The risk of urban flooding is increasing in Europe as a result of climate change and urbanisation. Urban flooding causes property damage, health risks, and economic disruption and is a threat to the natural environment. In urban areas flooding commonly occurs when the local...
The risk of urban flooding is increasing in Europe as a result of climate change and urbanisation. Urban flooding causes property damage, health risks, and economic disruption and is a threat to the natural environment. In urban areas flooding commonly occurs when the local sewer network is incapable of storing or conveying the runoff from rainfall during and after intense storm events. A typical response for water utilities would be the construction of sewer storage structures or sustainable drainage systems (SuDS). These responses are costly and constrained by economics and local land use policies.
The CENTAUR (Cost Effective Neural Technique to Alleviate Urban flood Risk) project aims to alleviate urban flood risk by more effectively using the existing storage volume in sewer networks and hence provides a significantly less costly solution. This innovative and adaptable technology works by controlling the flows in sewers with a Flow Control Device (FCD) which is operated by a local monitoring and control system (LMCS). The LMCS is driven by an Artificial Intelligence (AI) algorithm that uses live measured water level data to make control decisions. It operates autonomously and on a local level using locally collected in-sewer water level data to deliver flood risk reduction. Previous real time control systems have been centralised, large, complex and costly and have been applied to sewer systems over a wide area.
The project webpage provides an overview of the project, describes the current progress and outlines the potential for the technology. The CENTAUR consortium is composed of three university / research institute partners, two small to medium sized enterprises (SMEs) and two water utilities.
The work performed by the CENTAUR partners in the first 18 months has been related to the development of different sub-systems and their integration into a full scale working system that has been tested in the laboratory and has now been installed in a sewer system managed by one of our water utility partners. The work so far has been split into the following activities.
Development of Local Monitoring and Control System (LMCS) integrated with Flow Control Device (FCD)
The LMCS monitors water levels and uses an AI control algorithm to move the FCD and thus control flows in the sewer system. Different AI approaches were considered and a Fuzzy Logic (FL) based algorithm was adopted. FL is a technique based on the impreciseness associated with human reasoning, rather than deterministic logic, and hence it allows for the input of expert knowledge. The FL algorithm has been developed using computer models and a genetic algorithm code has been written to optimise its performance. The FCD is based on existing, robust technology which has been specially modified for the CENTAUR system. The LMCS has been integrated with the modified FCD to form the overall CENTAUR system. A Failure Mode and Effect Analysis (FMEA) was applied to the CENTAUR system to consider the severity, likelihood of occurrence and probability of detection of potential failure modes and thus allow them to be taken into account in the system design. A web interface to the LMCS allows data to be viewed remotely and also for LMCS settings to be updated.
Testing of the integrated CENTAUR system
A full scale laboratory test facility has been constructed consisting of a 30 m long pipe and four manholes. Pumped flows, controlled by valves provide the ability to produce time varying flows to simulate the effects of rainfall runoff in storm events. The prototype CENTAUR system consisting of the LMCS integrated with the FCD was installed in the test facility. Laboratory tests were performed and the results used to understand how the control algorithm performs in a full scale operational setting. The tests were utilised to further refine the developed FL algorithm and examine the reliability of the integrated LMCS and FCD system. The laboratory results provided a deep understanding of how the CENTAUR system works and proved that it functions as expected and is ready for field deployment.
The sewer network in Coimbra, Portugal which has a history of flooding problems was selected for the pilot installation. The CENTAUR system has been installed in an existing manhole with a water level monitoring point located 300 m downstream. Testing will commence in September 2017 and continue for at least 8 months. The site installation includes a web interface displaying measured data.
Work is ongoing to select a second ‘demonstration’ site in Toulouse, France for testing the next version of the CENTAUR system.
The sewer network simulation studies carried out by the University partners have demonstrated that the CENTAUR concept of using local, autonomously controlled flow control devices can deliver flood risk reduction in existing sewer and drainage systems. The integration of the developed LMCS and FCD has demonstrated that the CENTAUR concept can be technically implemented. A pilot system has been constructed and installed in an existing manhole in the city of Coimbra and field testing is about to commence. Conventional responses for mitigating urban flood risks are costly and disruptive, for example building of individual large underground storage tanks is estimated to cost in the range of €1000 to €1500 per m3 and typically these tanks have a volume of many 100’s of m3. Developing sustainable drainage systems (SuDS) requires collaboration with a range of stakeholders including planners and property owners and can be impractical for water utilities to implement especially in densely populated areas where there are a large number of stakeholders and land availability tends to be low and land costs tend to be high. Implementing the developed CENTAUR technology does not require major new infrastructure or use additional land. A CENTAUR installation will cost significantly less, and be less disruptive than the conventional options.
In terms of impact, the UK government water regulator OFWAT has identified 3644 properties with an unacceptable risk from sewer flooding and that require remedial action from water utilities. Urban flooding occurs throughout the EU, so the overall impact in Europe will involve many thousands of properties. There is therefore a significant market for local autonomous local flow control solutions to be delivered to provide an economic level of flood protection. The CENTAUR commercial partners are utilising their marketing expertise and networks. They have developed a rigorous Exploitation Plan to deliver the CENTAUR system to the EU’s water utilities. From the results of this activity they have estimated that the implementation of CENTAUR in the EU will create around 100 jobs in the involved SMEs and their wider supply chain.
More info: https://www.sheffield.ac.uk/centaur.