Washington, Sep 2 (IANS): Houston's recovery from Hurricane Harvey flooding in the US will be a "multi-year project", Texas Governor Greg Abbott has said.

"This is going to be a massive, massive clean-up process," he told the ABC News programme Good Morning America, BBC reported on Friday.

US President Donald Trump is to propose an initial $5.9 billion for recovery efforts, but the Texas authorities say the state might need more than $125 billion.

More than 40 people have died in the storm and its aftermath.

Recovery efforts in Houston are under way as the water recedes but search-and-rescue teams continued their work in the nearby city of Beaumont, Abbott said on Friday.

Officials in Beaumont, a city of about 120,000 people near the Louisiana border, said Harvey's flooding has cut off their drinking water supply.

Brad Penisson, a captain with the Beaumont fire and rescue department, said on Friday the city was setting up water distribution stations to ensure residents had clean drinking water.

Harvey made initial landfall as a Category 4 Hurricane in Texas last Friday, and has since dumped an estimated 20 trillion gallons of rain on the Houston area. It was later downgraded to a tropical storm but continued to batter Texas with rain.

An estimated 93,942 homes in Texas have been damaged or destroyed in the wake of Harvey, according to the Texas Division of Emergency Management. About 80% of Texans do not have flood insurance to cover the wreckage.

The storm has displaced thousands and about 32,000 people remain in shelters across the state, Mr Abbott said.

Visiting Texas, Vice-President Mike Pence on Thursday promised federal help to "rebuild bigger and better than ever before".

Pence paid tribute to the people of Texas: "The resilience of the people of Texas has been inspiring."

The White House also said President Donald Trump would donate $1 million of his own money to the relief effort.

Dell Technologies CEO Michael Dell and his wife, Susan, have also pledged to donate $36 million to launch a Rebuild Texas Fund with the aim of raising more than $100 million for recovery efforts.

The couple, both Texas natives, said on Friday they plan to donate $18 million immediately to launch the fund through their eponymous foundation.

Firefighters in Houston have been carrying out door-to-door searches for survivors and bodies in an operation that could take up to two weeks.

Hundreds of thousands of residents who were evacuated or chose to leave are being warned not to return home until they are told it is safe to do so.