Philippines - Water Districts Development Project : environmental assessment summary (Vol. 3 of 5)

H*;,,.~~~~~~~, Is ~~ ' 9.i 4j~4 ~ '~4'~4~t . ~. '9 4 V1,~~~~~~~~~~', 9.  - w Z ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  Republic of the Philippines Local Water Utilities Administration SEWERAGE AND SANITATION PROJECT WATER DISTRICT DEVELOPMENT PROJECT o . WORLD BANK ENVIRONMENTAL 1 X ~LUZON ASSESSMENT REPORT CALAMBA, LAGUNA / t ASAKAS X9YA MINDANAO 0 go~~~~~ August 1997 ______~~~~----------------  0  TABLE OF CONTENTS Page EXECUTIVE SUMMARY 1 Chapter 1 INTRODUCTION 12 Chapter 2 BASELINE ENVIRONMENT - CALAMBA, LAGUNA 16 Section I Existing Environment 16 Section II Environmental Pollution 18 Chapter 3 PROJECT DESCRIPTsION AND ANALYSIS OF ALTERNATIVES 24 Section I Project Rationale and Objectives 24 Section H Sanitation 25 Section III Overall Sewerage Scheme 27 Section rV Recommended Project Design for Calamba, Laguna 40 Section V No Project Scenario 43 Chapter 4 ENVIRONMENTAL IMPACTS 46 Section I Beneficial Impacts of the Project 46 Section II Project Implementation Impacts 48 Section IH Summary 50 Chapter 5 ENVIRONMENTAL MANAGEMENT PLAN 51 Section I Mitigation Plan 51 Section II Monitoring Plan 53 Section III Implementing Arrangements 54 Appendices 1. Bibliography 2. Cimatological Normals (1961-1995) 3 Typical Noise Emissions of Construction Equipment 4. Expected Noise Levels at Various Distances from Construction Equipment 5. Environmental Quality Standards For Noise Maximum Allowable Noise lIevels 6. The Advanced Integrated Pond Svstem iA[PS) of Wastewater Treatment I:I7vIHflhtflenrai- I.'lxse.xvnielt tepnpt. ( 'alam7n a. ,'1tlv 1  4 I  EXECUTIVE SUMMARY Introduction In the Philippines, the typical urban area/built-up area is characterized by a heavy concentration of activities, both commercial and industrial It is also the area where the di isity of population is at its highest. These areas are also the sites where the production and co.surnption of raw and processed materials could be found. Consequently the, pressure on the fife support systems in these areas are far higher than the suburban and rural areas. Adverse environmental conditions such as the generation and similarly the discharge of wastes into the environment is common in urban and built-up areas. Unfortumately, the amount, type and concentration of waste generated exceed the capacity of the local environment to absorb and assimilate them The carrying capacity of the life support svstems are stretched to the hmits. The urgency of establishing collection and treatment mietlhods to prevent adverse imtpacts to the health and wefl-being of the residents, and to the ecological systems which sustain them cannot be ignored and overstated. Most urban centers in the Philippines rely on individual septic tank systems for the treatment and disposal of wastewater from domestic and commercial buildings. However, the designs for such systems is often inadequate. Facilities for land disposal of effluents from the septic tanks are generally absent. Hence, the partially treated septic tank effluents flow directly into storm drainage systems and other receiving bodies of water, thereby exacerbating an already grave pollution situation. There are several possible options for addressing this problem, including improving the design of the septic tank system with the installation of soil absorption systems. But an environmentally sound alternative that is cost-effective and captures economies of scale is to connect individual properties directly to a sewerage system for the collection, treatment and disposal of the urban wastes. The provision of a cost-effective centralized wastewater collection, treatment, and disposal is the primary objective of the proposed Water Districts Development Project. The proposed project will assist the local govemment units (LGUs) of Dagupan City, Calamba (Laguna), Cagayan de Oro City. Davao City and Cotabato City, in finding solutions to the problem of sanitation. Financing assistance will be partly provided by the World Bank (WB) which shall be conduited through the Land Bank of the Philippines (LBP). Over-all administration will be exercised by LBP's Project Management Office (PMO) with technical support provided by the Central Sewerage and Sanitation Program Support Office (CPSO) of the Local Water Utilities Administration (LWUA). /~/171'1r(,1lf7C',)IaI I. L'%"EfJ7f ILRpfrI ( ala ihn. /.'unu  Better sanitary conditions will thus be achieved in the areas served by the sewerage, drainage and sanitation systems. This will reduce water-borne pollution and water-logging within the cities and in the surrounding water bodies, thereby bringing health benefits to local populations. The construction of the systems will protect shallow groundwater aquifers from contamination. Environmental Assessment Requirements This Environmental Impact Assessment Report for Calamba has been prepared in accordance with the Presidential Decree No. 1586 otherwise known as the Environmental Impact Assessment Law and Departmenit of Enivironment anid Natural Resources (DENR) Revise -' Administrative Order Nos. 36, the Revised Water Usage and Classification/Water Qualit Criteria and Revised Effluent Regulations of 1990 respectively; and World Bank's Operational Directive 4.01 on Environtmlenital Assessment. The revised Administrative Order 36 for Environmental Impact Statement System issued in 1996 is comprehensive and is compatible vith the World Bank's Operational Directive 4.01. It outlines the procedure to be followed by