At least 3.4 billion litres of water will be saved every year under new water targets Fonterra launched this month, the co-op says.
Fonterra has dropped its forecast payout from $6 to $5.30/kgMS; it also announced an estimated dividend range of 25-35 cents per share.
Brown says even though farmers are aware of the prevailing market conditions and the effect they have on the price they receive for their milk the announcement will add to the challenges being faced on-farm.
"It is in these seasons that farmers will want to receive the full benefit from the integrated supply chain that their co-op provides.
"As farmers we are all too aware of the volatility that underpins our industry and this announcement will put real pressure on some farmers' cash flows.
"It is important for farmers to remember that while this is a forecast it is vital that you continue to exercise real prudence in your financial planning."