Tracy Lovejoy, a planning lawyer with Lanyon Bowdler, said the so-called 'Dutch case' is causing major headaches for developers because councils are refusing to give permission for new developments which have any impact on certain rivers.
She said the issues related to applications which had the potential to impact designated Special Areas of Conservation, principally certain protected rivers.
Tracy said: “Wildlife regulator Natural England is the official government adviser on the protection of natural habitats, and many councils rely on its guidance, which used to be that development could go ahead as long as reasonable conditions were met.
“For instance, in south Shropshire, the River Clun and its tributaries are subject to a nutrient management plan, and the stance of Natural England was, until recently, to allow development even if it would increase nutrient levels, as long as it could be managed by the mitigation measures in place.
“However, since the Dutch case, planning authorities can no longer take conservation measures into account, unless the outcome of those measures is certain.
“That has meant that Natural England now only recommends approval of planning applications where there would be no impact on Special Areas of Conservation.
“This has led to a nervousness amongst authorities and we have heard reports of a virtual freeze on approving certain types of development, with the inevitable result that the construction of houses across the country is being held back.”
Lanyon Bowdler recently dealt with two cases in Shropshire and Herefordshire which were affected by the issue.
“The first case related to a modest residential development, where the developer had to spend a lot of time coming up with a strategy of how to dispose of the foul sewerage from land - even though it was using the same licensed site as every other home in the area," Tracy said.
“In the other case, the issue revolved around scientific doubt. The applicant’s hydrologist advised that the proposed development of pheasant rearing would produce fewer nutrients than the site’s lawful use of agriculture.
“However, her views were rejected without equivalent scientific evidence to counteract them. Naturally, she was surprised that her professional expertise could be apparently disregarded in the appeal process and she is currently pursuing the matter with Natural England.”
She said while the management of water courses is clearly an important issue, there is hesitance to approve certain developments despite specific evidence.