Manjhi in his letter dated November 6 and released to the press, said 73 per cent of Bihar's land mass, particularly a vast swathe in north, faced flood fury every year though all rivers flowing through the region, barring Budhi Gandak, originate in Nepal and Tibet Autonomous Region of China.
The total flood-affected area in Bihar was 68.8 lakh hectares and comprised 17.2 per cent of the total flood-prone area in the country, he said.
"Our miseries don't end with floods ravaging vast swathes of land in north Bihar as south Bihar reels under drought situation every year due to inadequate rainfall and lack of water resources," his letter said.
The Chief Minister said the state government has been unable to take remedial measures to contain flood problem in north Bihar due to discharge of water from Nepal and upstream in the Himalayan region as the issue was international and urged Modi to take up with that country projects to prevent discharge of excess water to north Bihar.
The projects mentioned were construction of Saptkoshi high dam multi purpose project, Sunkoshi storage-cum-diversion project, besides construction of dams at Nunthore and Chisapani on Bagmati and Kamla rivers.
Manjhi has also pleaded for removing obstacles in constructing of dam at Massan on Budhi Gandak river to control flow of river water into upstream areas. In addition, he urged the Prime Minister to direct the release of the Centre's share of funds for construction of irrigation and water management schemes in Bihar under the Flood Management Programme and related schemes.
With siltation being a major problem, Manjhi requested for framing of a national silt management policy so that huge quantity of it lying in all rivers in Bihar is removed and managed properly to ensure uninterrupted flow of water in their upstream courses.