent to P1,059.548 M

 

 

Note:

The additional proposed projects for Valenzuela-Obando-Meycauayan (VOM), as mentioned above, has a total estimated cost of P 1,883 million. The necessary funds to cover the portion of the same amounting to P779.548 million is proposed to be taken from other proposed projects covered under the P5.0 billion that are yet to be implemented, since, the same need further studies prior to implementation. Further, fund for the necessary consulting services for various proposed flood-control projects amounting to P60 million is also proposed to be taken under the remaining allocation balance of the said P5.0 billion.

Considering however, that only P779.548 million balance of allocation is available, which is P1,103.452 million short of the required P1,883 million for the above additional projects for the VOM Project, the additional fund requirement of the same is proposed to be sourced out from any available budget of the department.

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