Ontario food banks say they're seeing an increase in clients unable to afford the rising cost of hydro bills.

The Ontario Association of Food Banks says high electricity bills are having a "devastating impact" on the lives of low-income Ontarians.

Food banks serve 335-thousand adults and children each month, and the association is calling on the Liberal government to boost hydro assistance, particularly for the most impoverished families.

In a report released Monday, the association says many food banks have stepped in to offer their own utility assistance and hydro payment plans to clients.

But it says that even the food banks -- like many Ontario businesses -- are struggling with their own hydro bills.

Higher hydro bills mean less money to spend on critical supplies at the Orillia Lighthouse Shelter.

"Now we're spending the money on hydro instead of say putting food on the table for the clients in our soup kitchen or hygiene and stuff in our shelters like toothbrushes, tooth paste, soap, shampoo," says Sarah Ulrick, client services coordinator.

The Lighthouse is a 24-hour service like the Salvation Army, which means no downtime to shut off the power.

"Our cost keeps escalating as far as electricity and hydro are concerned. It does impact first of all our own operation, and then it impacts the clients because we are unable to have that extra resource in order to get them to the next level of their needs,” says Maj. Doug Lewis of the Salvation Army.

Another challenge is that high costs could also slow down donations.

"People are going to make that determination do I give that 100 donation to the foodbank or do I pay my hydro bill,” says Peter Sunborg, executive director of the Barrie Food Bank. “Hopefully we don't get to that stage."

Premier Kathleen Wynne said in a recent speech that more relief is on the way, in addition to an eight per cent rebate set to kick in on January 1st.

With files from The Canadian Press.