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E801 V. 7 August 2003 THE SOCIALIST REPUBLIC OF VIET NAM MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT Public Disclosure Authorized CENTRAL PROJECT OFFICE ENVIRONMENTAL IMPAcT ASsESSMENT FOR VIET NAM WATER REsOURCES ASSISTANCE PROJECT Public Disclosure Authorized VOLUME 2: REPORT No. 6: DRAFT FINAL ENVIRONMENTAL IMPACT ASSESSMENT OF DA BAN SUB-PROJECT Public Disclosure Authorized PREPARED BY GEC GLOBAL ENVIRONMENTAL CONSULTANTS LTD. AND CENTER FOR BIOTECHNOLOGY FOR LIFE AND PRODUCTION Public Disclosure Authorized APRIL 2003 '7 THE SOCIALIST REPUBLIC OF ViET NAM MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT CENTRAL PROJECT OFFICE ENVIRONMENTAL IMPAcT ASSESSMENT FOR VMu NAM WATER REsoURCEs ASSISTANCE PROJECT VOLUME 2: REPORT NO. 6: DRAFT FINAL ENVIRONMENTAL IMPACT ASSESSMENT OF DA BAN SUB-PROJECT PREPARED BY GEC GLOBAL ENVIRONMENTAL CONSULTANTS LTD. AND CENTER FOR BIOTECHNOLOGY FOR LIFE AND PRODUCTION APRIL 2003 EXECUTIVE SUMMARY This report is a draft Environmental Impact Assessment for the Da Ban Sub-Project prepared as part of overall preparation of the Viet Nam Water Resources Assistance Project (VWRAP). This draft EIA was prepared with the configurations of the Da Ban Sub-Project as conceived, designed, and described in documents and information provide by the Consultant to the EIA Consultant as of 31 January 2003, supplemented by secondary data obtained by the EIA Consultant in documents, maps, interviews with local officials, and other similar sources, as well as a detailed socioeconomic survey conducted by the EIA Consultant in September 2002. This EIA has been prepared in accordance with the national legal, policy, and regulatory requirements for environmental management and protection in Viet Nam as well as the various relevant IDA operational safeguard policies. SUMMARY OF DA BAN SUB-PROJECT DESCRIPTION The Da Ban Sub-Project is located is located in Ninh Hoa District of Khanh Hoa Province on the south central coast of Viet Nam. The reservoir is located approximately 35 km north of Nha Trang, the provincial capital. The Da Ban River catchment is defined to the north by the Vong Phu Mountain Range (with peak elevations of 1,730 m), to the east by the Thong Nhat Railway line, and to the west by the Tan Lam River. The Da Ban River 2 is 37 km long and has a catchment area of 358 km . The Reservoir and headworks are located in Ninh Hoa District of Khanh Hoa Province, about 500 km north of Ho Chi Minh City. The Da Ban River converges with the Song Lot River and the combined river drains southward through Ninh Hoa District Town and discharges into Nha Phu Bay. The irrigation system includes two districts of Khanh Hoa Province: Ninh Hoa and Van Ninh. Additional beneficiaries include water supply for 60,000 people, some industrial plants, and water supply for aquaculture development of approximately 350 ha at present. The Da Ban Irrigation Scheme consists of: o An earth-fill dam with a crest elevation of 68.7 m; • A bottom discharge, reinforced concrete spillway with a design discharge of 538 m3/s; o Reinforced concrete outlet works with a design discharge of 12.0 m3/s; and o An irrigation scheme comprised of two primary canals - Tay and Dong - which diverge and traverse the land to the west and east of the Da Ban River. The secondary canal network consists of a number of canals, three major off-takes at the southern end of the Tay primary canal, and Ni to N4 canals being the off-takes from the Dong primary canal. The scheme was designed to irrigate an area of 7,800 ha and to supply water for industrial and domestic uses. In reality, service is only being delivered to 4,327 ha corresponding to an irrigation effectiveness of 55%. Most of earth works do not meet current design standards. There are cracks in the dam and seepage. In particular, the quality of joints of the inlet and the spillway are causing serious seepage. In addition, because of insufficient maintenance, engineering works have degraded rapidly and seriously in recent years, resulting in potential breakdowns of the Da Ban Dam, one of the highest dams in Viet Nam. Because of cracks that appeared in the body of the dam, MARD decreed that the water level in the reservoir should be lowered by 3 m to an elevation of 60 m instead of the normal water level at elevation of 63.00 m as per design. This reduced the capacity of the reservoir by 15 million m3 , equivalent to 20% of the total capacity, a significant reduction in water storage in this water-scarce area. If the water level of the reservoir had not been lowered in the 2001/2002 dry season, the Da Ban Reservoir could have supplied sufficient irrigation water for the 2002 summer-autumn crop to prevent the serious drought of that crop. Degradation, damage, and incomplete canal systems are causing a reduction in irrigation area, but also wasting of water at the head of canals, shortage, as well as unreliable delivery of irrigation water at the end of canals. The overall objectives of the Da Ban Sub-Project are to: o Preserve the available water in the Da Ban reservoir; o Upgrade the existing