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Water resources
( 2003-08-24 15:32)

Ningxia is the region, which has limited water resource even though there are rainfall, surface water or underground water. As to the water resource distribution, it is quite uneven between northern and southern parts. The total amount of water resources of Ningxia is 1.05 billion m3 (excluding repeated estimation). Among them: the surface water is 889 million m3, and the groundwater is 2.657 billion m3 (including the repeated estimation). Besides, the runoff of the Yellow River in Ningxia is 32.5 billion m3, and 4.0 billion m3 can be utilized. Theoretical hydro-energy is 1.955 million kW. The distribution of the water resources is uneven. Most of them are distributed in the north, i.e. the Yellow River irrigated area. The shortage of water reserve in the central highland and hilly area make the drought the most severe problem in the whole Region. Most of them are of salted water lying deep underground. It is hardly worth using for irrigation. In the semi-droughty and semi-wet mountainous area in the south, the river network has a moderate coverage. There are Qingshi River, Kushui River, Hulu River, Jing River and Zuli River. Although there are plentiful water reserves, only small proportion can be used..

Surface water resource

The annual average runoff of the surface water is 889 million m3 (the runoff of the Yellow River major stream excluded). The runoff of the Yellow River is 32.5 billion m3. These two together is of a favorable condition for agricultural production. As early as 2,000 years ago (during the Qin and Han dynasty), people began to draw water from the Yellow River for irrigation. An area called "Hetao irrigated area" was formed then. In this area, there are irrigating channels as Tanglai Qu canal, Hanyan Qu, Qin Qu, Han Qu, Huinong Qu, and Xigan Qu, total 14 major canals. Their total length is 1397 km and has the capacity of 744 m3/s in flow, about 7 million m3 per year. Its irrigated area add up to as large as 275,000 ha.

Underground Water Resource

The amount of underground water resource is about 2.657 billion m3. But itsdistribution is quite uneven. The south and plains of north possess much more ground water than the loess hilly area. For example, Yinchuan and Weining plain occupy only 13% of the total area of the whole Region, but it has 63.85% of the total underground water reserves. The loess hilly land of Lingwu and Yanchi occupy 69% of the total area, but their ground water is only 16.2%.

Hydro Power

Theoretical reserves of hydro energy in Ningxia are 1.955 million kW. Among these, Erlonghe River major stream accounts for 1.9297 million kW, about 98.7% of the total. The branches of the Yellow River have 253,000 kW, only 1.3% of the total. Most of the water power resources are concentrated in the valleys of The Yellow River major stream, while some are located at the east side of Liupanshan Mountain. There are places that have the possibility to use the hydraulic power. The estimated installed capacity is 1.974 million kW. The ensured capacity is 752,000 kW. The total sum of energy obtained per year can reach 8.04 billion kWh. There are three places with an installed capacity over 10,000 kW. All of them are located on the Yellow River major stream, i.e. Daliushu, Shapotou and Qingtongxia. The Daliushu hydro power station has a capacity of 1.6 million kWh, 7.2 billion kWh per year. There are nine places having an installed capacity of 5,000 ~ 10,000 kW. Among them, eight are located at the Jing River system, and one is located at Qixing Qu of Zhongning County.

   
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