SafeAvon working to stop sewage pollution of the Warwickshire Avon

Tewkesbury Friends of the Earth (FOE) River Avon (sewage) Pollution

For some time, like a lot of people, Tewkesbury FOE have been concerned about the amount of untreated sewage Severn Trent plc is dumping into the River Avon, when they bypass treatment works. It has been identified that this is increasing year on year. We are hopeful that green groups along the river will join with us (currently talking to groups in Stratford, Evesham & Pershore) so we can establish testing over the longer period (providing a history of contamination from all sources).

At the same time we would like to collaborate in actions that the groups think could raise awareness of sewage dumping in their local area (supporting each other in these actions). We believe, while national groups dealing with pollution are working hard, they are being mostly ignored by the present government. Over the shorter term we would hope to apply political pressure locally and then use this to gain support from local political figures and bring pressure that helps bring about change at a national level.

There is a free app that we can use to collect the data, but we need help to collate, record and hopefully analyze the data over time, as well as building a web site and contact list of people interested in this project. While all help is welcome and needed, this is key to in the long / medium term.

 

Pollution

Natural Pollution; rivers are part of nature, and raw or untreated river water is not safe to drink. Rivers contain microbial life and pollutants from a range of natural sources; for example, defecation by wild animals and dead and decaying organisms in and around the river.

Farming; arable and livestock farming can contaminate rivers when manure, pesticides and fertilizers get washed of the land into the streams and rivers.

Urban and Transport; pollution caused by urban land use may be due to pollutants entering a watercourse via urban runoff, road drainage or atmospheric deposition.

 

Untreated and Treated Sewage pollution.

Untreated Sewage; During periods of heavy rain, Storm Overflows (SOs) from treatment works and Combined Sewer Overflows (CSOs) from the sewer network are used as a safety valve for the sewer system, preventing homes from flooding. Unfortunately, when these overflows kick in, rainwater mixed with raw sewage is discharged into our rivers. This means that the majority of what gets flushed down the toilet or poured down the sink – including non-biodegradable items like wet wipes – ends up polluting the river.

In theory, the rainwater should dilute the raw sewage and mesh screens should remove gross solids — however, the existing infrastructure can’t cope, leading to discharging into our waterways more and more often.

 

Treated Sewage; Domestic and industrial sewage has to be treated before it can be discharged to the environment. In built up areas, sewage is piped to the nearest water company sewage (wastewater) treatment works, where it is filtered and undergoes chemical and biological treatment to remove contaminants before releasing as treated ‘effluent’ back to rivers or the sea. Unless there is a designated bathing water or shellfish water nearby, there is no requirement to sterilize the effluent, so most sewage effluent discharges to rivers still contain high levels of bacteria and pathogens. Domestic properties and small businesses which are not connected to water company sewage networks will have their own local sewage treatment facilities, such as septic tanks or ‘package’ treatment works. The locations of all of these are not on the public register so we can’t map the risk, and the estimated half a million homes with non-mains drainage are likely to be a significant source of localised pollution, particularly in rural areas.

 

Misconnections; In the UK, it is estimated that there are between 150,000 and 500,000 houses with drain misconnections. Within a modern property, there are usually two sewers: a wastewater sewer and a surface water sewer. A wastewater sewer is where household water (e.g. from showers, sinks, toilets, etc.) is sent to be treated at a wastewater treatment plant, before being released into the environment. A surface water sewer is where rainwater and runoff go to be directly released into rivers or streams. Sometimes the two become misconnected, meaning that untreated wastewater is released into rivers, posing a serious threat to the environment and the health of river users.

 

Risks from Polluted Rivers

In 2021 there were over 370,000 discharges of untreated sewage into UK rivers, totaling over 2.7 million hours of pollution. The UK is consistently ranked as one of the worst countries in Europe for water quality, over three quarters of our rivers fail to meet required health standards and face multiple threats.

Water pollutants can cause disease or act as poisons. Bacteria and parasites in poorly treated sewage may enter drinking water supplies and cause digestive problems. Domestic and hospital sewage include a variety of dangerous germs and dumping it into the water without sufficient treatment can result in an outbreak of deadly diseases. Contaminated water are linked to transmission of diseases such as, diarrhea, dysentery, hepatitis A, typhoid, and polio. Absent, inadequate, or inappropriately managed water and sanitation services expose individuals to preventable health risks.

 

Pollution is putting an increasing pressure on the diverse wildlife that call our beautiful rivers home: from kingfishers to otters and brown trout. They can hurt digestion, damage body parts, and make it difficult for them to swim. They can also harm their ability to grow and reproduce. According to the Wildlife Trusts, rising pollution levels place 10% of freshwater and wetland species at risk of extinction. In Wales and England, 38% of fish health checks fail due to disease caused by pollution.

Outcomes

Our cherished way of life depends on clean water: healthy ecosystems provide wildlife habitats and places to fish, paddle, surf, and swim. Our economy depends on clean water: manufacturing, farming, tourism, recreation, energy production, and other economic sectors need clean water to function and flourish. With most river side towns having a high footfall for tourism, a smelly and weed choked river may not be the profile that it wants tourists to take home with them!

 

What are Storm Overflows

Storm overflows are part of an older type of sewer system (pre-1960s) when most properties were built with drains that carry together in one pipe, both surface water and foul water from homes and industry. This is called a combined sewer system. Storm overflows are designed to release excess storm water into rivers or the sea when this happens. There are about 15,000 storm overflows in England. Separate sewer systems have been built in the UK since the 1960s. The more modern system has one pipe for foul water, and a separate pipe for surface water. Despite separate sewer systems, property developers still have the right to connect surface water drainage pipes to the combined sewerage network. The biggest misuse of the sewerage network is sewer blockages caused by wet wipes and fat being flushed down the toilet or poured down the sink.