ASSESSMENT OF PASIG RIVER AND MANILA BAY

MANILA BAY:

Manila Bay is a natural harbour which serves the port of manila (on luzon), in the philippines.The bay is considered to be one of the best natural harbours in southeast asia and one of the finest in the world. Strategically located around the capital city of the philippines, Manila Bay facilitated commerce and trade between the Philippines and its neighbouring countries,becoming the gateway for socio-economic development even prior to Spanish occupation. With an area of 1,994 km2 (769.9 sq mi), and a coastline of 190 km (118.1 mi), Manila Bay is situated in the western part of Luzon and is bounded by cavite and metro manila on the east, bulacan and pampangga on the north, and bataan on the west and northwest. Manila Bay drains approximately 17,000 km2 (6,563.7 sq mi) of watershed area, with the pampangga river contributing about 49% of the freshwater influx. With an average depth of 17 m (55.8 ft), it is estimated to have a total volume of 28.9 billion cubic metres (28.9 cubic km). Entrance to the bay is 19 km (11.8 mi) wide and expands to a width of 48 km (29.8 mi). However, width of the bay varies from 22 km (13.7 mi) at its mouth and expanding to 60 km (37.3 mi) at its widest point.

• POLLUTION

  With the presence of ports, sea-based sources of pollution around the bay are from ships and motorized boats. Twelve oil spills were recorded in 1995, but it was in 1999 where the highest total volume of oil spill occurred in the Manila South Harbor and Limay, Bataan. Increased presence of oil and grease in the waters are attributed to maritime activities at the harbors, together with the presence of oil terminals and the discharges from industries.These factors directly impacted the health of Manila Bay's waters. Aside from oil spills, trace metals such as copper, cadmium and zinc at the surface of the water were found at the bay coming from sea-based and land-based (e.g., domestic sewage, industrial effluents, runoff, combustion emissions, and mining operations)sources. In 1996, concentrations of 16 commonly used pesticides in surface sediment was found including dichloro-diphenyl-trichloroethane (DDT). Polycyclic aromatic hydrocarbons (PAH) found in Manila Bay sediments have been influenced by human activities. PAH come principally from petrogenic sources (e.g., oil discharges from ships, refineries and industries) and pyrolytic sources (from combustion sources).Pesticide residues from rice paddy water draining into irrigation canals, which later on empty into river systems and eventually flowing into the surrounding lakes reaches the waters of Manila Bay. Compounds from these pesticide residues find themselves in food items with metamidophos, endosulfan, chlorpyrifus and diazinon among the common contaminants. While chronic toxic effects on inhabitants of the bay are not found, impairment of marine biota were more evident. In 1997, polychlorinated biphenly congeners (PCBs), compounds common in transformers, hydraulic fluids, paint additives and pesticides were determined in sediments and oysters sampled from Manila Bay. The increase in the nutrient concentration and presence of nitrate, ammonia and phosphate in the bay,from the '80s, through to the '90s and beyond are not only attributed to agricultural runoff and river discharges but also on fertilizers from fishponds.

PASIG RIVER:

 The Pasig River is technically a tidal estuary, as the flow direction depends upon the water-level difference between Manila Bay and Laguna de Bay. During the dry season, the water level in Laguna de Bay is low and the flow direction of the Pasig River depends on the tides. During the wet season, when the water level of Laguna de Bay is high, flow is normally from Laguna de Bay towards Manila Bay. The Pasig River used to be an important transport route in Spanish manila. Due to negligence and industrial development, the river has become very polluted and is considered dead (unable to sustain life) by ecologist. The Pasig River Rehabillitation Commission (PRRC) was established to oversee rehabilitation efforts for the river. Supporting the PRRC are private sector organizations, i.e. 

• POLLUTION

  After World War II, massive population growth, infrastructure construction, and the dispersal of economic activities to Manila's suburbs left the river neglected. The banks of the river attracted informal settlers and the remaining factories dumped their wastes into the river, making it effectively a huge sewer system. Industrialization had already polluted the river. In the 1930s, observers noticed the increasing pollution of the river, as fish migration from Laguna de Bay diminished. People ceased using the river's water for laundering in the 1960s, and ferry transport declined. By the 1970s, the river started to emanate offensive smells, and in the 1980s, fishing in the river was prohibited. By the 1990s, the Pasig River was considered biologically dead.
  

   

MEMEBERS:

JAN CYRILE BARAQUIEL

CELINA GAMIS

JOHN CRUZ

KEVIN HUERTAS

ANGELO GARCIA

CHOLO QUERIDO