{"id":120972,"date":"2023-02-09T12:37:55","date_gmt":"2023-02-09T12:37:55","guid":{"rendered":"https:\/\/www.pbctoday.co.uk\/news\/?p=120972"},"modified":"2023-02-09T13:57:55","modified_gmt":"2023-02-09T13:57:55","slug":"smart-technology-repurpose-legacy-drainage-assets-battle-against-flooding","status":"publish","type":"post","link":"https:\/\/www.pbctoday.co.uk\/news\/planning-construction-news\/smart-technology-repurpose-legacy-drainage-assets-battle-against-flooding\/120972\/","title":{"rendered":"Using smart technology to repurpose legacy drainage assets in the battle against flooding"},"content":{"rendered":"

One of the most significant impacts of climate change will be increased flooding incidents. To reduce the impact of flooding on people and the environment, we need to repurpose our legacy drainage assets and focus on low carbon intervention, says Brian M Back, co-founder and CTO of Radio Data Networks Limited<\/a><\/h2>\n

Indeed, we see countless pictures of major pluvial flooding<\/a> on media feeds almost daily. However, for every large incident caused by a major river, there are hundreds if not thousands of smaller unreported \u201cother flooding\u201d incidents associated with drainage and linked to rainfall that potentially collectively impact more people and cause more damage to the environment.<\/p>\n

Sewer flooding incidents can be more damaging than pluvial flooding<\/h3>\n

Many of these \u201cother flooding\u201d incidents are actually reported in statistics published by governments. For example, in England, the Environment Agency<\/a> collect and publish figures under categories such as CSO (combined sewer overflows) spills, sewer surcharges, and sewer flooding incidents. Combined, these figures equate to half a million incidents in England alone.<\/p>\n

Surcharges or sewer flooding incidents, of which there are tens of thousands annually, as the author can testify from first-hand experience, can be devastating and equally if not more damaging than pluvial flooding.<\/p>\n

The largest figure, however, is for CSO overflow spills. The irony is that the presence of CSOs is to reduce the incidents of sewer flooding, but in reality, the flooding is simply moved to a\u00a0 local watercourse officially called the receiving water, be it the sea or a stream or brook and converts a flooding incident into a pollution incident too.<\/p>\n

What is often forgotten is the consequential impact of any CSO spill, as not only are they likely to increase the risk of pluvial flooding downstream but also, they are the transport mechanism for not just sewage but long-term pollutants such as hydrocarbons and plastics that enter our environment.<\/p>\n

To combat sewer overflows, we need to tackle the root cause<\/h3>\n

The common denominator in all these figures is sewers, particularly the combined sewers. A Victorian legacy but actually the Romans made them too, some of which are still in service. These are gravity sewers that take both sewage and rainfall away from our built environment in a \u201ccombined\u201d single pipe.<\/p>\n

To combat these overflows, we need to tackle the root cause – rainwater. Building regulations have in recent years gone a long way to addressing this issue for new builds, where now housing, highways, and commercial developments have to use SuDS<\/a> and NFM, but this doesn\u2019t address the legacy.<\/p>\n

Flooding is not about the volume, but peak flow management<\/h3>\n

Normally sewers have adequate capacity to cope with their normal load plus a considerable loading from rainfall. Setting aside incidents caused by blockages, it is the peak flows that cause the majority of incidents of flooding and pollutive spills. Hence incidents are often linked to heavy rainfall.<\/p>\n

Traditionally flow management techniques include:<\/h4>\n