Gandak Reaches Record 91.25 Metres, Breaching Embankments in Bihar and Uttar Pradesh

Synopsis

Heavy rain in the Gandak catchment caused the river to reach a record high of 91.25 metres on September 28-29, 35 cm more than in 2024. At two locations in West Champaran and one in Kushinagar, the embankments were damaged, leading to evacuation orders and night patrolling and relief camps. The Water Resources Department of Bihar states that 169 seepage points have been plugged along embankments and that water level at Valmikinagar barrage is on a downtrend.

The record in Nepal's part of the Gandak basin was broken by a brief, heavy rainfall.A brief bout of intense rain was enough to break a record in Nepal's section of the Gandak basin. The river had reached the new all-time high of 91.25 metres at the Bagaha level, which was 0.35 metres above the previous record of 90.90 metres, the Water Resources Department (WRD) in Bihar has said in a release.

By the night of 28th to 29th September, the embankments of Champaran on the left bank of the river were damaged at two places while the embankments of Kushinagar district in Uttar Pradesh on the right bank of the river were damaged at one place.

A Record level, not a Record discharge

The WRD had reported 5,43,500 cusecs discharge at the barrage of Valmikinagar at 6 am on September 28. It remained above the five lakh cusecs mark for 13 hours and above four lakh cusecs mark for 32 hours.

This marked a slight dip compared to the peak of 5,62,500 cusecs in 2024, but the rate at Bagaha was higher, the release said. The heavy rain on 26th and 27th September in West Champaran, East Champaran and Gopalganj had already raised the river level downstream of the barrage significantly.

The flood water was reported to have spread across West Champaran, East Champaran, Gopalganj, Saran, Muzaffarpur and Vaishali districts. The discharge was reduced to around 1.9 lakh cusecs by Tuesday morning.

Damage to the Embankments

The minor breach was found at chainage 4 km, near Khairtwa village, Bagaha-1 block on Monday evening, the WRD said in a statement. Agastiya, Khairtwa, Chandrapur villages were at risk of floods in low-lying areas and connectivity may be affected.

The site was approximately 3 km from NH 727, which was not anticipated to be impacted significantly as the flow in the river was receding. The embankment was also damaged in Phuliyakhad in Bairia block and 169 seepages points of the embankments were repaired during the night.

The Gandak is also called the Narayani on the Uttar Pradesh side. The embankment of the AP collapsed near Chain Patti in the Tatwa Tola area late Monday. Residents were evacuated and NDRF and SDRF teams deployed at the site by Chief Minister Yogi Adityanath. About 100 metres of embankment loss has been confirmed by the Chief Engineer of the Flood Division in Gorakhpur, who is referred to in the report as "Vikas".

Varying reports were received from residents regarding the extent. Ritesh Singh and Lalbagh Gupta estimated the impact of the flood on 12–13 villages as well as on at least 200 villages, respectively, and slammed the lack of maintenance work at the site. There have been no official confirmations of either of these numbers in the reports reviewed.

Relief and Response

Bihar Chief Minister Samrat Choudhary on Monday flew over Vaishali, Saran, East Champaran and Gopalganj districts to conduct aerial survey of the areas.

He held that the night watching of embankments was to be his responsibility, and that "no negligence" should be displayed in caring for the food and relief at camps and community kitchens. The embankments were under heavy pressure in all four of the areas where teams were deployed – Bagaha, Bettiah, Motihari and Gopalganj.

The Gandak's testing Bihar's embankments is a result of which?

The WRD says 68,800 sq km of Bihar's 94,163 sq km, or 73.06 per cent, is flood-affected. The catchments of the Kosi, Gandak, Burhi Gandak and Bagmati rivers are in the steep Himalayas.

The pattern is new. At least 177 people were killed in Nepal by flash floods caused by an ice-rock landslide at the end of August. Maharajganj and Kushinagar were put on high alert in Uttar Pradesh and all 36 gates of the Valmikinagar barrage were opened.

All 36 gates were opened in September 2024 as over 5.5 lakh cusecs were released from the same barrage by All India Radio.

What to Watch

No consolidated information on the number of villages or people affected is available in the reports reviewed. The immediate question is whether the affected sections are sealed off before the next rainfall and whether the inspections reveal any issues with the embankments, which residents of the Kushinagar Village have asked.

The embankment along the Gandak has a height of 91.25 metres at Bagaha, and it is now against this height that the next flood will be measured.