A $250,000 grant has doubled the amount raised for a $2.4 million hydrotherapy pool, aimed at Hamilton's disabled, ill and injured.

The grant made by the Perry Foundation, takes the total raised by the Hamilton Hydrotherapy Pool Charitable Trust to past $500,000.

Trust chairman, David Peart said it was the biggest donation received since the group began fundraising for the hydrotherapy pool a year ago.

A public hydrotherapy pool, in which the water is heated to between 33 and 35°C, would be used by physically and mentally disabled people, the elderly, pregnant women, sports injured patients, physiotherapists and their clients and more.

With a promise of $130,000 from Trust Waikato, Mr Peart said the grant put the charitable trust in a good position to apply for lotteries funding and to get the project brought forward.

"Our next objective will be to go to the (Hamilton) City Council in the annual planning this year and say 'look we now have well over $500,000 towards this project and we anticipate raising considerably more and we want you to bring it forward.

In 2006 the council agreed to fund $180,000 toward the pool's design at Te Rapa Wateworld and to contribute 33 per cent, around $590,000, toward the cost of construction.

However Mr Peart said the current plan to build the pool in the 2011-12 financial year was too far away. "We'd like to see construction begin next year. It will take at least two years to build so we'd love to see it completed in time for the 2009-10 summer.

He said a public hydrotherapy pool was desperately needed in Hamilton.

Fundraising for the pool began in the 1980s but the $75,000 raised by Hamilton East Rotary Club was "lost".

Rotary says it gave the money to the city council but the council has not record of it.