The state of water resources in the Philippines - Greenpeace

Total suspended solids (TSS)
TSS parameter measures the amount of undissolved solid particles in water such
as level of siltation, decaying plant and animal matter, and domestic and
industrial wastes. For water bodies used for water supply the standard for TSS is
25 mg/L for Class AA and 50 mg/L for Class A (EMB, 2006).
Out of forty-six Class A/AA water bodies monitored for TSS, about 23 percent
have good water quality, 69 percent have fair water quality, and eight percent
have high TSS levels, indicating poor water quality. Among those with poor
water quality are: Pampanga River in Region III, Bicol River in Region V, and
Iponan and Alubijid Rivers in Region X.
According to EMB, the presence of a high percentage of TSS confirms the effects
of sand and gravel quarrying activities and runoff from denuded forests and
agricultural lands.
Total dissolved solids (TDS)
TDS is generally used as an aggregate indicator of the presence of a broad array
of chemical contaminants. The primary sources of TDS in receiving waters are
agricultural runoff, leaching of soil contamination, and point source water
pollution from industrial or domestic sewage (EMB, 2006).
For water bodies classified as Class AA, the standard for TDS levels is expected
not to exceed 500 mg/L and 1,000 mg/L for both Class A and D waters.
Of the 30 monitored Class AA/A water bodies, three have two classifications;
hence, a total of 33 classifications. About 55 percent have good TDS levels,
which mean that these water bodies comply with set water quality criteria based
on their intended beneficial use. Forty-two percent have fair TDS levels and only
Marilao River has poor water quality, with annual average TDS levels ranging
from 1,785 to 3,265 mg/L.
Heavy metals
EMB reports that heavy metals are parameters included in monitoring activities
only for receiving water bodies where mining, electroplating, tanning, and other
similar activities are operating.
Among inland surface waters, only Meycauayan, Bocaue, and Marilao Rivers
have been monitored. Annual average monitoring results of Meycauayan River in
2001, 2003, and 2004 show an excess (based on minimum criteria and value) for
chromium (2001), cadmium (2001), and lead (2004) (EMB, 2006).
Monitoring results of Bocaue River indicate that the River met the criteria for
chromium, copper, and cadmium. However, it showed high lead concentrations in
all its sampling stations particularly during the dry season in 2004. The Marilao
River showed similar excess (relative to existing standards) in lead and cadmium
in its Class A and C waters. Potential sources of heavy metals are tanneries,
electroplating, and other similar industries located in nearby areas.
GREENPEACE | The state of water in the Philippines 16