New details have emerged on what caused the deadly flooding in Mai Mahiu on Monday dawn.

Officials said a blocked railway drainage accumulated water before its wall burst.

Heavy rains had been experienced on Sunday in the area and upper sides of Kinale.

“In the current unusual rains, the ‘Dark Tunnel’ – the railway line drainage at Old Kijabe- blocked leading to disastrous accumulation of water that broke the wall causing floods earlier today (Monday).”

“This has caused loss of lives and adversely affected Old Kijabe and Mai Mahiu and its environs,” said Chege Macharia, the executive director of Kijabe Hospital.

The hospital is near the place where the drainage had blocked and accumulated water.

Water Resources Management Authority (Warma) also said the water came from a water-filled gulley in Kiambu County that flowed down to Naivasha Sub-County and not from a dam.

The waters originated from a gulley near a railway line that was blocked, thus forming a temporary water catchment over time.

With the onset of the heavy rains, the gulley burst, leading to water collected flowing to lower-lying areas and leaving behind a trail of death and destruction.

The revelations addressed earlier concerns about the source of the water that swept almost 100 homes killing 50 people. Dozens are missing after the incident in Kianduma village.

More than 100 are admitted to hospitals. The search and rescue mission is ongoing in the area amid heavy rains.

Deputy President Rigathi Gachagua led government officials to the scene to condole those affected.

“The damage is deep and devastating. It has also triggered a massive humanitarian crisis akin to what has been witnessed in other parts of our Nation as the enhanced rains leave trails of death, destruction and displacements. Nature’s fury is immeasurable,” he said.

Transport Cabinet Secretary Kipchumba Murkomen dispatched National Youth Service (NYS) personnel to the site of the Maai Mahiu tragedy to help in the search and rescue mission.

The mission entered its second day Tuesday as the Cabinet met to discuss the matter and others that have been reported in the country.

Murkomen also revealed that 300 people have died so far due to flooding after the long rains began in the country.

Motorists plying the Mai Mahiu-Suswa/Narok highway were Monday night advised to seek alternative routes after debris was swept into the roads following Sunday night’s heavy downpour.

The Kenya National Highways Authority (KeNHA) issued an alert, saying motorists should brace for heavy traffic along the said roads as they are impassable at the moment.

KeNHA said the heavy rains in the catchment areas of Kinale and Kijabe led water courses to experience an upsurge which then led to the washing away of debris and several houses.

“The Kenya National Highways Authority would like to notify the public of the closure of Mai Mahiu – Narok Road,” said a statement on Monday evening.

“This follows sudden siltation, coupled with heavy debris deposited on a section stretching over a kilometre this evening at Suswa area, about 27 kilometres from Mai Mahiu town towards Narok.” s

The authority said the closure will allow smooth clearance of the siltation and avoid incidents of vehicles getting stuck, among other possible dangers.

“The Authority advises motorists plying this route to use alternative routes including the main Nairobi – Nakuru Highway.”

The route is key in connecting many from South Nyanza to Nairobi.