It's Alive! Modeling Lifecycle Through Model Maintenance

Purpose: This presentation will be on the modeling lifecycle whether stormwater or collection system. From having no model to building your first hydraulic model all the way to having a model maintenance program. This will be done by looking at the four main phases of the process including example on how those phases can be used to deliver stormwater improvements. Benefit: Many presentations on hydraulic modeling whether sanitary, stormwater or combined system show the completed model and the work that was involved in developing the model. Some even show the outcomes and uses of those models. However, few show the solutions available to a municipality to resolve issues when they have no model and how that can set them up for modeling in the future. In addition, committing to building a model can be challenging and getting buy-in even harder so this presentation will show an example of dipping your toes in through a pilot project. Finally, on top of all this the presentation will show a models greatest benefits, and that if a model can be kept alive through model maintenance it can be used for the years to come increasing its cost benefit ratio the more often and longer it gets used. Phase 1: Known issues but no model. Determining long term goals and prioritization criteria So, you have issues in your community, how do you prioritize projects? Many communities don't have a model and only have GIS information to use to determine which projects to prioritize. AtkinsRéalis (then Atkins) was hired to develop a prioritization strategy for the Henrico County's selected drainage improvement projects based on GIS data. (Project Completed) We aided them in determining long-term goals and identified and filled data gaps. Based on these we developed a Microsoft Excel-based tool shown in Figure 1 and an approach to aid in prioritizing their drainage improvement projects. This tool and approach to prioritizing projects has been rolled out to multiple municipalities across the country. Using this information these municipalities prioritized their projects and are getting them to the design phase. Critically, this phase is necessary towards making the most out of a model to determine long term goals and assessing what data a municipality wants out of a model to prioritize with. Phase 2: Building a model. Benefits and easing in with a Pilot Model. Now if you have your long-term goals and can prioritize projects based on GIS and public outreach why would you create a model? The benefit of a model is that instead of just knowing where there are issues a model lets you know why, when, and how those issues are happening. Often those are some of the most important criteria you want to prioritize with. Even then it can be hard to commit to modeling, but it is possible to get a taste by running a pilot project. Case Study: City of Baltimore, Maryland (Completion Spring 2025) The City of Baltimore (City) hired AtkinsRealis, as part of a joint venture, for a pilot project to develop stormwater models for three of the city's watersheds. The project involves: - Writing a modeling handbook for future modeling -Defining flooding criteria based on local regulations - Determining flooding issues based on criteria - Developing, testing, and cost estimating solutions to these issues Phase 3: Model completed and in use. How can you use it for your long-term goals and future issues? You now have a working and accurate model. Great what can you use it for? Here's an example: Case Study: City of Baltimore, Maryland The City and community on Wyndurst Avenue, believed the flooding was due to insufficient culvert capacity. However, the model showed that although the culvert was under capacity so was the stream upstream of the culvert. Thankfully, the model has allowed the City to weigh numerous options shown in Figure 2 and determine a path forward. Phase 4: Model getting old. How can you keep using it long-term You've been loving your model. Now the question comes up is it good forever or does it have a 'Best if used by' date? Models do get outdated as CIPs are implemented, communities grow or shrink, and the climate changes. To keep using a model a model maintenance plan will need to be implemented to keep the model accurate. Case Study: Scottish Water, United Kingdom (Completed) Scottish Water tasked AtkinsRealis, as part of a quinquennial framework, to update the Inverclyde Council's combined sewer model into a 1D-2D integrated model. This was one of numerous model updates that has occurred throughout the past few decades. Each iteration of the model has helped Scottish Water target issues more precisely as well as keep up with the population and impermeable surface growth throughout the years. The model has allowed the utility to pre-empt climate change and development issues. In 2024, Scottish Water completed construction of a Combined Sewer Overflow on the main road resolving years of flooding and spilling issues as shown in Figure 3. Conclusion: It might seem daunting to get into modeling but a model can truly benefit your community and help you reach your long-term goals. So really the question is can you afford to not have a model? It's good to fix flooding and spilling issues but how much better is it if you can know that you will be fixing the issue correctly the first time. Modeling is cheaper than digging.