Luotian Reservoir, Yulin City, Guangxi Zhuang Autonomous Region

Luotian Reservoir has the function of annual regulation, focusing on irrigation, taking into account power generation, fish farming and flood control. The control basin area is 64 1 km2, of which the diversion basin area is 12. 1 km2. The original designed dam is 4 1.5m high and has a total storage capacity of 39.76 million cubic meters. The project started on 1958 and was completed and put into storage on 1960. 1976 for reinforcement and reconstruction, the main dam is raised by 1.5m, and the total storage capacity remains unchanged. In 2002, the reservoir was reinforced again, with new spillway tunnels and old culvert pipes.

The project consists of five parts: main dam, drainage pipe, spillway, flood diversion canal and hydropower station. ① The main dam is a homogeneous earth dam, with a dam length of 2 10. 1m, a dam crest width of 4m, and a breakwater height of 1.2m. ② The drainage pipe was originally located on the right side of the main dam, and it was a pressure pipe with an internal diameter of1.2m and a maximum displacement of1. 1969: The tunnel is used to draw water from the hydropower station, and the power generation tunnel is used as the irrigation and drainage tunnel, with the maximum diversion flow of12m3/s. In 2002, the original drainage culvert was filled and abandoned. ③ The spillway is located in a small ravine near Gubei Village, far from the main dam. It is an open wide-crested weir with a clear width of 4 1m and a maximum flood discharge of 616m3/s. Because the flood is not discharged from the original river, it will have an impact on the farmland in Gubei Village. ④ The glistening flood diversion canal was built in1978, with a diversion flow of 6 cubic meters per second, which can lead 12OO million cubic meters of water into the reservoir every year. The total length of the flood diversion canal is 4.2km, including tunnel1.5km, culvert 2.5km and open channel 200m. ⑤ A hydropower station behind the dam is set at the exit of the tunnel, with an installed capacity of 2× 1600 kW, completed in 1969, and an annual power generation of120,000 kWh.

Since the completion of the reservoir, the benefits have been remarkable: ① There are four main canals with a total length of 43.54 kilometers, and four branch canals with a total length of 26.86 kilometers and a total length of 70.4 kilometers, with an effective irrigation area of 2,734 hectares (4 1 10,000 mu). (2) The reservoir can hold 1 0,000-year flood, reduce the peak flow of10,000-year flood by 63%, protect 9,000 people and 600 hectares (9,000 mu) of cultivated land downstream, and ensure the safety of people's lives and property downstream. (3) The annual power generation of the power station behind the dam is about1.2000 kWh, and the power generation income is the main pillar of Luotian Reservoir. 65,438+0.54 hectares (2,365,438+0.6 mu) of fish farming area has been fully cultivated, and the comprehensive management of reservoirs has contributed to the local economic development.

Luotian Reservoir is located on Tang Chuan River, a tributary of Wanglao River, a tributary of Nanliu River. Tangchuan River originates from the southeast foothills of 60,000 mountainous areas. The highest elevation of the basin is about 1 1,000m. The total length of the river in the reservoir section above the dam head is 14.9 km, and the river gradient is 1.55%. The total rainwater collection area is 64. 1 km2, of which the rainwater collection area of this reservoir is 52 km2, and the rainwater collection area of imported river immersion cattle is 12. 1 km2. Average annual rainfall 1830mm, average annual runoff depth of 967mm, average annual flow 1.8 1 m3/ s, and average annual inflow of 62.74 million m3, including 56.78 million m3 in the reservoir and 5.96 million m3 outside. The reservoir area is characterized by low mountains and hills, and its geological distribution is Indosinian medium-coarse grained porphyry granite. Surface gullies and streams are well developed. Weathered overburden is shallow and primitive forest vegetation is good. In recent years, due to serious logging, some mountainous areas are bare and have poor vegetation coverage. The annual average temperature is 265,438 0.8℃, the extreme maximum temperature is 38℃, and the extreme minimum temperature is-2.65,438 0℃.

Luotian Reservoir has a designed irrigation area of 29 14 hectares (43,700 mu, some of which are duplicated with Jiangkou Reservoir) and an effective irrigation area of 2,734 hectares (4 1000 mu), making it the largest medium-sized reservoir in Yulin City. Construction started in September, 1958, and was stopped due to "big steelmaking" halfway, and was completed in May, 1960. During the construction of the warehouse, 334 households 1.337 people were relocated, and the cultivated land 144.3 hectares (2,654.38+0.65 mu) was flooded, and the relocation cost was 5 1.20 million yuan. The relocated households have 23 16 houses, and by August of 1973, 17 15 houses had been built; Install two diesel engines, two of which are * * *12kw; Construction of 1 bridge and 4 wooden boats. During the construction period, a relocation working group is responsible for relocation and resettlement. At that time, migrant workers built houses with bricks. The quality of mud bricks is very poor. Most migrant workers have never worked as bricklayers, and their construction skills are poor. The houses built soon became dangerous buildings, and they were all in a row, which did not meet the needs of the masses. Many relocated households have to rebuild their houses or move. 1968,330 people moved back to Tiaoma, Nakamura, Qingxin and Xinfa villages. The entrance of Luotian Reservoir is numerous and scattered, and it has been moved to 27 points in 7 villages (teams) such as Luotian, Shilong, Nakamura, Xinfa, Qingxin, Vaulting Horse and Kenzuo. At the time of relocation, paddy fields are 94 hectares (1.4 13 mu), sloping fields are 5.7 hectares (85 mu), and paddy fields are 0.07 hectares (65,438 mu) per capita. Due to the increase of population, by the end of 1990, the number of relocated households reached 60 1 and 3,066, the population increased by many times, and the per capita paddy field decreased to 0.03 hectare (0.46 mu). The lowest paddy field per capita is Gaoming Team in Shilong Village, 1 1,000 people own paddy fields. In recent years, the reform and relocation work has focused on supporting the development of production, and the production and living conditions of many relocated households have been appropriately improved.