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E1114 v 8 Public Disclosure Authorized WORLD BANK FUNDED CHINA IRRIGATED AGRICULTURE INTENSIFICATION III PROJECT DAM SAFETY REPORT Public Disclosure Authorized Public Disclosure Authorized PREPARED BY STATE OFFICE OF COMPREHENSIVE AGRICULTURAL DEVELOPMENT JANUARY 2005 Public Disclosure Authorized Table of Contents 1. Description of the dams in the project areas 2. Main problems of the 4 dangerous dams and the remedy arrangement 3. Operation of the safe dams and conclusions from their safety inspection 4. Safety control of the dams 5. Summary of the major specifications of the dams 6. Monitoring and reporting systems on dam safety 1. Description of the dams in the project areas There exist 17 dams higher than 15 meters in the 5 project provinces, which supply irrigation water to the project areas. Of which the large sized dams with a water storage capacity each of more than 100 million cubic meters account for 10 and the others are medium sized dams with a water storage capacity ranging from 10 million to 100 million cubic meters each. The 17 dams are allocated as 8 in Anhui Province, 4 in Henan Province, 3 in Shandong Province and 2 in Jiangsu Province. The 5 provincial authorities involved in the project have conducted overall inspection and safety appraisal on the 17 dams in line with the Bank’s operational handbook of “Dam Safety” (OP 4.37) and the “Rule on Appraisal of the Dam Safety” issued by the Ministry of Water Resources in 1995. The inspection mainly covers the safety situation of the dams and their installed structures such as the gates and spillways. The safety appraisal largely covers, based on the verification of the recording data of water regulation, safety inspection, repairing and maintenance, daily care and site observation, re-examination of the criterion on flood control and evaluation on anti-seismic stability, structural stability and seepage stability in accordance with the “Rule on Appraisal of the Dam Safety”. Results from the safety inspection and appraisal reveal that 4 dams from among the 17 dams involved in the project areas have safety problems including inadequate flood control capacity, anti-seismic stability or structural stability. The 4 dams are: the Xiaotashan Dam and Shilianghe Dam in Lianyungang Municipality, Jiangsu Province, the Fenshuiling Dam in Mingguang City, Anhui Province and the Gutou Dam in Changqing District of Jinan Municipality, Shandong Province. The other dams are safe and in normal operation. 2. Main problems of the 4 dangerous dams and the remedy arrangement 1) Xiaotashan Dam in Lianyungang Municipality, Jiangsu Province: The dam has the major problems of inadequate flood control capacity, inadequate spillways, lacking of anti-seismic design, and overall cracking of the spillway gate at the main dam and irrational layout of energy absorption at its down stream. The planned remedies include: reconsolidation of the main dam and the east and west auxiliary dams in terms of flood control and anti-seismic capacities, reconstruction of the spillway gate at the main dam, reconstruction of the cracking part of the main dam, building a river cross dam at 350 meters down to the east sluice gate, and harnessing the Qingjiang River at the down stream of the reservoir. The rehabilitation works commenced on October 17, 2002 and was planned to be completed in 30 months by May 30, 2005. Up to date, the main works is almost completed. Its quality has been proven to be in conformity of the rated standard through examination and acceptance. Through test by the last flood season, the dam proves to have adequate flood control and water storage capacities up to the designed standard of one incidence every 100 years. 2) Shilianghe Dam in Lianyungang Municipality, Jiangsu Province: The dam was listed as the potentially dangerous dam by the Ministry of Water Resources in 1992 in its “Circulation on Nationwide Reconsolidation of the Second Group of Key Dangerous Dams” (Shuiguan[1992] No.5). The reconsolidation argumentation report was endorsed by the Huihe River Water Resource Committee of the Ministry of Water Resources in May 1998. The reconsolidation feasibility study report was endorsed by the Planning and Economic Commission of the Jiangsu Provincial Government by its official document of Sujijingnongfa (1998) No.1389 in August 1998. The rehabilitation was then designed and approved by the Huihe River Water Resource Committee by its official document of “Approval of the Preliminary Design on Reconsolidation of the Shilianghe Dam” (Huiweiguiji [1998] No 123) in December 18, 1998. To relieve the sluice pressure of the spillway gate of the dam, the Ministry of Water Resources also approved the sluice enlargement works (Shuiguiji [1999] No 240) in addition to reconsolidation of the main and auxiliary dams. The reconsolidation works commenced on January 13, 1999. Reconsolidation of the original sluice gate was completed and preliminarily accepted in December 2000. Reconsolidation of the main and auxiliary dams commenced in November 1999 and was completed and accepted in September 2003. Sluice enlargement works commenced on May 18, 1999 and was completed and accepted in June 2002. By completion of all the individual reconsolidation works, the dam has been kept in normal operation without emergence of any safety risks. 