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โครงการหนังสืออิเล็กทรอนิกส์ด้านการเกษตร เฉลิมพระเกียรติพระบาทสมเด็จพระเจ้าอยู่หัว

7.1.1.4 Water demand for domestic use

Water demand for domestic use is assessed based on the population living in a
community. Table 7.4 shows the estimated water requirements of households based on the

standard practice for investigation of basic minimum needs classified by four types of communities.

Table 7.4 Water requirement of households (RID, 2011)

Communities Water consumption (litre/person/day)
City municipality 250

Town municipality 200
Commune municipality 120

Out of municipality 50

7.1.2 Estimation of water resource availability

Thailand’s average annual rainfall is around 1,500-1,700 mm ranging from 1,200 mm in the

North and the Central plains to 2,100-2,300 mm in the Western part of the South and the Eastern
part of the country. According to the rainfall statistics by provinces during 2002-2011, the average

annual rainfall of about 1,710 mm was calculated and the total volume of water from rainfall was
3
around 728,000-800,000 million m . Table 7.5 shows the numbers of large and medium reservoirs
in each water basin and their storages and in the Appendix I installed cover all basins. The stored
water in those reservoirs will become the water supply source for irrigation and waterworks. The

numbers of reservoirs are referred to the irrigated water projects under Royal Irrigation Department
and other governmental agencies and classified into large, medium, and small scale projects,

electrical water pump project, and detention storage project (known as “Kaem Ling Project”).
Hence, based on the stored water in reservoirs and the average annual rainfall data, the total

water availability can be roughly estimated and the results are shown in Table 7.6.

Table 7.5 Numbers of large and medium reservoirs classified by 25 watersheds

Large and Medium Projects Total Projects

Stored Irrigated Stored Irrigated Command
Watersheds No. of water areas No. of water areas areas
projects projects
3
3
(M. m ) (rai) (M. m ) (rai) (rai)
Salawin 16 13.8 41,260 343 24.70 93,506 114,262
Kok 8 73 276,200 213 96.88 331,470 262,675
Ping 57 14,122.5 2,137,041 1,172 697.60 2,002,071 1,277,528

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