BUCHAREST, Feb. 6 (Xinhua) -- Romania's National Institute of Hydrology and Water Management (INHGA) issued a red flood alert on Friday for the Niscov River in Prahova and Buzau counties, warning of dangerous rises in water levels following heavy rainfall.

A drone view shows a flooded area, after heavy rain triggered flooding in Slobozia Conachi, Galati country, Romania, September 14, 2024. (File photo: Reuters)

The alert is valid until 3 p.m. local time (1300 GMT) and signals a possible exceedance of danger thresholds.

Authorities also issued an orange alert until 12 p.m. local time for the Teleajen River in Prahova County and for rivers in the Milcov basin in Vrancea County. A yellow alert is in effect for parts of the Barlad River basin in eastern Romania.

Romania's hydrological authorities classify flood warnings into three levels - yellow, orange and red - ranging from potential flooding risk to extreme danger.

Emergency alerts were sent to residents in at-risk communities. In Prahova County, firefighters responded to several calls to pump water from flooded yards, with no homes reported damaged.

In Buzau County, rising water levels on the Niscov River blocked road access to the village of Mierea, leaving 12 people isolated in four households. Local emergency officials said the residents were safe and had sufficient supplies.