Scenario

Sanitation interventions in the Philippines have been limited to centralized sewerage systems in highly urbanized centers: Metro Manila, Baguio , Vigan and Zamboanga. Even these systems have very limited scope, with Metro Manila being served by two private concessionaires at 4% of its share of population while the other three cities have sewerage systems serving less than 3% of its service area population.

The dismal coverage of sanitation facilities in the country is not surprising. Sanitation has been largely a private responsibility where the construction of septic tanks is required by the local building codes. In the same manner that private households are responsible for the construction and maintenance of their own septic tanks, industries are also responsible in ensuring the treatment of their wastewater monitored through the discharge permit issued by the Environmental Management Bureau of the DENR. Wastewater treatment to reduce pollutants to acceptable levels is required prior to discharge into the combined sewage-drainage systems or open waterways such as creeks.

The treatment process depends on the characteristics of the wastewater. Domestic (or household) wastewater is mostly similar in most homes, mainly from the kitchen, bathroom and laundry. Industrial and commercial wastewater, however, may have higher organic and solid content – sometimes even toxic and hazardous (e.g. hospital wastes). Pre-treatment is therefore sometimes necessary to target the pollutants and reduce it to domestic wastewater quality. Industrial wastewater ranks behind domestic and agricultural wastewater in contributing organic waste and BOD pollution at the national level. This value, however, varies on a regional basis as exemplified by Metro Manila and Region IV with the highest amount of industrial BOD at 43 and 14 percent respectively.

Characteristics of industrial wastewater vary depending on the scale and process of production but are considered more polluting than domestic wastewater. Conventional sanitation systems require high cost of investment and maintenance. With environmental standards becoming more stringent, alternatives to centralized systems are gaining more significance.

Case Study
Wastewater Treatment Plant

Final Component of the Integrated Management Scheme for Small and Medium Scale Slaughterhouses

Animal Products Development Center-Bureau of Animal Industry (APDC-BAI)

Despite its significant contribution in the agriculture sector, the animal industry is facing serious concerns in the handling and processing of animal meat products. An estimated 10 million livestock (primarily swine and cattle) and 206 million poultry were slaughtered in 2004 mainly for domestic meat supply. This volume of livestock and poultry are handled by 129 slaughterhouses accredited by the Department of Agriculture. The large numbers of animals processed by these slaughterhouses poses a concern on waste management and handling of by-products.

The management and operation of slaughterhouses (or abattoirs) encompasses handling of food animals from the stockyard until it is dispatched in the form of carcasses and other secondary by-products. The different stages of the process involve substantial volume of solid and liquid waste such as inedible animal by-products, dead animals and highly organic wastewater effluents. While slaughterhouses are required to treat their wastewater before releasing it to the environment, most slaughterhouses do not meet national regulation standards. If not properly managed, these wastes cause serious pollution problems, contaminated meat products and spread of food-borne diseases that are threats to both human and livestock.

The Animal Products Development Center-Bureau of Animal Industry (APDC-BAI) is responsible for the development and extension of appropriate technologies to improve methods of handling, processing and utilization of animal products and by-products to meet international standards on hygiene and workflow. The APDC in partnership with the Bremen Overseas Research and Development Association (BORDA), Basic Needs Services Philippines (BNS) and the German Technical Cooperation (GTZ) Water and Sanitation Program introduced a pilot integrated waste management scheme for small and medium scale slaughterhouses.

Wastewater from slaughterhouse is composed of mainly diluted blood, fat, suspended solids and may contain manure. Its major characteristics are high organic strength, sufficient organic nutrients, adequate alkalinity, relatively high temperature and comparatively free of toxic materials. An anaerobic (without oxygen) treatment system was designed to fit the slaughterhouse condition and meet the requested treated wastewater discharge standard. The scheme introduced at the APDC-BAI includes waste separation and collection as well as transformation of solid and liquid wastes into valuable products. Biogas is one such by-product of anaerobic decomposition of organic matter. The gas produced from the treatment process is used to heat water for cleaning of offal and removal of body hairs.

The wastewater treatment designed for APDC-BAI has the capacity to treat a maximum of 10 m 3 wastewater discharged daily or equal to the volume of wastewater from slaughtering 30 hogs and 10 cattle per day. Currently, BAI only slaughters 10-15 heads of cattle on Monday, Wednesday and Friday and about 20-25 heads of hog on Tuesday and Thursday. The construction cost is an estimated Php 500,000 with projected monthly maintenance and operation cost of Php 2,000 only. The system only requires simple operation and maintenance with monitoring of effluent quality on a regular basis.

The APDC waste management approach serve as a showcase for the sustainable operation of small and medium scale slaughterhouses at the national and regional level. The integrated management of slaughterhouse waste significantly reduces the amount of pollutants in the final discharge released to the environment. Consumers also benefit from the hygienic processing of meat and by-products and the threat of contamination from food-borne diseases are minimized.

The agriculture sector contributes significantly in the country’s gross domestic product with the livestock and poultry subsector putting in a considerable 29% in total agricultural output with gross production valued at P262 billion at current prices. Improvements in livestock and poultry production are a welcome relief for the agriculture sector whose share in the GDP has been continuously declining in the last three years. Also, the animal industry has to keep up with the demands of a growing population with 84 million Filipinos, rapidly growing at 2.36 percent annually.

The wastewater treatment system at the APDC-BAI is an answer to the need to upgrade slaughterhouse facilities to meet the increasing demand brought by the rapid growth of the meat and livestock sector. Overall, the animal industry benefits from the effective, efficient and affordable wastewater treatment solution designed for slaughterhouse conditions as it contributes to the growth of the national economy and local food security.