2.2　Surface Water Resources

Quantity of surface water resources refers to the annual renewed quantity of surface water in rivers, lakes and glaciers, i.e., annual quantity of natural river runoff formed by local precipitation. The quantity of surface water resources in China was 2,626.39 billion m3 in 2014, equivalent to 277.4 mm in depth, which was 1.7% less than normal and 2.3% less than that in 2013.

The quantity of surface water resources in the Northern Six Regions in 2014 was 381.08 billion m3, equivalent to 62.9 mm in depth, 13.0% less than normal and 31.1% less than that in 2013. That in the Southern Four Regions was 2,245.31 billion m3, equivalent to 657.9 mm in depth, 0.6% more than normal and 5.1% more than that in 2013. Among the ten Class I WRRs, the Southeast Rivers and Songhua had an annual quantity 11.4% and 8.5% more than normal, respectively; the Yangtze and Pearl had an annual quantity 1.7% and 1.3% more than normal, respectively; and all other regions had an annual quantity less than normal, in which the Liaohe, Haihe and Huaihe had an annual quantity 59.1%, 54.6% and 24.7% less than normal, respectively. Compared with 2013, the Southeast Rivers, Yangtze and Huaihe experienced an increase of surface water resources of 13.0%-16.2% and the Southwest Rivers experienced a small increase; and all the other regions experienced decrease of surface water resources, in which the Liaohe, Haihe and Songhua experienced decreases of 69.0%, 44.4% and 42.8%, respectively. See Table 3 and Figure 6 for comparison of the 2014 annual natural runoff with the 2013 annual natural runoff and normal by Class I WRR.

Table 3 Comparison of 2014 natural runoff with 2013 natural runoff and normal by Class I WRR

Figure 6 Comparison of 2014 natural runoff with normal by Class I WRR

Note: The Yangtze includes the Taihu Lake Basin.

In 2014, East China had 502.29 billion m3 of surface water resources, which was equivalent to 471.3 mm in depth and 3.1% less than normal; Central China had 631.16 billion m3, equivalent to 378.3 mm in depth and almost equal to normal; and West China had 1,492.94 billion m3, equivalent to 221.7 mm in depth and 1.9% less than normal. Among the 31 PARs, 14 had a quantity of surface water resources more than normal, in which Shanghai had a quantity 64.7% more than normal; and 17 had a quantity less than normal, in which Beijing, Shandong, Hebei, Liaoning and Henan had a quantity over 40% less than normal. Table 4 and Figure 7 show comparison of the 2014 natural runoff with the 2013 natural runoff and normal by PAR.

In 2014, 18.70 billion m3 of water flowed from abroad into China; 538.69 billion m3 of water flowed from China to abroad; and 121.78 billion m3 of water flowed from China into the border rivers between China and other countries.

In the whole country, the total quantity of water flowing into the sea in 2014 was 1,632.97 billion m3, or 72.33 billion m3 more than that in 2013, in which 6.99 billion m3 was from the Liaohe, 2.04 billion m3 from the Haihe, 10.86 billion m3 from the Yellow, 36.48 billion m3 from the Huaihe, 925.00 billion m3 from the Yangtze, 207.39 billion m3 from the Southeast Rivers, and 444.21 billion m3 from the Pearl. Water flowing into the sea accounted for about 40% of the quantity of local surface water resources in the Liaohe, 70% in the Huaihe and over 90% in the Pearl, Yangtze and Southeast Rivers.

Table 4 Comparison of 2014 natural runoff with 2013 natural runoff and normal by PAR

Figure 7 Comparison of 2014 natural runoff with normal by PAR