Patna: Groundwater levels in Patna Sadar block have declined sharply over the past year, raising concerns among environmental experts and officials over the long-term impact of rapid urbanisation and unchecked concrete expansion in Bihar’s capital.
According to data from the Public Health Engineering Department (PHED), the groundwater level in Patna Sadar stood at 20.9 feet on May 15, 2025. By May 15, 2026, it had dropped to 25.9 feet — a decline of approximately five feet within a year.
Officials Blame Expanding Concrete Sprawl
PHED officials said the city’s extensive concrete coverage was preventing rainwater from naturally recharging groundwater reserves.
According to officials, groundwater recharge typically takes place through:
- Rainwater seepage
- Rivers
- Ponds and water bodies
However, in Patna city, most rainwater now flows directly into drainage and sewer systems instead of percolating into the soil.
Officials warned that continued urban expansion in areas such as Patna and Danapur was worsening the situation.
Several Urban Blocks Witness Decline
Apart from Patna Sadar, groundwater levels also deteriorated in several other blocks, including:
- Danapur
- Maner
- Bakhtiyarpur
- Mokama
- Pandarak
Recorded declines included:
| Block | May 2025 | May 2026 |
|---|---|---|
| Bakhtiyarpur | 24.5 ft | 26.5 ft |
| Mokama | 24.3 ft | 29.7 ft |
| Pandarak | 23.8 ft | 29.6 ft |
| Danapur | 21.9 ft | 25.6 ft |
| Maner | 22.3 ft | 26.4 ft |
Some Rural Blocks Show Improvement
Despite declining levels in urban regions, several rural and semi-rural blocks recorded improved groundwater conditions compared with last year.
Officials reported improvements ranging from one to nine feet in blocks such as:
- Barh
- Belchhi
- Fatuha
- Khusrupur
- Athmalgola
- Ghoswari
- Phulwari
- Masaurhi
- Naubatpur
Other blocks showing significant improvement included:
| Block | Improvement |
|---|---|
| Dhanarua | Up by 9.5 ft |
| Daniyawan | Up by 9.5 ft |
| Sampatchak | Up by 7.9 ft |
| Bikram | Up by 7.9 ft |
| Dulhin Bazar | Up by 7.0 ft |
| Punpun | Up by 6.6 ft |
| Bihta | Up by 6.4 ft |
| Paliganj | Up by 4.4 ft |
Experts Call for Dedicated Groundwater Policy
A Patna-based water expert said Bihar lacked comprehensive data regarding groundwater extraction and recharge rates in Patna.
He warned that expanding urban construction was severely affecting natural recharge mechanisms.
“No one possesses precise data regarding the extent of groundwater extraction taking place in Patna city,” he said.
He called for:
- A dedicated groundwater research department
- Scientific assessment of groundwater reserves
- Monitoring of extraction and recharge rates
- A long-term government policy on groundwater conservation
Concerns Over Future Water Security
Environmental experts warned that continued depletion of groundwater could pose serious risks to urban water security in the coming years.
They said increasing concretisation, shrinking ponds and inadequate rainwater harvesting systems were emerging as major challenges for rapidly expanding urban centres such as Patna.
