Treat Southern Water’s Beachbuoy with caution.

Southern Water’s Beachbuoy real time mapping of combined sewage outfall (CSO) spills is a great addition to the information to residents using the seas around the shores of the Solent. It gives warning of possible pollution close to the outfalls, all of which are identified on the system. It shows when a spill starts and ends and flags up any spill in the last 72 hours as well as giving historic data. We’ve described it in a little more detail here.

However, be aware that Beachbuoy may give false readings.

In late October and early November after some rain over the weekend Beachbuoy showed a spill from Marsh Road at Gurnard on the Isle of Wight starting on the Sunday morning.

By Wednesday Solent Protection Society (SPS) picked up that it was still spilling after some 3 days and had not been reviewed, whereas most other spills from the weekend had been reviewed and were short lived.

Marsh Road is a sewage pumping station and so our initial thought was that perhaps the pumps had failed. Further investigation of Beachbuoy showed that the spill was actually coming from a CSO about a mile or so inland on the Luck stream which is below Northwood Village, but the cause could still be a problem at the pumping station. The stream flows into Gurnard Bay where there is regular sea swimming and dinghy sailing throughout the year.

By Thursday it was still showing spilling and so we decided to contact Southern Water. There is no obvious contact point for reporting such spills except the general helpline so that is what we called. The operator was not aware of Beachbuoy and did not have a system that enabled her to pinpoint the pumping station, however she was good, took the problem on board with details and confirmed she would contact the technical team. Southern Water’s new public relations culture is clearly working.

In the afternoon we received a call from a SW technician (another plus to SW) to say there was no problem with the pumping station could we give more details. We arranged to actually meet on site at the CSO and the result was that the sensor needed a manual reset. It was clearly not a priority at the time and so continued to register a spill even though it was not actually doing so. It took another 2 or 3 days before it was reviewed centrally and the actual spill time reduced from over 6 days to a few hours.

So be wary that until a spill is reviewed it may be giving a false reading on duration, although a spill is most likely to have caused it to trigger in the first place.

It would be helpful if Southern Water made it easier to report such spill queries in the future and reviewed data as soon as possible to avoid false information.