by Nic T Brown
A while back the Conservation Society and my neighbours in Riverside Walk asked me to investigate sewage pollution in Tamerton Foliot. Here is an update:
Combined Sewer Overflows
Pollution is now topical and I guess most have heard of Combined Sewer Overflows (CSOs) whereby Southwest Water (SWW) are licensed by the Environment Agency (EA) to release sewage into the water courses. Although not exactly desirable, these work ok normally as they come into play in times of high rainfall, so the sewage is diluted.
The stream through Tamerton Foliot that leads into Tamerton Lake and onto the Tamar collects water from quite an area – basically our side of the ridge lines formed by Tavistock Road, and Budshead Road towards Ernesettle, then from the North it’s this side of the top of the village. Any pollution incident then in Belliver, Roborough, Southway, ends up in Tamerton Foliot!
There is an infamous CSO below Belliver Estate (the pin marks the manhole, and the arrow shows the discharge point into the stream) – you can find this by walking upstream along Coombe Lane then beyond.
In August 2016, the weather was dry and a pollution incident caused by the build-up of commercial-use wet wipes created a blockage in the sewerage pipe in Widewell Woods. This led to untreated sewage being released into the Tamerton Stream
This Category 1 (major) pollution incident had a substantial impact on the stream, unfortunately killing more than 80 Brown Trout.
This incident resulted in an Enforcement Undertaking between the Environment Agency with South West Water (SWW) to the value of £350,000.
This money enabled Westcountry Rivers Trust to conduct work to improve the urban watercourses in the Tamerton stream catchment. This has led to the creation of WRT’s Plymouth River Keepers (PRK) project. I am the community’s rep on PRK and our work is on their website.
The Environment Agency has recently released a map showing where Combined Sewer Overflows (CSO) have released sewage into water courses during 2022. Plymouth Live published it here https://www.plymouthherald.co.uk/news/plymouth-news/every-plymouth-sewage-hotspot-near-8552351
From this, we can see that a CSO behind Cheshire Drive in 2022 had 13 spills and released sewage into the stream for an equivalent of 6 days. Tamerton Foliot Sewage Pumping Station on Station Road is also a CSO which had 32 spills releasing sewage for 71 hours.
Tamerton Foliot Sewerage System
Like the water system, so to the sewage flows downhill and Tamerton Foliot ‘hosts’ a major sewer taking all the sewage from Belliver, Roborough, Southway etc. It ends up in a huge pipe encased in concrete that goes under the gardens South of Riverside Walk, across the fields and onto Ernesettle Sewage Works. Most Tamerton Foliot sewage goes to the pumping station along Station Road, then deep under the stream to join the main sewer. I have obtained a full set of maps which are on the Tamerton Foliot Conservation Society Website. An extract is here:
The current day problem – Overflowing manhole covers
From the map above, you will see a major sewer coming down Coombe Valley crossing Church Row Lane and joining up with the main sewer from Southway etc. In times of high rainfall, the manhole in Church Row Lane blows and raw sewage flows down the road into the stream carrying with it waste, paper, sanitary products etc. Another manhole regularly blows below Cann Cottages and raw sewage flows down the fields into the stream.
I have been trying to bottom this out with the EA and SWW. I once had good contacts with managers of both organizations, but they have moved on. Both organizations are now impenetrable to me! I phone up the call centre and are told they work in ‘Functional Teams’ and someone will call me back… they never do!
What we can all do please, is to report an overflow as its happening and take photos. Eventually this might trigger the EA to take action against SWW to sort things. We do benefit by a community member who lives at the top of Church Row Lane who keeps an eye on the manhole there. Please can the general community help also?
The Environment Agency are the responsible body for recording and responding to pollution incidents in England – they have a dedicated incident hotline that you can call 24 hours a day, 7 days a week 0800 80 70 60 you can also report incident via email to email@example.com
Before my contact with SWW disappeared, he reported to me the new demand on the system is thought to caused by the new Mayflower Treatment Works. There is outfall from the works, and this comes down the hill in a pipe next to the fresh water supply to the new major pumping station along
Coombe Lane. Here, the outfall enters the sewage system – so just before Tamerton Foliot. SWW told me they were trying to balance the system to relive the situation… clearly this has failed so far. However, SWW did put in a stronger manhole in Church Row Lane. The cover does not blow now,
the sewage just fountains up the cracks … before flowing down into the stream!
If anyone reading this is with the EA or SWW and can help put me in touch with managers responsible for our area please can they help?