Dairy organisations are teaming up to find out how much farmers have spent on environmental initiatives on their properties in the past five years.
Federated Farmers and DairyNZ are collecting the information region by region to gain a national overview, following a survey in the Manawatu-Wanganui region last year.
That survey found more than 160 farmers, out of 900 interviewed, spent a total of $18.5 million on environmental improvements, including effluent systems, stock exclusion from waterways and riparian planting.
Federated Farmers dairy chairperson Andrew Hoggard said it had been difficult to quantify all the investment that farmers have made across the country.
"At the moment, we're only able to provide anecdotal evidence and it would be good to provide more factual evidence.
"We don't really have a lot of information around the amount of money farmers are investing in this space, we do know farmers are doing more and more but we can't put a quantifiable number on it.
"We have had it out there for about a month now - the request to farmers for information - we have had some in but we'd like a lot more."
Mr Hoggard said the survey was expected to be up on the DairyNZ and Federated Farmers websites for another month.