irrigation scheme; o Improve reliability, flexibility, and effectiveness of the irrigation system; o Reduce the cost of operation and maintenance; * Enable the scheme to satisfy all reasonable water needs by supplying a sufficient quantity of water at the required times of the year; and ii o Create the conditions for sustainable socioeconomic development using the application of modem design, engineering, and irnigation system management technologies. This will be achieved by modemization of technical infrastructure from the headworks to the farm fields and by modemization of the management system for the entire Irigation Scheme. The Da Ban Sub-Project will have a phased approach to modemization. This means that Da Ban Sub-Project investments will be grouped into two 'phases". The first phase will include the finalized dam safety review, rehabilitation works for the dams, rehabilitation works for main and primary canals and rehabilitation works and modernization for two pilot areas representing about 20% of the command area. The second phase will include expanding the experiences gained through pilot testing to remaining 80% of the command area. MAIN CONCLUSIONS OF IMPACT ASSESSMENT The Da Ban Sub-Project is environmentally feasible. The Sub-Project will have a number of significant positive benefits: o Increase in beneficiary income and reduction of poverty throughout the command area through improved and reliable water supply for agricultural production; and o Increases in employment and labor in a region with very high levels of unemployment and underemployment. All of the potentially significant environmental impacts identified in the impact assessment can be mitigated and they are described below. These conclusions apply to both packages of investments for the Da Ban Sub-Project. At this time, it is concluded that no separate environmental assessment is required for the second package of investments. DA BAN SUB-PROJECT ENVIRONMENTAL MANAGEMENT PLAN The Environmental Management Plan for the Da Ban Sub-Project consists of an environmental mitigation program and an environmental monitoring program. The environmental mitigation program consists of: • Proper management and disposal of dredged and excavated soils to minimize degradation of water quality; o Proper environmental management of construction worker camps, including minimization of disruption to local residents from construction activities to limit localized environmental degradations and disturbance to local communities; o Implementation of a comprehensive resettlement and compensation action plan; o Environmental review of provincial aquaculture program and implementation of environmental action plan to mitigate incremental effects of incremental coastal aquaculture that arises as a result of the Sub-Project o Maximization of employment opportunities for local residents to take full benefit of the employment opportunities created by the Sub-Project; * Implementation of a Emergency Preparedness Plan for managing Da Ban Dam flood safety risk; o Prevention of disruption to designated cultural and historical sites; and o Extension of the local provincial program for IPM to command area beneficiaries to prevent possible degradation of aquatic resources from increased use of fertilizer and pesticides. An important environmental mitigation will be the minimization of disruption to water users during canal lining. Improper timing of the construction activities associated with canal reinforcement will negatively affect water supply to farmers downstream. On the one hand, construction of canal reinforcements in the dry season can proceed very quickly, but water supply needs to be turned off during the construction periods; the dry season is the season when water supply via the irrigation scheme is most critical. On the other hand, water supply to the farmers via the irrigation scheme is not as critical in the rainy season and yet construction is much more problematic and expensive given the larger amounts of water in the system at that time. It will be necessary to develop rigid construction timetables for main and primary canal reinforcement to minimize disruption to the beneficiaries and at the same time have efficient implementation of this part of the Sub-Project. In addition, consultation with all affected parties will be required in order to reach agreement on exactly how canal lining will proceed. The recommended environmental monitoring activities are: o Compliance monitoring of the environmental mitigation program; e Surface and groundwater quality monitoring program to assess incremental effects of sedimentation, erosion, and fertilizer and pesticide use; o Effects monitoring for effectiveness of coastal aquaculture mitigation program The total cost of the Da Ban Sub-Project Environmental Management Plan is US $189,826, consisting of US $99,706 for the environmental mitigation program and US $90,120 for the environmental monitoring monitoring programs. INSTITUTIONS RESPONSIBLE FOR IMPLEMENTING THE DA BAN EMP The Da Ban EMP will be implemented within a comprehensive organizational framework under the overall VWRAP Project.