New Housebuilding in the UK Held Back by Pollution from Factory Farms

Just had a look and apparently the problem is that housing developments add to the problem with extra wastewater and sewage from new homes as well as run-off from construction sites.

I know and I'm aware of the massive damage that it does to our waters, I'm just not sure why it's used as an excuse to not build houses in such areas. Does housing add to the problem of nitrates getting into the water or something? So many problems would go away if went organic and banned all fossil fuel derivatives.