Ground Water Level Fluctuation

The occurrence of ground water generally depends upon the rainfall, drainage, topography and the geological conditions of the area. In Ganga basin according to India-WRIS database there are 2186 CGWB observation sites that has pre and post monsoon data. The pre monsoon data indicates that in north of river Ganga, Sub-Himalayan area of the basin, and in the north eastern part of the country generally the depth to water level varies from 2-5 meter below ground level. In major parts of Rajasthan depth to water level generally ranges from 10-40 m below ground level. Based on preand post monsoon data two interpolated maps, the ground water level fluctuation maps (recharge)-2011 and ground water level fluctuation maps (draft)-2011 are generated using inverse distance weighted interpolation technique.

 

Ground water fluctuation observed in the Ganga basin is assessed for recharge and draft conditions based on the available groundwater level in four different seasons. Groundwater recharge is estimated by the difference between the pre and post monsoon seasons. The ground water level fluctuation maps due to recharge-2011 shown in Map 18, in general there is a rise of ground water level due to recharge in the basin. The map shows in 2011, in Bihar Water level fluctuation data of recharge analysis shows that there is rise in water level between 2-4 m in entire state. Some of thedistricts of Bihar like Kaimur, Bhojpur, Patna, Nawada and Jamuai have shown rise in more than 4 m range. Only few wells analyzed are showing falls less than 2 meter in the water level in the districts of Madhubani, Supaul and Kishanganj of Bihar. The Chhattisgarh districts in the basin have shown a rise greater than 4m and in Surguja district a fall of water level less than 2m is seen in patches.

 

The Delhi has shown a varied pattern in the recharge of water level. Most of the areas have a fall of 2m in water level recharge with few locations having a fall in range of 2-4m and other parts have registered a rise of water level less than 2m. The fluctuation of water level in Haryana indicates that in general there is a rise and fall in water level with some districts like Sonepat and Gurgaon showing  a decline of greater than 4m in water level. In the districts of Jharkhand within the basin, there is an overall rise in water level in greater than 4m other than the district Hazaribagh there a small pocket of fall less than 2m in the water level recharge. In the districts of Madhya Pradesh comprising in the basin, there is an overall rise in water level in greater than 4m other than the district Sheopur and Morena there a small pocket of fall greater than 2m in the water level recharge.

 

The fluctuation of water level in Rajasthan indicated that there is both general decline and rise in water level. The Alwar, Bharatpur, Dausa, Dhaulpur, Karauli and Kota districts has shown a decline of water level recharge greater than 4m. The fluctuations of water level recharge in Uttar Pradesh indicate that there is in general rise in water level by a range of 2-4m other the Lalitpur district having a fall greater than 4m. Uttarakhand state is mainly covered by hilly/ mountainous areas and has no appreciable ground water potential other than the district Hardwar were water level less than 2m is observed. West Bengal observation wells are showing a rise in water level recharge greater than 4m other than Murshidabad district where the water level is noted with a fall greater than 4m.

 

Similarly, groundwater draft is estimated by the difference between successive post-monsoon (Rabi) seasons data. The ground water level fluctuation maps (draft)-2011 shown in Map 19, in general there is a fall of ground water in the basin. The map shows in 2011, in the districts of Chhattisgarh, Haryana, Himachal Pradesh and Jharkhand comprising in the basin, there is fall of water level by 2m in the water level draft. In Bihar Water level fluctuation data of draft analysis shows that in general there is fall and rise in water level in entire state. Only few wells analyzed are showing fall less than 2 meter in the water level in the Jamuai and Lakhisarai districts of Bihar.

 

The Delhi has shown a varied pattern in the draft of water level by both rise and fall in the level. Most of the areas have a fall of 2m in water level (recharge) with few locations having a fall less than 2m and other parts have registered a rise of water level in the range of 2-4m. The districts of Madhya Pradesh within the basin, there is an overall fall in water level in less than 2m other than the districts Bhopal, Guna, Indore, Sheopur and Ujjain there are pocket of fall greater than 4m in the water level draft. The fluctuation of water level in Rajasthan indicated that there is both general decline and rise in water level due to draft. The Bharatpur, Dausa, Dhaulpur, Karauli and Sawai Madhopur districts has shown a decline of water level (recharge) greater than 4m.

 

The fluctuations of water level (draft) in Uttar Pradesh indicate that there is in general fall in water level by a range of 2-4m. Also it is noted in some part of the state the water level due to draft has a rise in the range of 2-4m and the Lalitpur district having a rise greater than 4m. Uttarakhand state is mainly covered by hilly/ mountainous areas and has no appreciable ground water potential other than the district Hardwar where fluctuation in water level (draft) has shown a decline of less than 2m. West Bengal observation wells are matching with the general pattern of the basin with a decline of water level draft by less than 2m, except for Murshidabad, Birbhum district where the water level observed with a fall greater than 4m.

(Source: India-WRIS)