The Laguna de Bay
Region is a life support system for more than 10 million people living in
its watershed. People depend on it for food, irrigation, transportation,
flood water reservoir, and industrial cooling, among others. The
conflicting interests of various stakeholders, rapid population growth,
and expanding economic activities continue to become the major threats in
the sustainable development of the lake’s region.
The
lake's most dominant use is on fisheries. It is estimated that the
lake yielded 37,000 to 47,000 MT (metric tons) of fish in 1997 to
2000 - both from the fishpens and open fisheries. Crustaceans and
mollusks declined in yield from 1,927 to 574 MT and from 101,101
to 85,363 MT respectively, during the same period. With the
introduction of the fishpen culture technology in 1970, the boom
in lake fishery production also led to social conflicts in the
region. Large-scale fishpens have threatened the economic
conditions of fishermen dependent upon open water fishery. To
address the issue, a revised Lake
Fishery Zoning and Management Plan
was implemented in 1996.
Transport
Route
LLDA
set navigational routes for lake travelers and users
to avoid conflicts with fish cultivators, fishpen
owners, and free-range fishermen. More than 5,000
motorized and non-motorized watercraft operate as a
means of transportation for lakeshore communities.
In addition, there are 23 barges plying the lake to
transport an average of 75,640 barrels of oil and
oil products to various supply depots daily.
The
following are the traffic lanes for ferry vessels
which starts from Pasig River to Sta. Cruz, Laguna:
a.
Primary
Lane- a 500 meter wide route going to Los Baños,
and Pagsanjan, Laguna.
b.
Secondary
Lane - a 400 meter wide route provides access to
other municipalities around the lake including Talim Island.
c.
Tertiary
Lane - a 200 meter wide route which lead to the
existing landing areas in the municipalities.
Flood
Water Reservoir
The
lake also serves as a reservoir for floodwater to save Metro
Manila from flooding. The Manggahan Floodway was constructed to
divert floodwaters from Marikina River into the lake. The Napindan
control station regulates the outflow of excess lake waters and
minimizes the inflow of saline water and pollution from the Pasig
River.
Power
Generation
Laguna
de Bay is also used for power generation; three power plants are
located in the region. A pump storage hydroelectric power
station is operated in Kalayaan, Laguna. Water is pumped up
to the Caliraya Reservoir to generate about 300 megawatts of
electricity. Efforts are underway to increase this capacity
to 600 megawatts.
Recreation
Laguna
de Bay is also known for recreational activities. Although classified
only for non contact recreation such as fishing, boating and sailing,
the lake is used for swimming in some communities. Lakeshore resorts
near Mt. Makiling extract hot spring waters for health spa and beauty
treatment. LLDA also ventures on eco-tourism projects through
the LISCOP
Component 1 Project.
Irrigation
Laguna
de Bay also provides sufficient water for farm lands of the lake
region. Studies are being done to further improve the use of lake
water for agriculture.
Industrial
Cooling
The
lake is also being used as a source of industrial cooling water. Major
users include the National Power Corporation for the Kalayaan
Hydropower Plant and the Philippine Petroleum Corporation Refinery in
Pililla, Rizal. KEPHILCO-Malaya Power plant also draws water from the
lake for cooling. Cooling water is recycled back into the lake
resulting in thermal pollution of about 20C rise in temperature near
the discharge points.
Waste
Sink
The
lake also serves as a huge waste sink for solid and liquid waste
coming from households, cropland areas, industries, livestock and
poultry production as well as fishery activities. Because not a
single municipality is equipped with a sewerage system, pollution
is carried as surface run-off through the sub-basins of the lake.
In addition, polluted waters from the Marikina and Pasig Rivers
also flow into the lake.
Waste
Supply
With a rapidly increasing regional population
coupled by inadequate surface water production in the Angat Region
and generally declining ground water resource, the lake water is
now seen as a major source of potable water supply.
As
of 2005, the estimated population in the Laguna de Bay Region is about
13.2 million. It is projected that the population in the lake region will
grow at a rate of 2.25 percent per year. The western portion or those
areas near Metro Manila will continue to become denser than the eastern
portion.
However,
the direction of population growth shows that population spreads from
Metro Manila towards the towns and cities of Rizal, Laguna, Cavite, and
Batangas. There will be a gradual expansion of population towards the
eastern and southwestern portion.Moreover,
population in the shoreland is likewise increasing. The highest population
is projected to occur in Metro Manila and the provinces of Cavite, and
Rizal.
Maps
below show the administrative maps rendering the corresponding
population gradients per municipality.
Maps below show the simulated
watershed maps rendering the corresponding population density
gradients per microwatershed.
The
Gross Regional Domestic Product of the lake region, as of 2005, amounted
to P101.3 billion. This contributed 12.8 percent to the 1995 country’s
GDP of P788.9 billion.
There are more than 3,000 industries
registered to LLDA. These industries and business establishments were
classified according to the type of pollution they discharged.
1. Food manufacturing
11. Minerals and non-metals
2. Pulp and paper
manufacturing
12. Laundry
3. Dye, textile, garments,
sewing
13. Wood
4. Piggeries, poultry,
livestock
14. Rubber and leather
5. Slaughterhouse, hatchery
15. Plastic, film, foam
6. Beverages
16. Gasoline station
7. Semiconductor, electrical
17. Industrial estate,
dumpsite
8. Metal
18. Housing, recreation
9. Agricultural
19. Power plant
10. Chemicals,
pharmaceuticals
20. Transportation
21. Fast food chains
Satellite
images give an actual picture of the density of population and economic
activities in the whole Laguna de Bay region. In a 2002 satellite image
(shown below), the stark difference between the western and eastern part of
the lake is very apparent- the former (blue area) has higher population
density and intensity of economic activities than the latter (reddish
brown area). Population in the shoreland is also becoming dense.
