Architect Michael Payne says a move to divert stormwater from a nearby new development to the quaker settlement in Virginia Rd may be a first.
"There was no record of a land-owner willingly taking storm-water from another," said Mr Payne.
The water will be pumped across the the hospice section that sits between the two properties into a new dam at the rear of the quaker settlement property.
Mr Payne gave a tour of the property to show the dam and the 10kw grid-connected solar panel at the settlement as part of the permaculture weekend events.
"We had four lawyers and a team of engineers as well as the council involved with the dam project. We had to give reassurance that the dam would hold the water."
The solar panel system installed two and a half years ago is harvesting an average of 35.83 kilowatt/hours per day.
Mr Payne says while the monetary return on the system has been severely cut by Meridian reducing what it pays for units fed into the grid by more than 50 per cent, "the actual production is satisfactory and we have effectively offset the equivalent of five tonnes of CO2".
"Meridian pay us 25 cents per unit for the first eight units but only 10 cents per unit after that, and in summer we can produce eight units before breakfast.
The 20-acre Virginia Rd site is owned by a Quaker trust. There is no individual ownership of land: tenure is "guardianship".
In Maori terms it can be seen as a "papa kainga", communal facilities kept warm by people living in the encircling houses.