The letter goes on to ask for central government intervention to resolve the high level of phosphates in the river and the ramifications this is having on house building in the region.
It also asks for help with its increasing issues with flooding, which it says are caused by landowners and farmers not paying enough heed to flood management.
In the letter, councillor David Hitchiner describes the problem with the river Wye beginning in 2020 when an algal bloom “wiped out miles of river ecology”.
He says that three of the causes of the bloom are temperature, low flow, and sunlight, which are outside of the council’s control, but the fourth cause - nutrients - is within it.
“We can, should and must ensure that the excessive nutrients that are killing the river are radically reduced”, he writes.
Hitchiner adds that “although Natural England and environment agencies are equally responsible for the protection of the river Wye’s Special Area of Conservation habitat and water quality respectively in England, it is with great disappointment that neither of these agencies have been forthcoming with a solution”.
The letter lays out the actions the council has “felt compelled” to take in order to be able to build houses in the area.
These include purchasing land for the construction of wetlands to remove phosphate from small Welsh Water sewage works, buying high phosphate yielding land for re-wilding, and commissioning an interim delivery plan to set out, among other measures, a phosphate calculator.
Nonetheless, Hitchiner describes these actions as a “sticking plaster” which do not address the core issue.
The letter says that pollution from agriculture, in particular intensive poultry units in Wales where the river Wye begins, is the leading cause of the high phosphate levels.
The high levels of nutrients in the river have led to the council being unable to approve the building of new homes since October 2019, due to new guidance brought in by Natural England.
In November 2018, the European Court of Justice issued a judgment that was to have major implications for the development industry and local authorities. The so-called Dutch Case in effect set new, higher environmental standards for developers to protect sensitive habitats.
In response, Natural England issued new guidance to certain councils including Herefordshire taking a much tougher stance on pollutants such as nitrates and phosphates entering water environments. In the Solent - an area frequently cited in Hitchiner’s letter as having received money from central government to help with the issue - the regulator was concerned that sewage, generated as a result of new development, would harm the integrity of EU protected areas therein.
Nitrate enrichment can lead to eutrophication, whereby nitrate and phosphorus overloading encourages algae blooms that can starve a body of water of oxygen and kill aquatic species.
As a result, many councils stopped issuing planning permissions for thousands of new homes until a solution allowing schemes to show 'nitrate neutrality' could be found.
A DEFRA spokesperson said: “Making sure we have clean rivers is an absolute priority and we are working urgently to reduce the environmental impacts of all sources of pollution – including those from agricultural practices and storm overflows.
Natural Resources Wales has been approached for comment.