By Dhel Nazario
Through the country’s very own microsatellite Diwata-1, local authorities may be able to get a better look at the progress of the rehabilitation efforts in Manila Bay, and could even provide images showing changes in its water quality.
In a statement, the Department of Science and Technology (DOST) said that satellite images, such as those provided by Diwata-1, could provide timely and periodic information that could help the rehabilitation project.
“In ideal conditions, satellite images can help us track the temporal changes of turbidity within Manila Bay helping the efforts of the government to rehabilitate the bay,” it added.
A year ago before the rehabilitation project, Diwata-1 was able to capture an image of Manila Bay using its Spaceborne Multispectral Imager. An analysis of turbidity, using the Formazin Nephelometric Unit (FNU) to measure water clarity, shows unmistakably turbid murky waters at the mouth of Pasig River appearing to flow out from inside the river.
Figures from the microsatellite point to the built-up areas inside the river as a source of pollutants.
“This means that residential and industrial runoffs, such as wastewater from factories, are dumped onto the river. It is important to note that for the successful long-term rehabilitation of Manila Bay, the sources of pollution that enter the river, as well as other river systems that drain to the bay, should be identified and regulated as well.” The agency said.
The images also showed that turbid waters are also present at the shores of Bulacan and Pampanga due to “aquaculture”. Masses of aquaculture farms set up for intensive fish farming; an activity commonly associated with using fish feed and fertilizers cause contamination in the water that reaches the Manila Bay due its unregulated use.
The DOST said that diversifying and promoting alternative ways for aquaculture should be explored, as limiting aquaculture activities in this area—a possible effect of the Manila Bay Rehabilitation Project— may lead to a food supply crisis.
Through the images, a multitude of sources of the bay’s pollution could also be observed. These sources can be easily identified by satellite images such as those provided by the Diwata microsatellites.
With Diwata-2’s revisit capability, certain high-priority areas such as Manila Bay can be better monitored to compare water quality changes over time. Also, remote sensing; a feat of both Diwata 1 and 2 is a cost-effective way to conduct large-scale assessments of water quality at the bay as both satellites are capable of capturing large areas of the bay to be used for water quality assessments.