The remaining 50 per cent of funding would be provided by the trust from pool revenue
It already had ideas of how to increase use of the facility.
In the meantime the trust would investigate whether plans to spend $2.9 million on upgrading the pool to make it last for a further 10 to 15 years were practical.
The $2.9 million quote to upgrade the pool is higher than council's $1.4 million because it includes a warranty on an Italian-manufactured lining.
The trust would also investigate spending a further $1.9 million on developing areas such as a cafe and gym to boost revenue.
Mr Perry said it had already spoken to a swimming club keen to move into the facility.
"Clearly it is past its use-by date in many respects," he said. "Essentially the key is to restore what we have got."
School children and health experts put forward passionate arguments at yesterday's draft long term plan hearing on keeping the pool open, saying there was already a severe shortage of pool lanes in the city.
Hamilton West School and St Columba's School students said they could use the pool without having to share it with other groups and it had great spectator seating. It also saved Hamilton West School money on buses.
St Columba's physical education teacher Grant Stuart said the school was struggling to run its swim programme since its own pool closed in 2005 and closing the municipal pool would make it even harder.
Sink or Swim lobby group spokeswoman Katherine Luketina said the council should change the city's name from Hamilton to Hamil-drown if it shut the pool.
Sink or Swim suggested alternative and cheaper options to keep the pool afloat including keeping it as a concrete pool and using an alternative heating system.
City councillors questioned why the city council was being forced to pick up the bill for pools for school use because the Ministry of Education thought they were too expensive to run.