The chief executive of Norfolk Wildlife Trust, Eliot Lyne, said his organisation needed more time to review the proposals.
But he said it was worried about wider changes to planning rules and how they affected natural habitats.
“We are concerned that it weakens existing protections for Norfolk’s nationally and globally important wildlife sites such as chalk streams, wetlands and valley fens,” he added.
Mark Dye, a chalk stream campaigner for the Gaywood River Revival group in west Norfolk, said: “Fundamentally, if you are polluting a chalk stream or a river and you’re putting more and more pollution into that river, and not seeking to address the underlying causes of that, then it’s only going to get worse.”
Steve Turner, executive director of the Home Builders Federation, claimed pollution from farmers was a bigger issue than new homes and he criticised water companies for not investing in infrastructure to stop sewage entering rivers.
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