• Groundwater exploitation and utilization
The 92.39 m deep well, drilled in the center of the Dachaidan alluvial fan, is used
for urban water supply for nearby towns. It is supported by the Dachaidan Water
Utitlities Corporation and the current groundwater mining volume is 4000 m
3 /d.
(c) Meteorological and hydrological conditions
• Climate and hydrology
– Climate
The study area is deeply inland and located on the plateau. It is subject to plateau
climate characterized by cold winters, cool summers, large temperature differences
between day and night, small humidity and precipitation, fast wind speed and many
dust storms. According to the 1971–2010 data from Dachaidan weather station
(Table 5.37), the mean annual temperature is 2.4 °C. The maximum temperature
reaches 13.5–16.2 °C, mainly seen in June to August, while the minimum can be
down to −17.5 °C (in January 1978). The temperature remains negative from
November to next March. With an annual average of 92.9 mm, 76.6% of the
precipitation occurs in May to August during the year. The average annual evaporation is 2167.1 mm and the moisture coefficient is 0.043, which denotes arid
climate (Fig. 5.14).
– Hydrology
Rivers in the study area are mostly seasonal rivers. Among them, the Baligou River
is a larger river affected by the seasons, and it consists of the perennial section
above the mountain pass and the seasonal section below. The perennial Reshuigou
River also has relatively stable flow and recharges hot springs.
Baligou River: Originating from the Qaidam Mountain, the river is made up of
ice and snow melt water and bedrock fissure water. The 27.36 km long river
(excluding the Quanji River) has a drainage area of 460.37 km
2 above the mountain
pass. There is large interannual change in the flow due to seasonal variations
(Fig. 5.15). The runoff within 1–2 km from the river outlet all infiltrates and
replenishes groundwater, and the average annual flow is 0.324 m
3 /s. The HCO 3 Á
Cl–Ca Á Na type water has a salinity of 0.26–0.96 g/L.
At the month of the river, an artificial dam and two diversion channels with a
total length of about 8.5 km have been built in order to divert water for greening
Dachaidan Town. According to the survey, the water is diverted for 150 days from
May to September every year. The old and new channels support average water
diversion of 0.014 and 0.029 m
3 /s respectively, making a total of 0.043 m
3 /s
(3715.2 m
3 /d).
Reshuigou River: Originating from Chaidamu Mountain, the river is mainly
comprised of ice and snow melt water and precipitation, followed by bedrock
fissure water. The 11.4 km long seasonal river drains an area of 29.6 km
2 . It is
150
5 Application Cases
The 92.39 m deep well, drilled in the center of the Dachaidan alluvial fan, is used
for urban water supply for nearby towns. It is supported by the Dachaidan Water
Utitlities Corporation and the current groundwater mining volume is 4000 m
3 /d.
(c) Meteorological and hydrological conditions
• Climate and hydrology
– Climate
The study area is deeply inland and located on the plateau. It is subject to plateau
climate characterized by cold winters, cool summers, large temperature differences
between day and night, small humidity and precipitation, fast wind speed and many
dust storms. According to the 1971–2010 data from Dachaidan weather station
(Table 5.37), the mean annual temperature is 2.4 °C. The maximum temperature
reaches 13.5–16.2 °C, mainly seen in June to August, while the minimum can be
down to −17.5 °C (in January 1978). The temperature remains negative from
November to next March. With an annual average of 92.9 mm, 76.6% of the
precipitation occurs in May to August during the year. The average annual evaporation is 2167.1 mm and the moisture coefficient is 0.043, which denotes arid
climate (Fig. 5.14).
– Hydrology
Rivers in the study area are mostly seasonal rivers. Among them, the Baligou River
is a larger river affected by the seasons, and it consists of the perennial section
above the mountain pass and the seasonal section below. The perennial Reshuigou
River also has relatively stable flow and recharges hot springs.
Baligou River: Originating from the Qaidam Mountain, the river is made up of
ice and snow melt water and bedrock fissure water. The 27.36 km long river
(excluding the Quanji River) has a drainage area of 460.37 km
2 above the mountain
pass. There is large interannual change in the flow due to seasonal variations
(Fig. 5.15). The runoff within 1–2 km from the river outlet all infiltrates and
replenishes groundwater, and the average annual flow is 0.324 m
3 /s. The HCO 3 Á
Cl–Ca Á Na type water has a salinity of 0.26–0.96 g/L.
At the month of the river, an artificial dam and two diversion channels with a
total length of about 8.5 km have been built in order to divert water for greening
Dachaidan Town. According to the survey, the water is diverted for 150 days from
May to September every year. The old and new channels support average water
diversion of 0.014 and 0.029 m
3 /s respectively, making a total of 0.043 m
3 /s
(3715.2 m
3 /d).
Reshuigou River: Originating from Chaidamu Mountain, the river is mainly
comprised of ice and snow melt water and precipitation, followed by bedrock
fissure water. The 11.4 km long seasonal river drains an area of 29.6 km
2 . It is
150
5 Application Cases