By Stephen Drinkwater
It’s not often we can say that adverse weather is a good thing, but following a recent project completed with Seymour CEC, myself and the Lynas team have been able to see the longer term impact of innovative management and collaborative working – especially poignant given our rapidly changing environment.
Lynas Engineers were commissioned by Yorkshire Water, through Seymour CEC, to provide a stormwater storage design capable of increasing the total stormwater storage capacity of the site to 395m3 at Easingwold Sewage Treatment Works (STW) in York. This project marked the first of thirteen STW sites we had been requested to provide stormwater storage design proposals for, and it was actually the first of its kind that we had been invited to design for!
It was fascinating to get into this project – working on an optioneering report to detail the potential stormwater storage expansion options available to Yorkshire Water and concluding that our designs needed to incorporate an additional 55m3 of stormwater storage to be effective. Our recommendations provided this solution that also ensured the most cost-effective solution for the client too. Whilst we consistently focus on delivering the most impactful, innovative designs, we are conscious of the need to remain within the parameters of each project too – so this project challenged us the best, most varied ways.
As with most projects, we encountered some challenges during the design phase. We maintained the top water level of the existing tank to ensure the design head at the existing storm tank would not be increased. To ensure the new storm tank could be constructed within surrounding site constraints, Lynas Engineers proposed to install the new tank in the location of the existing storm tank inlet pipe and cut back the pipe either side of the new tank walls to form its inlet and outlet pipes. This proposal also maintained the inlet pipe supplying stormwater to the existing storm tank. The base of the new storm tank featured a slope benching to direct flow into the existing storm tank and a 1m diameter x 1.5m height CWF flushing bell was specified to provide tank cleaning and reduce future maintenance costs.
In May 2024, this project won the Yorkshire Water Cabron ‘Project Initiative’ Award, through Seymour CEC, after a remarkable total carbon saving of 68,397kgCO2e was achieved following design optioneering, design optimisation, hydraulic profiling, manufacture and assembly. I, and the whole team are remarkably proud of our significant involvement in the design of an awardwinning new storm tank, and knowing that our unique ways of working – utilising innovative thinking and working with clear, open communication with the client – has given rise to a better understanding of the stormwater tank storage and its benefits is fantastic. Knowing how we can keep responding to the changing climate, and monitoring its impact on our communities is one of the most challenging, yet important elements of our work. We know our world is changing, but now we need to be working together to monopolise new ways of working to ensure we can change alongside it too.
In addition to working with Seymour CEC, our team worked in collaboration with FP McCann, Eliquo Hydrok and Yorkshire Water – thank you for being great partners to work with.
Want to learn more about Lynas Engineers, how we work and the solutions we can provide? Visit www.lynasnegineers.com for more information.
