In a newly published report, the House of Commons Environmental Audit Committee has suggested that the rivers in England are ‘a mess’, polluted by a chemical cocktail of sewage, agricultural waste and plastics.
Whilst laying some of the blame at water companies for what the report calls ‘damaging discharges from water treatment assets including storm overflows’, it is also highly critical of other stakeholders including the Government, Ofwat, and the National Highways Agency.
The report also highlights the damage to England’s waterways being caused by the agricultural sector, by climate change and by sewerage infrastructure.
Water companies are tackling this issue and are making progress. This is acknowledged in the report, as it is explained that “monitoring of sewage spills from storm overflows and wastewater plants has improved in recent years as Event Duration Monitors have been rolled out across 80% of outflows on the network since 2015”.
Sewer overflows are used in exceptional circumstances where heavy rainfall is experienced or where there are issues with blockages in the network. One way to tackle their use is to ensure blockages are discovered efficiently and water companies are making huge investments into blockage detection.
Thames Water, for example, has been proactively working on a variety of waste water sewer monitoring projects including sewer depth monitoring (SDM) deployments and the installation of HWM’s new early-warning SpillSens level monitoring and blockage alert system.
On average, Thames Water spends £18 million every year clearing 75,000 blockages from its complex 68,000-mile sewer network and is at the forefront of embracing digital technology to prevent flooding and pollution events.
Discussing the installation of SpillSens, Thames Water Operations Manager Anna Boyles explains that “these new sewer level monitors are the very latest bit of kit – they’ve only just come onto the market”.
“These monitors are an important tool in our armoury in the fight against sewer blockages. The data they provide gives us a picture of what's happening in our sewers and helps us to nip blockages in the bud before they cause problems.”
The investment that Thames Water is making, along with the other UK water companies that are also investing greatly, is paying dividends.
The more regular discovery of blockages, before flooding and pollution events occur, is evidence that early warning systems and real-time data analysis are successful methods for maintaining the smooth operations of this critical infrastructure.