Founding NDDT trustee Kim Robinson said the trust knew the work was "immensely valuable to the industry, so it's nice to get that validated independently".
The Nimmo-Bell study assessed benefits from the six NARF projects over the past 20-30 years, she said.
NDDT is a joint initiative between Fonterra and NARF formed in 2006 to support Northland farmers in securing funding for quality dairy research.
The research farm has an 84 effective hectare milking platform which is of predominantly flat contour.
Currently the farm is milking 260 cows with an average production over the past three years of 1150 kgMS/ha.
There is a modern 30-a-side herringbone shed with Protrack and feedpad with the capacity for three working vats for farmlet trials.
The farm has the unique ability to run systems trials on up to three farmlets with up to 80 cows each. This gives enough scale for robust comparisons.
"One of our key drivers is that the research projects we take on are all farmer driven. They are in response to real on-farm challenges that farmers face," Ms Robinson said.
Nimmo Bell's Brian Bell said the purpose of his firm's study was to show Northland farmers the value the research programme had added to their incomes using specific examples.
"Farmers will see that value through the increase in profitability to their farms compared to what it would have been if the research hadn't been done," he said.
The benefits were only assessed north of Auckland, but the impact of the split calving and kikuyu work in particular, further south, had also been significant and was not included in these figures.
"There are definitely wider benefits to farmers nationwide. Certainly, with the steady march of kikuyu south. managing that is going to be an increasing task for farmers," Mr Bell said.
Ms Robinson said the four largest projects undertaken on the research farm - split calving, endophytes, kikuyu management, and farming without inputs in variable climates, had all addressed issues that had originated in Northland, "but are spreading down the country as climate change occurs".