A quick search of the BBC news web site for ‘sewage discharge’ brings up about 100 quite recent articles on the subject such as this one about the Thames. This one puts the problem in the European context.
The problem eventually ends up in the sea and SURFERS AGAINST SEWAGE have campaigned on this issue for a long time and their website is fairly graphic. To quote from their web site :
One of the biggest pollution problems along the UK coastline is still sewage. Despite SAS’s huge success at virtually eliminating all continuous sewage outfalls around the UK there are some notable ‘brown spots’ across the country where raw sewage is still discharged on a daily basis, including Brighton, Guernsey, the Thames and across Northern Ireland. The major nationwide threat nowadays however is combined sewera municipal drain or a drain serving more than one property overflows (CSOCombined Sewer Overflow. The discharging, during storm events, of untreated waste water from a combined sewer into streams and rivers’s) and their misuse by water companies.
According to the water industry itself, there are approximately 31,000 CSO’s around the UK, many of which are completely unregulated. The CSO is a kind of emergency outlet for the sewerage system, discharging raw sewage and wastewater into rivers and the sea when the system is overloaded. However, it appears that many CSO’s are being used too frequently as a means of regular sewage disposal, not just in the extreme weather conditions they are designed for.
The problem exists for several reasons:
- some of the systems are still old or inadequate for increasing population densities.
- In some cases, discharges are deliberately allowed to happen. For instance many streams and rivers are licensed to receive overflow from drains a certain number of times per year, often during periods of high rainfall when surface water runoff overwhelms the drainage system. This known as a CSO. This is often abused
- In other cases the problem is chemicals which do not break down properly in the sewage works. Typical of this problem are hormones in the sewage, such as those produced by the female contraceptive pill. They damage fish populations by feminising the male fish as in this article.
- sometimes it is by accident like when 100 million litres of sewage leaked into the Firth of Forth in 2008
There is an Environment Agency map called Bathing Water Quality which shows the water quality for English beaches.
There is growing concern about the huge amount of microfibers which are being released into rivers and the sea. These are produced when clothes are washed in washing machines and the worry is not so much about the fibers themselves as about how they can bioaccumulate toxins as explained in this Guardian article
Handling waste water and sewage locally on site by means of composting toilets and grey waterThis is the waste water that comes from the baths, basins, showers and washing machines. Kitchen sink water is known as black water. see Recycling grey water treatment can remove these problems. See Waste recycling
The other important way of preventing drains and sewers overflowing is SUDSSustainable urban drainage systems