Raw sewage discharges into Langstone Harbour happen when stormwater comes in from the sewers faster than Budds Farm STW can treat it, and the buffer tanks fill up.
Recycling will not increase the works capacity, nor the size of the storm buffer tanks, it will not speed up basic treatment, so discharges will only increase with all the house-building and predicted more frequent severe storm events.
In fact, the benefit promised by Portsmouth Water for the harbours to reduce nitrates and algal blooms will be drastically reduced. Southern Water has not considered this in their Habitats Regulation Assessment.
If you want to know more read on …….
The water recycling treatment process takes final effluent water from the end of the Budds Farm Sewage Treatment works process, this is water that would currently be discharged through the long sea outfall in to the Solent. It therefore does nothing at all to increase the capacity of the works. When the sewage works reaches its existing capacity the storm tanks will still overflow into the harbour via the short sea outfall, as they do now. It will make no difference at all to the regular occurrence of storm overflow events of raw sewage in to Langstone Harbour.
Surely it would be better if Southern Water instead invested millions of pounds of customers money in providing a more robust solution that treats more sewage, providing more capacity at Budds Farm STW, rather than spend millions on taking this waste product and treating it to put in our drinking water.
Worse still, because the recycled effluent will be pumped up to the Havant Thicket Reservoir every day of the year, to keep the reservoir topped up, less spring water will need to be pumped up to the reservoir.
This creates 2 issues;
- There will be less spring water mixed with the recycled effluent in the reservoir.
- A key environmental benefit that was promised at the time of the reservoir planning application to reduce nitrates going into the harbour will be lost, or drastically reduced. The spring water which currently overflows into the harbours contains elevated levels of nitrates, the more spring water that is pumped up to the reservoir, the less nitrate that will go into the harbours. This would have helped to reduce the risk of algal blooms which form mats on the mud flats causing adverse impacts to biodiversity. Disappointingly, this adverse in-combination impact has not even been considered by Southern Water in their Habitats Regulation Assessment.