environmental critical projects (ECPs) and projects to be located in environmental critical areas (ECAs), in preparing environmental impacts statement (EISs)'. ECP and ECA are defined in the AO. It should also be noted that that local ordinances and regulations governing projects of such nature have been taken into consideration in preparing this report. Similar EIA reports are being prepared for the other 4 cities. This report has been prepared by a team of local consultants under the aegis of the LWUA and the Calamba Government. Much of the work relating to the environmental impact analysis was undertaken as part of the feasibility study done by C. Lotti and Associati. Consultation with the community is an on-going process. The sanitation component of the project wil be executed in a participatory manner, and detailed guidelines have been spelled out. Selection of Priority Cities T'he choice of the first batch of Philippine cities for sewerage investments was made after an initial screening at the national level of urban areas facing the most serious problem of pollution by untreated wastes. Of the five cities, Davao and Cagayan de Oro represent the largest class of provincial cities with current population estimates in the range of a million and half a million respectively. There are several major population concentrations in the city - each being a source of sewage contamination for nearby surface and ground water. However, the largest volume of sewage is generated by the largest consumers of piped water supply; in the Central Business District or Poblacion area. Untreated wastewater from this area has polluted low-lyiig coastal areas. and basically converted the principal rivers into open sewers. The scale of the pollutioll problem can be appreciated by the fact that about 90 per cent of the daily water supply of 140,000 cubic meters in Davao city and 76.000 cubic meters in Cagayan de Oro is being discharged as untreated or undertreated This is tihe term used by DENR and refers to the standard Environmental Assessment Report required by the World bank as per OD 4.01 1Fnvironn71uW0al . Ise.vsrnent Report: (Calamna. L.c?gfla  wastewater. Outside the Poblacion areas, there are pockets of population concentrations polluting nearby streams, creeks and drainage channels. In the other three cities of medium size (Cotabato City, Calamba and Dagupan City), current population estimates are close to 200,000. While the scale of urban pollution problems are not comparable with Davao and Cagayan de Oro, these cities are located close to environmentally sensitive wetlands and water bodies. In Cotabato City, the urban area is actually below the mean sea leveL exposing inhabitants to frequent flooding and waterlogging during the monsoon months. Calamba is located on the shores of Laguna Lake, which has experienced a rapid deterioration in water quality over the last two decades. Dagupan city is close to a large estuarine zone with ecologically sensit 'e wetlands and fishponds. In each of these cities, Mayors and city officials have rc..ognized for some time that unless their complex environmental problems are tackled through a strategic plan of handling waste disposaL sustainability of urban growth could be seriously affected. Overall Project Approach The proposed project follows a demand-based approach in the sense that facilities will be constructed only if they conform with the preferences of local stakeholders, and services conform to their respective willingness to pay. The stakeholders represent the different tiers of organizations from the City/Municipal Council and Barangay (part of the formal LGU system), to the more informal purok, neighborhood and household levels. During project preparation, the idea of involving communities in the planning process was field- tested in three barangays of Davao city. and found to be quite successful. The basic decision-making process is as follows: For the capital-intensive trunk system, consisting of the main transportation sewers, primary drains and wastewater treatment facilities, the project design and implementation plan has to be approved by the City CounciL because the latter is responsible to repay the loan [see Annex 3 of the Staff Appraisal Report (SAR) for the Project on Financial Aspects]. For the feeder system, consisting of collector sewers, secondary drains and on-site sanitation facilities. barangays and local neighborhoods will be associated with the planning and implementation program. The design criteria have been simplified, so that the feeder system can respond to local preferences and willingness to pay, rather than be bound by any conventional sewer design criteria used in industriahzed countries. Detailed design will be conducted through a participatory process described in Annex 13 of the SAR. Given the capital-intensive natur-e of the investments, the proposed project is only the initial phase of a program to improve the sanlitation infrastructure through a strategic plannIing approach that involves a mix of on-site and off-site wastewater collection. treatment and disposal. Choice of initial service areas for sewerage lhas been confined to 1;flvr me7lntal . lx.soxLvnhient RJlepori ( 'alatnb. 3.  