3). Fenshuiling Dam in Mingguang City, Anhui Province: The safety appraisal carried out by the Dam Supervision and Testing Center of the Ministry of Water Resources in March 2002 listed the dam as the “dam of category 3”, i.e. the dangerous dam needed to be reconsolidated. In that year, the Water Resource Bureau of the Chuzhou Municipality submitted its report of “the Preliminary Design of Reconsolidation of Fenshuiling Dam in Mingguang City” (Shuiji [2002] No 75) and was approved by the Department of Water Resources of Anhui Province (Wanshuiji[2002] No 506). Total cost of the reconsolidation accounted for RMB. 20.02 million Yuan. Reconsolidation commenced in February 2004 and is still under way, mainly including reconsolidation of the main dam and spillway, and membrane covering on the earth works of the dam. It was planned that the main works was to be completed by the end of 2004. The key works to ensure the normal and safe operation of the dam has been completed and the quality is good enough to satisfy the Bank. Up to date, the dam is able to provide reliable water supply to the project. By completion of all the works, the dam will be safer and more reliable. 4) Gutou Dam in Changqing District of Jinan Municipality, Shandong Province: In 2002, the Planning Commission of Shandong Province issued its document of “Approval of the Feasibility Study Report on Reconsolidation of Gutou Dam in Changqing District of Jinan Municipality” (Lujinongjing [2002] No 123) and clarified the endorsement of the reconsolidation of the dam with a total cost of RMB. 39 million Yuan. The rehabilitation design was approved by the Shandong Provincial Department of Water Resources with its official documents of “Approval of the Preliminary Design of Reconsolidation of Gutou Dam in Changqing District” (Lushuiguiji [2002] No 28) and “Approval of the Drawing Design of Reconsolidation of Gutou Dam in Changqing District (Lushuikan [2002] No 64). Reconsolidation of the dam commenced on February 18, 2003 and was completed in October 2004. However, the works has not been officially examined and accepted yet. The dam is now under normal and good operation without emergence of any safety risks. 3. Operation of the safe dams and conclusions from their safety inspection 1). Luhun Dam in Henan Province: The dam was completed in 1965 and reconsolidated and raised height in 1974, 1975, 1976 and 1986 respectively. At present, the dam has a sound monitoring system to detect its operation. Based on the analysis of the data from yearly operation and observation, the dam is now in normal operation and the key works of the dam is under operation up to the designed standard. 2). Suyahu Dam in Henan Province: The dam was completed in 1958 and subsequently reconsolidated by 5 times up to 1990. At present, the dam has a quite sound monitoring system to detect its operation. Based on the analysis of the data from yearly operation and observation, the dam is now in normal operation and the key works of the dam is under operation up to the designed standard. 3). Nanwan Dam in Henan Province: The dam was completed in 1956 and subsequently reconsolidated and raised height in 1957, 1969, 1971, 1974 and 1978. At present, the dam has a quite sound monitoring system to detect its operation. Based on the analysis of the data from yearly operation and observation, the dam is now in normal operation and the key works of the dam is under operation up to the designed standard. 4). Yahekou Dam in Henan Province: The dam was completed in 1968 and reconsolidated after the severe flood in August 1975 and rehabilitated in 1988. At present, the dam has a quite sound monitoring system to detect its operation. Based on the analysis of the data from yearly operation and observation, the dam is now in normal operation and the key works of the dam is under operation up to the designed standard. 5. Qiangchuan Dam in Shandong Province: The dam was constructed in 1959 and completed in 1960. According to the “Guideline on Dam Safety Evaluation” (SL258- 2000) and the data supplied by the Registration Form of the dam, analysis proves that the dam is of “category A” in terms of its safety and the dam is classified as of “category 1”. The dam is good enough in terms of its quality and operational management and can be operated according to its designed standard. 6. Bashan Dam in Shandong Province: The main works was completed in December 1993 and reconsolidated by July 2001.