Berkeley Homes, Site Sewage Problem
We would like to thank members of the committee that have contributed towards this study into the sewage issue in Cranleigh.
This information has been passed to the Inspector of the Berkeley Homes Appeal, Waverley Borough Council, the Environment Agency, Thames Water, Cranleigh Parish Council and the Neighbourhood Plan Group.
Cranleigh Sewage Works opened nearly 50 years ago to serve between 10,000 and 15,000 people in Cranleigh, Ewhurst, Hascombe and other local villages. Addition of the recently approved Amlets Lane and Crest Nicholson sites will take it over the 15,000 residents limit when they are built.
The river Cranleigh Sewage Works discharges its effluent into what is called “Cranleigh Waters”, and the quality and quantity of effluent is controlled by the Environment Agency (EA) via a document called a “Permit Limit”. The last Permit Limit was issued in 2009, and it is now long overdue for renewal. If Thames Water exceed the permitted level of effluent that is discharged into the river they can be fined.
Recently, Cranleigh Waters has been re-classified by the EA as “ephemeral”, which means it flows well in winter but not in summer.
This issue with the flow rate started around 4 years ago and it has got progressively worse. On 6th October 2015, it stopped flowing altogether for a period.
This is due they say to water abstraction and low aquifers ( a body of permeable rock which can contain or transmit groundwater) upstream, increasing population density and onset global warming.
The consequence of this has been to turn Cranleigh Waters into a “eutrophic” water body, which means that it is rich in nutrients and promotes plant growth, at the expense of providing a suitable habitat for fish, amphibians and invertebrates.
Since 2009, The EA has classified Cranleigh Waters as “Eutrophic and Bad”, the worst category on their ratings scale.
Under The Environmental Permitting (England and Wales) Regulations 2010, the 2009 Permit Level should have been regularly reassessed by the EA and reissued, but that has not happened.
Recent data issued by the EA on the 7th December 2015 shows that the Permit Level is now being exceeded in all three key water body pollution indicator categories, Solids, Biochemical Oxygen Demand and Ammoniacal Nitrogen.
Before considering whether the Berkeley Homes site should be developed, a new Permit Level should be issued by the EA and a study made to assess whether the Cranleigh Sewage Works can be extended to cope with increased demand, and to assess if Cranleigh Waters can take any more pollution. Cranleigh has recently been designated a “Protected Zone” by the EA to help defend a major drinking water abstraction point for Guildford, a short distance away downstream.
Waverley Borough Council have told us that they have not assessed the sewage position in Cranleigh, despite the significant number of planning applications, but are now looking into it, having had the matter brought to their attention by the Cranleigh Society.