Frequently  Asked  Question

 

 

What is the significance of Laguna de Bay?

Why is Laguna de Bay considered a Living Lake?

What is the relationship of Pasig River, Laguna de Bay & Manila Bay?

How important is Laguna de Bay to the people?

What are the potentials  of the lake for water supply?

How do communities contribute to the pollution of the lake and its tributaries?

What is BIOLOGICAL POLLUTION?

What are the causes of fishkill?

What is the current situation along the lakeshore of Laguna de Bay?

Is Laguna de Bay a safe source of water for drinking?

How many metric tons of fish can Laguna de Bay support?

What are the sources of recharge of Laguna de Bay?

What is the only outlet of Laguna de Bay?

What areas are covered by the LLDA Administrative Jurisdiction?

Who composes the LLDA Board of Directors?

What is the Environmental User Fee System?

Why is it that fishpens are concentrated in the West Bay?

How many metric tons of fish does Laguna de Bay produce from aquaculture?

What are the problems on lake fisheries?

What is the Zoning and Management Plan?

What are the Challenges in the Implementation of the Zoning and Management Plan?

How many fisherfolk families depend on the Lake as a source of livelihood?

Why is Laguna de Bay extremely stressed?

Is Laguna de Bay an adequate source of bulk raw water for drinking?

 


What is the significance of Laguna de Bay ? 

Laguna de Bay  The largest and most vital inland water body in the Philippines.

18th Member of the World’s Living Lakes Network.

22 Lakes now forms part of the Network.


Why is Laguna de Bay considered a Living Lake?

Dissolved Oxygen concentration is above (5.6 – 11.7 mg/L) the set criterion of 5mg/L for fishery. (EQMD WQ Monitoring Report, 2005).

Biochemical Oxygen Demand concentration is below (.1 – 7 mg/L) the prescribed limit of 10 mg/L. (EQMD WQ Monitoring Report, 2005).

The natural food in the Lake continues to support an estimated  338,415 metric tons of fish in the  open waters. (Lake Primary Productivity Studies, 2005).

Aquaculture structures in the Lake produces an estimated 85,000 metric tons of fish per year (Laguna de Bay Environment Monitor, 2005.).

The Lake continues to supply the  domestic and industrial water requirements of certain establishments, public and private, within the LdBR.


What is the relationship of Pasig River, Laguna de Bay & Manila Bay? 

The Pasig River is an important component of the lake ecosystem. It is the only outlet of the lake but serves also as an inlet whenever the lake level is lower than Manila Bay. 


How important is Laguna de Bay to the people?

Life support system to about 13 million people of whom 3.5 million live along the lakeshore areas.


What are the potentials  of the lake for water supply?
More than 400,000 people in Metro Manila are  already suffering from water shortage.
A private water company already draws approx.  300,000 m3 of water per month.

How do communities contribute to the pollution of the lake and its tributaries?

By using it as a waste sink-Sewerage canals in 61 cities and towns within Laguna de Bay Region empty into 21 tributary rivers which all drain into the lake. Manila Bay also channels polluted waters into the lake daily via the Pasig River due to tidal flows.


What is BIOLOGICAL POLLUTION?

Proliferation of non-native  species, most recent of  which is the janitor fish.


What are the causes of fishkill?

River flushing/flashflood.

Infestation (kurikong, kuto).

Algal bloom.


What is the current situation along the lakeshore of Laguna de Bay?

Conflicts existing among users/uses or the zoning  priorities and jurisdictions.

Encroachment in the lake is prevalent causing intrusions of pollutants into the lake water.


Is Laguna de Bay a safe source of water for drinking?

The Lake provides safe drinking water with appropriate treatment. (LLDA Case Study on Drinking Water Supply with LdB as Raw Water Source; Netherlands funded Sustainable Development of LdB Environment Project, 2000-2003).


How many metric tons of fish can Laguna de Bay support?

The natural food in the Lake can support 338,415 metric tons of fish in the  open waters (Lake Primary Productivity, 2005).


What are the sources of recharge of Laguna de Bay?

The sources of recharge of Laguna de Bay come from the 21 Major Tributary Rivers (14% Pagsanjan-Lumban River, 7% Sta. Cruz River, 79% from the 19 remaining tributary rivers).


What is the only outlet of Laguna de Bay?

The only outlet of Laguna de Bay is the Pasig River.  However, it also serves as a source of saline water during summer months.  This phenomenon is called the Pasig River Backflow.


What areas are covered by the LLDA Administrative Jurisdiction?

LLDA's Administrative Jurisdiction covers the provinces of Rizal (13 towns and 1 city), Laguna (27 towns and 3 cities), Cavite (3 towns and 1 city), Batangas (2 towns and 1 city), Quezon (1 town) and Metro-Manila (2 towns and 7 cities).


