Bihar warns against eating fish washed in from Nepal floods

The advisory comes after flash floods in Nepal caused waters from the Trishuli River to flow into Bihar through the Gandak and Kosi rivers.

As water levels rose, unfamiliar fish began appearing in flood-affected areas, with some people reportedly falling ill after consuming them.

Government issues fish advisory

The Animal and Fisheries Resources Department has urged people to avoid fish caught directly from floodwaters, warning that they could be contaminated with sewage, bacteria, viruses and other pathogens.

Nepal Police has also issued a similar warning to residents.

According to the advisory issued by Bihar's Department of Dairy, Fisheries and Animal Resources, floods can force fish out of ponds, rivers, lakes and reservoirs, allowing them to spread across large areas with the floodwaters.

The department said prolonged exposure to polluted drains, dead animals and other contaminants can make such fish unsafe for consumption. People have been advised to avoid eating fish caught from floodwaters until environmental conditions stabilise.

What authorities have asked people to do

The department has issued several precautionary measures:

• Do not consume unknown or unusual-looking fish.
• Avoid buying, selling or consuming fish caught from floodwaters.
• Do not assume unfamiliar fish are safe to eat without verification from the concerned department.
• Seek immediate medical attention if vomiting, diarrhoea, abdominal pain, dizziness or breathing difficulties develop after eating such fish.
• Report sightings of unusual fish to the local District Fisheries Officer or administration.
• Avoid rumours and do not consume unknown fish for the sake of safety.

Floodwaters carry debris, dead fish and wreckage

The Kosi and Gandak rivers, both fed by waters originating in Nepal, have swelled following the flash floods and are carrying large amounts of debris, including dead fish.

Landslides and glacial bursts in Nepal's hilly regions have washed silt, mud, stones and large tree trunks downstream.

Wreckage from collapsed bridges and damaged hydroelectric projects, along with vehicles, household items and LPG cylinders from flooded villages, has also been reported in Bihar's rivers.

Human and animal remains washed down from Nepal have further heightened concerns over contamination and the spread of infections.

Health risks rise as contaminated water spreads

Health experts have warned that contaminated floodwater mixing with drinking water sources such as hand pumps and wells could trigger outbreaks of diarrhoea and cholera.

Consumption of contaminated water and food can also increase the risk of typhoid, while hepatitis A and E can spread through contaminated water.

Stagnant water and prolonged waterlogging are meanwhile expected to create breeding grounds for mosquitoes, increasing the risk of dengue, malaria and chikungunya, along with skin and eye infections.

Arsenic, iron add to Bihar's water worries

The situation is further complicated by existing groundwater contamination in several districts bordering Nepal, including West Champaran, East Champaran, Sitamarhi, Kishanganj, Purnia and Araria.

The groundwater in these districts already contains arsenic levels above the safe limit of 10 ppb.

Arsenic concentrations are particularly high in districts along the Ganga, although notable levels have also been detected in floodplains formed by rivers originating in Nepal.

High iron content has also been recorded in water across nearly all seven districts bordering Nepal. Kishanganj has reported levels several times higher than normal.

Officials have warned that iron carried by the floodwaters could further worsen contamination in local water sources.

Floods threaten farmland, food supply

The floodwaters are also expected to affect farmland across Bihar's border districts, raising concerns over a possible shortage of grains and vegetables and adding to the challenges faced by farmers.

Speaking to NDTV, Dr PV Singh of LNJP Hospital under the Bihar government said authorities need to relocate residents of affected areas to safer locations in a timely manner to protect them from the health risks posed by contaminated water.

He described diseases linked to the polluted floodwater as a serious threat to people's lives.

Authorities have urged residents in flood-hit districts to remain alert, avoid contact with floodwater wherever possible and follow official advisories until river levels stabilise and affected water sources return to normal.