The duty of handing over a last drainage & wastewater control plan for the United Kingdom Executive in 2023 has been made more straightforward for South West Water by means of the use of complex asset funding control instrument, bettering long-term making plans functions, says Andrew Gibson of ICS Consulting

In a primary for the English water sector, utilities are being requested to supply drainage & wastewater control plans (DWMPs) by means of Defra.
Ultimate DWMPs are due in spring 2023 with the aim of creating long-term plans to evaluate long term lines on drainage and wastewater networks from the consequences of a converting local weather, inhabitants enlargement, and larger urbanisation.
The plans are anticipated to be public-facing and similar between corporations. They’re additionally, partly, a reaction to stricter efficiency objectives, converting executive law, and larger public scrutiny of blended sewer overflows (CSOs) liberating sewage and stormwater into rivers and seas all through heavy rainfall.
With a making plans horizon of 25 years, DWMPs permit better working out of sewer and wastewater community resilience and should reveal very best price for funding. To facilitate the 25-year horizon, adaptive making plans must be integrated permitting processes to be iterative, versatile, and regularly evolve as new information, parameters, and comments come to gentle.
To reach a very best price and adaptive DWMP, South West Water (SWW) has used powerful making plans gear that have enabled it to succeed in the stern submission time limits. Operating in collaboration with specialist asset control consultancy ICS, SWW has deployed the complex asset control optimiser device Asset Funding Supervisor (AIM) from Probit to steer funding decision-making.
The usage of AIM, SWW has evolved a making plans framework that produces menace maps of crucial belongings akin to pipes, pumping stations, and remedy works; investigations into the capability of the drainage and wastewater community; prioritised places for funding; and most popular intervention methods.
Interventions range from gray infrastructure answers, akin to further garage tanks, culverts, and increasing present wastewater networks and remedy works, to nature-based sustainable drainage answers (SuDS), together with rain gardens, retention ponds, and wetlands.
Ben Ward, head of efficiency and innovation at SWW stated, âThe problem for South West Water for its DWMP is to guage some great benefits of other funding choices when making improvements to its drainage and wastewater techniques â taking into account the commercial, societal and surroundings advantages inside the long-term supply technique trade making plans processes.â
Difficult questions
SWW has evolved its draft DWMP over the path of 5 years, since 2018, when the reputable DWMP framework was once revealed. Operating with the twenty first Century Drainage Programme, a cohort of over 40 organisations together with executive regulators, cross-sector corporations, lecturers, native government, and environmental charities, SWWâs DWMP goals to respond to the questions:
⢠What’s the capability of the drainage community? How a lot more is wanted to verify resilience with a converting local weather?
⢠How can new investments be assessed to make a decision which is able to give you the largest get advantages?
⢠How can consumers be helped to grasp what can and can not pass down bogs and sinks into the sewer community?
⢠How can selections on drainage investments and interventions be higher defined to stakeholders?
⢠How can drainage be made more effective and extra constant for all stakeholders concerned?
SWW has 653 catchments outlined by means of the geographical house served by means of each and every wastewater remedy works. To permit a complete community making plans procedure, the ones catchments had been grouped into 22 better catchment spaces. ICS labored collaboratively with wastewater asset managers and strategic coverage team of workers from SWW, the use of Probitâs AIM instrument, to create a making plans framework throughout all 22 catchments.
The staff gathered information for the dangers and attainable interventions to be had and used it to generate a sequence of interventions, along related prices. Those situations printed the impact of taking a âdo not anythingâ baseline place and the diminishing dangers related to other funding selections.
Drainage lifecycle
The usage of the AIM platform, SWW can type all the lifecycle of drainage and wastewater belongings, expecting adjustments, and the way they’ll have an effect on on products and services. This leads to higher decision-making for extra resilient belongings and diminished carrier disruptions.
AIM too can analyse menace at a granular degree, by means of area and right down to a person asset, permitting SWW to inspect elements akin to making plans constraints and related dangers of no longer starting up paintings at explicit time horizons.
Tim Watson, technical director at Probit stated, âAIMâs biggest energy lies in its skill to answer the unknown and broaden accordingly. It has a prime degree of adaptability and versatility when shoppers are dealing with new necessities, such because the evolving DWMP procedure.
âIt may be used to respond to bespoke and sophisticated questions for SWW relating to intervention variables and comparisons, and is optimised to try this hastily.â
Luke Ferriday, senior marketing consultant at ICS stated, âAIM is used methodically by means of initially figuring out the dangers inside of a catchment, then asking what the price implication could be from a spread of interventions. The best way that influences the chance degree is then printed.
âMaking plans situations will also be mapped iteratively to totally perceive the results of more than one attainable selections in hours, no longer days.â
SWWâs draft DWMP was once launched in September 2022 and the application now understands the making plans situations, interventions, and implications for its 22 catchments. This implies the making plans staff can now examine and revisit the situations and constraints inside of each and every catchment as new information and comments come to gentle for its ultimate DWMP. Constraints come with finances, CSO and flood-risk objectives, prime precedence websites liable to flooding, intervention sorts, and implementation timescales.
Eventualities are simply analysed thru AIMâs centralised dashboard with configuration gear enabling SWW to report to interior stakeholders successfully. Bespoke stories may also be generated in AIM which can be utilized to have interaction with exterior stakeholders and consumers.
If executive law, trade or efficiency objectives exchange someday, SWW has a device that may readily assess have an effect on on asset well being, efficiency, and value. The problem dealing with SWW, now that making plans situations are absolutely understood, is number of an optimum pathway of attainable funding for the general DWMP, which gives consumers, communities, and the surroundings with the best advantages for a resilient long term.
Recently, this can be a new box of inquiry for the English water sector, and long-term analysis and research of those variables is most effective starting. Nature-based interventions have the prospective to ship a step-change in drainage and wastewater control however, because of vulnerable working out and a loss of proof, they incessantly display as the dearer intervention in comparison to conventional gray infrastructure answers.
AIM is an instance of efforts underway to make asset control extra powerful and complex. The hope is that nature-based interventions will also be higher understood and additional built-in into making plans processes now and someday.