Mr Grafas said money raised would go through Samaritan's Purse, the biggest freshwater supplier into Cambodia, which would set up the wells throughout the country.
He said that said if somebody asked him how much of their money actually went towards the charity, "the answer would be all of it. The idea behind the 100 per cent and the tracking is to redeem how people view charities. We want them to see we have actually set out what we said we would do."
Mr Grafas said the organisation had been working in Kampong Chnang but had finished building wells there and would move northeast in the country to Kratie.
"The people we were working with in Kampong Chnang have told us it's a whole other level of poverty there [in Kratie]."
Excelso Coffee Roasters' Carrie Evans said she had been trying to work out a way to get involved in more sustainable projects when Mr Grafas pitched the idea.
Mrs Evans said they had already sold enough good.coffee to give 43 people freshwater for life and did not have a cap on how many people they wanted to help. "For us, we want to be able to say look, this is our well in this village and Excelso has done this. That's our goal in our workplace and people want to do good things, but often want to have something physical which has done the good. If you have a gift that you can see and use, but know that you are doing a good thing at the same time, it makes a big difference."
Samaritan's Purse would start "making holes in the ground" from about March and coffee buyers would be able to receive co-ordinates for the well they help build.