the Central Business Districts or Poblacion areas because these are the major contributors to municipal wastewater pollution. The only exception made is in the case of Davao City, where a second area of high growth prospects (Toril) has also been included on the request of the LGU. The project wil construct a sewer network that wil discharge sewage to a vertically integrated pond system designed to treat both sewage and septage. In each of the cities, with the exception of Davao', the treatment site was selected in areas free from encumbrances. For the sanitation components, the entire municipality has been included in the project area, with final selections being made on the basis of demand. On-site treatment systems through the construction of VIP (ventilated improved pit) latrines, pit latrines, pour flush toilets and septic tanks will also be constructed if there is demand from property owners. For those properties with uncertain land tenure (as in squatter settlements), the project will finance the construction of communal toilets, to be managed by non-governmental organizations (NGOs) and/or the private sector. The specific locations of these facilities will be driven by the willingness to pay for the services by beneficiaries at the barangay leveL provided of course that these are technically feasible. Analysis of Alternatives T-he recommended solutions for wastewater treatment were arrived at after an intensive process of evaluating alternatives durinlg the project preparation in order to achieve cost effectiveness and acceptability. The alternatives considered were anaerobic/facultative ponds, modified lagoon systems and mechanical treatment. The evaluation of altematives indicated that the modified lagoon systems, despite having a higher operation & maintenance (O&M) costs compared to anaerobic/facultative ponds (as it requires mechanical aerators and recirculation pumps) was appropriate. The selected option met the following criteria the effectively: Minimize overall pond area required Mininize odor production Meet DENR effluent quality criteria, including fecal coliform reduction Minimize sludge production rate Maximize potential to use surounldinig land for recreational purposes If()flh'l?'Oi7 ,'17 I . e.sst'xxtne,U I?epo;i: ( R Clumnba. Lq Igwlla 4  Summary Information on Project Cities Davao Cagayan de Oro Cotabato Calamba Dagupan Pop7ulatien (1990) 849.947 339.598 127.065 173.453 128.000 Housmg 163,329 47.724 21.581 32.109 21.219 Size of Central 1.000 heaares 400 hectares 120 becares 95 heaares 50 hecares Business Disstric (CBD) Morbidit rateper 595for 733fordiarrbea 3050fordiarrbea 8l8forparasilism 528forgastro- 10.000 from diarrhea(third rank (third ranik) (first rank) (secnd rank) entaeritis (third rank) diseases among diseases) Water bodies at Davao rivar and all Cagayan river and About 50% of dty Laguna Lake About 50% of city risk because of beaches close to adjoitnng beaches area cossiats of experiencing area are wetlands, municipal city not fit for cn Macajalar Bay wetlands. fNis ponds mcrease in turbidity used for fish wastewater recreational unfit for and estuarine area and rapid farming pullution pUlpOSeS recreational euirophicaticx ptuposes because of fecal contaminatimn The urban area/built-up areas in the project cities are characterized by a heavy con- centration of commercial and industrial activities. It is the area where population density is highest. These areas also represent the bulk of economic activity in the informal sector - such as, the production and consumption of raw and processed food, light manufacturing activities and retail distribution. A large proportion of piped water supply from the local Water District is also consumed in the Central Business District (CBD). Consequently, the pressure from both solid and liquid wastes in these areas greatly extceed the capability of the land and water resources to absorb. assimilate and recycle them. Calamba Impact During Construction Phase The implementation of the project and its components is projected to produce only minimal adverse environmenital impacts. The socio-economic impacts will be beneficial, and will result in a better standar-d of living for the municipalities and cities concerned. In the short-term, the project will provide emplovment and livelihood opportunities to the population of the surrounding communities through the jobs generated during the construction phase. In the long-term, better sanitary conditions will reduce sicknesses caused by water-related problems. Thuts an improvement of the existing environmental conditions is expected. The project N\ill und(lertake iitigatilig measures to minimize, or i at all possible, eliminate adverse impacts. hn vi riJnmentul . I "sevmnn/1f I?e'pu ni ( 1r[ Clcnnhc,, Ic'mci i  Air Quality. The implementation of the project will result in an increase in the ambient concentration of suspended particulates in the vicinity of the project site. This would be attributed to dust from land clearing and excavation activities, which expose soil to wind and vehicular traffic over unpaved road. Water Quality. Excavation activities in the project sites could also loosen soils and tiansport of these materials to any surface waters, thereby increasing siltation and turbidity. During the rainy season, surface runoff may increase total suspended solids, and cause temporary stress at the discharge points. However, the impact will be localized, and when the vegetative cover returns, impact on the receiving body of water caused by surface run- off will be eliminated. Noise. The noise impact during the construction stage is expected to be generally minimal and will not require any special noise abatement measare. The treatment plant sites shall have a setback away from residential clusters, which will definitely provide the necessary buffer to reduce noise impact during construction of the modified lagoon