NFU Cymru has voiced "frustration" over the Welsh government’s failure to deliver "urgent changes" to agricultural pollution regulations.
The comments follow the publication of the statutory four-yearly review of the controversial regulations, which have been rolled out gradually since 2021.
Led by Dr Sussanah Bolton, the new independent review examined the effectiveness of the measures designed to reduce water pollution from agricultural sources.
It found that while the current regulatory approach was "sound", there were "significant opportunities to make improvements to benefit the environment and farmers".
These include improved targeting, reducing burdens on low-risk farming activities, increasing clarity for farmers and addressing regulatory gaps.
Following the review, the Welsh government issued a written statement by the Deputy First Minister and Cabinet Secretary for Rural Affairs, Huw Irranca-Davies.
"Water quality in Wales is still being detrimentally impacted and improvements must continue to be made," Mr Irranca-Davies said.
"Whilst the causes of pollution are not limited to any one sector, agriculture remains one of the main contributors."
NFU Cymru called the Welsh government's response to the review "very frustrating" as it failed to "reflect the sheer desperation of farmers in Wales".
The union has had long-running concerns about the Control of Agricultural Pollution Regulations, accusing them of being costly, inefficient and bureaucratic.
NFU Cymru Water Quality Group Chairman, Martin Griffiths said: "Farming families are facing staggering costs and an unworkable regulatory burden that is challenging farm business viability.
“NFU Cymru would welcome better targeting of the regulations and reducing burdens on low-risk farming."
The review makes recommendations in key areas such as better targeting regulations at polluting activities while reducing burdens on low-risk farming.
It also explores alternative measures, particularly regarding closed periods and the 170kg nitrogen per hectare manure limit.
But Mr Griffiths said the review suggested that farmers could wait up to three years to see changes happen. "Farmers cannot wait another three years," he said.
He went on to say: “Farmers will have little confidence in recommendations to only consider the possibility and explore alternative measures for closed periods and the 170kg nitrogen per hectare limit.
"The reality is that this work has already been undertaken and submitted to Welsh government in line with the legislative requirements two-and-a-half years ago."
NFU Cymru said it would consider the report in more detail, reviewing the recommendations against NFU Cymru’s evidence submission last December.
Dr Susannah Bolton, who led the review, said: “The engagement I have conducted for this review has demonstrated that there are strongly shared aspirations for improving water quality in Wales.
"I am genuinely optimistic that the recommended changes to the regulation will enable a greater degree of common agency and shared responsibility to address the challenges.”