Who composes the LLDA Board of Directors?

The LLDA Board of Directors is composed of the following:  Representative of the Office of the President, The Secretary of the Department of Environment and Natural Resource, The Secretary of the Department of Trade and Industry, The Secretary of National Economic Development Administration, The Governor of the Province of Laguna, The Governor of the Province of Rizal, The Chairman of the Metro-Manila Development Authority, The Presidents of the League of municipalities in the Provinces of Laguna and Rizal, The Representative of the Private Investors and the General Manager of the LLDA.


What is the Environmental User Fee System?

The Environmental User Fee System is a pioneer market based instrument for pollution control and abatement in the Philippines.  It aims to reduce pollution and improve water quality by encouraging the industries to invest in treatment systems.

Why is Chemical Oxygen Demand (COD) considered as an  Adequate Charging Parameter for Environmental User Fee System? 

It  better represents   the total organic pollution load of industries (Bio-chemical Oxygen Demand [BOD] is often an underestimation of the real oxygen demand of industrial wastewaters).  

It has less interference of toxic substances which could negatively influence the BOD test. 

It has easier,  more accurate and reliable and more replicable methods of analysis.


Why is it that fishpens are concentrated in the West Bay?

It is considered the most productive  in terms of primary productivity and existence of nutrients.

It is more protected from the elements like strong wind velocity and wave action.

The bottom sediments are more desirable compared to  south west portion of the Lake which has rocky bottom sediments.

How many metric tons of fish does Laguna de Bay produce from aquaculture? 

The Lake produces 85,000 metric tons of fish per  year from aquaculture  (LdB Environment Monitor, 2005).


What are the problems on lake fisheries?

Overfishing.

Declining fish production.


What is the Zoning and Management Plan?

The Zoning and Management Plan for Aquaculture structures in Laguna de Bay is a management system for equitable allocation of the lake’s fishery resources.  It prescribes the area allocation and defines the fishpen/cage layout, fish sanctuaries and open fishing, navigational access channels. The Plan also provides the criteria, guidelines and procedures for proper allocation of aquaculture structures.


What are the Challenges in the Implementation of the Zoning and Management Plan?

Over stocking.

Improper waste management in fishpen guardhouses.

Non-observance of required distances between structures.

Exceedance to the 10,000 ha. limit.


How many fisherfolk families depend on the Lake as a source of livelihood?

There are approximately 28,000 fisherfolk familiies that depend on the Lake as a source of Livelihood (BAS and FARMCs, 2000).


Laguna de Bay is extremely stressed because of the following:

 

** Increasing trend in BOD primarily due to domestic (close to 80%) and industrial wastes  (some 11.5%), and as a result of Pasig River backflow.  Nevertheless, the Lake’s BOD concentration is still within the criterion. (Laguna de Bay Environment Monitor, 2005) 

** Seasonal fluctuations in nitrate and phosphate concentration. Lack of centralized or localized sewage treatment perpetuates inflow of nitrogen & phosphorous which brings about eutrophication.  (Millennium Philippine Sub-Global Assessment, 2005) 

** There are some traces of heavy metals in Lake water and sediments, although concentration is still within prescribed safe levels.  (LLDA-UP NIGS Study on Sedimentation Pattern, 1999) 

** Decreased counts of aquatic plants. (LLDA Monitoring Sampling Data) 

** The Lake is undergoing rapid shoaling. Average depth is 2.5m in 2003 as compared to 2.78m in 1973. (LLDA-UP NIGS Study on Sedimentation Pattern, 1999; Sustainable Development of the LdB Environment Project, 2000-2003).


Is Laguna de Bay an adequate source of bulk raw water for drinking?

** The Lake has an average volume of 2.25B m3 (SOGREAH Report, 1973) 

** 1000MLD* (400 MLD for water supply & current 600 MLD for irrigation & other uses) is projected to decrease water level by only 1.1 mm/day or 13.3 cm during dry months (Jan-April). This is only 9.5% of total annual average water inflow from tributaries. (Sustainable Development of the LdB Environment Project, 2000-2003) 

** Different alternative engineering schemes have already been drawn where the Lake and Pagsanjan River are considered as  probable raw water sources. (Study on Engineering Alternatives for the 300 MLD Bulk Water Supply Project, September 2000; Sustainable Development of the LdB Environment Project, 2000-2003) 

** Existing MWSS water supply sources are insufficient to meet the requirements of its service areas.

    -- In April, 2004 MWSS solicited proposals for the  delivery of 400 MLD  treated bulk water to its concessionaires, without limiting the source to LDB (MWSS Consolidated FS on 400 MLD Bulk Water Supply Project;  NEDA Report). 

    -- MWSS is yet to await DOJ-OGCC opinion whether to proceed with the supply of 300 MLD thru BOT

 

 

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