systems. During pipe-laying, some noise will be generated due to the construction activities and the temporary operation of heavy equipment. Noise from breaking concrete pavement and sidewalks may also pose a temporary problem. However, the noise level at the streets is expected to be within the ambient noise quality standards. Ecological Effects. As there are no rare. endemic species of flora and fauna in any of the project areas, project implementation has minimal impact on the terrestrial ecology. Vegetative covers are expected to be cleared, unavoidably, during civil works. Impacts During Opeiation Phase Air Quality. The operation of the wastewater treatment facility will have minimal impact on the air quality of the area. Aside from the occasional odor nuisance, it is not projected to have adverse effect at all. Water Qualitv. The implementation of the plroject will be beneficial to the general environment of participating cities and their environs. Discharging of untreated domestic waste water from the high volume consumers in each city's Central Business Districts into nearby bodies of water would thus be minimized or eliminated. However, operations and maintenance failures may result in occasional discharges. Socio-economic. The provision of sanitationi facilities in the project cities would undoubtedly benefit the general populace of these areas. The occurrence of epidemic- scale diseases caused by current unsanitary conditions will be reduced. This will result in a more healthy and productive population. .I:/?M l )e ,J / aIM/ . 1X%'e.Y.VM/e /?t IRep l:. ( 'a/atnha Ia;Kiina 6  Sludge Disposal. The recommended modified lagoon system or vertically integrated pond system of treatment will require sludge disposal at very infrequent intervals. The sludge in the anaerobic pond/s remains for an extended period continuously undergoing organic decomposition. This may take place over a 20-30 year period. One system in operation in the U.S. has not been desludged in thirty years. Recent testing of this system has indicated that the sludge is well-digested and very stable. If desludging does become due, arrangements can easily be made with the city environment office for disposal at the sanitary landfill. Mitigating measures to minimize, or if possible. eliminate adverse impacts will be implemented. Measures to enhance the existing environmental conditions in the project site shall be implemented to maintain the environmental sustainability of the area. The implementation of the project wil inevitably cause impacts, both adverse and beneficial. Table I shows the potential impacts, risks and the proposed mitigating actions. Enxn onmenral .-I.v. es.nnt ?Report. (alamha. Lagtwm  Table 1: Mitigation Actions Construction Phase Potential Impact & Risks Mitigation Action . Poor quality of construction * Design and supervision contract will be separated from supply and installation contract as a means of assuring quality of construction. Works engineers, with a relatively independent source of information on construction progress, will be hired. Air Pollution * Careful construction planning and work phasing, specifications and construction methods to reduce the length of time that the * Construction equipment and soil is exposed to the environment. vehicles may cause higher * Provision of adequately and properly maintained storage for suspended particulates, odors and construction materials and equipment. fumes emissions - CO2. CO, NOx * Expeditious and prompt removal of excavated materials or dredged spoils from construction sites. . Exposure of fine-grain particles to . Regular and adequate sprinkling of water on dust-generating wind and vehicular traffic will mounds/piles resulting from earthmoving activities and civil likely result in a decrease in air works. quality. . Good housekeeping for all construction affected areas and workplaces. . Control of motor vehicle and equipment emissions. * Use of protective gear by all workers. Water Pollution and Soil Erosion . Provide temporary drainage and storage facilities for excavation soils, for fuel and oils needed for equipment. * Siltation * Careful and rational planning of construction and post- construction phase_ of the project. . Maintenance of adequate drainage system. . Noise from operation of construc- . Erect temporary sound barriers around the work sites; avoid tion equipment would be about 70- si.nultaneous use of heavy equipment; limit daytime work, 80 dBA at 10 m: 50-70 dBA at 30 vehicle speed at 20 kph: regular maintenance of equipment m. . Use of appropriate mufflers and sound proofing of construction machinery, equipment. and engines. Use of appropriate shock- absorbing mountings for machinery. ,* Establishment of buffer zones and noise zones. * Temporary Disruption of Traffic * To the extent possible, feeder and collection sewer lines will be Flow located along secondary streets. * Scheduling and increasing input resources so that penod of traffic disruption in primary roads are reduced. * Coordinate with the local traffic management office and the PNP Traffic Management Command . Clear directional signs and barriers in case traffic rerouting is needed. . Public information campaign. _____onment_l_ I_sess_nent Repo_rt_( ____ __n_ j.  _________________ Operation Phasel Potential Impact & Risks Mitigation Action * Environmental hazards due to * Carefully designed post-construction maintenance. contingency accidents and man-made or natural and monitoring programs. disasters. * Well designed plan for detection of accident or natural events