"Locals at Solai shopping centre talk of a huge explosion" before seeing a cloud of water move their way.
Nakuru County Governor Lee Kinyanjui stated that his office will do its best to ensure those affected are taken to a safer place.
A local television station said 20 bodies had been recovered so far.
The 9pm horror rendered over 300 families homeless and about 2,500 residents were affected. He, however, said the extent of the damage was yet to be established.
KRC has already made an appeal for $5 million following the heavy rains that have wreaked havoc across the country with 11 counties been most hit by the latest spate of floods.
Police officers speaking from the scene say the private Patel dam, used for irrigation and fish farming, may have lacked a proper outlet.
This image shows a child being rescued after a dam failed near the town of Solai, Kenya, on May 9, 2018.
A search-and-rescue operation is under way as several people are feared to be trapped in thick mud which spewed from the reservoir, spreading over a radius of nearly two kilometres.
The Patel dam belongs to a farmer who also has two other reservoirs on their land. So far over 300 homes are confirmed to have been affected.
The government said on Wednesday that the rain had killed 132 people and displaced 222,456 others in 32 counties since March.
Kenyan authorities and humanitarian organizations airlifted stranded residents to safety and provided aid to isolated communities after weeks of heavy rain and landslides.
A desk has been set up to make reports on missing family members.