Ryan Welsh is Chief Engineer at City of Cincinnati, Metropolitan Sewer District in the USA – at WEX 2020 he is joint chair of the critical session, Improving Energy Efficiency in Water & Wastewater Treatment. This session explores the drive towards carbon-neutral water and wastewater treatment, one of the key areas in which the water sector is combating climate change.
Why do you come to WEX?
“Primarily to get new ideas for how to deal with the challenges we have by learning from people in other parts of the world. Sometimes I see a solution that others have developed and I am able to apply it to something we are working on. It’s also interesting to learn about problems that other utilities are experiencing, but that we might not have, and in some cases to be able offer some new insight from an outsider perspective. I’ve been coming to WEX for years, for this reason – the international discussion and collaboration in such a positive and relaxed setting is invaluable.”
What are you up to in Cincinnati at the moment?
“Over the past ten years our utility has spent nearly two billion dollars upgrading assets and building new wet weather infrastructure such as high rate treatment facilities and stormwater separation projects. We’re under a federal mandate to eliminate overflows and we have much more to do in the coming decade. We are always focused on how to best apply our limited resources to get the most benefit for public infrastructure. In the past several years we have developed a robust asset management program to develop and prioritize projects. In addition, much of our focus has been on how to leverage the latest technologies to optimize existing assets, such as the deployment of remote sensors and controls to minimize sewer backups and overflows, and to maximize throughput in wastewater treatment facilities. We’re endeavouring to build resilient infrastructure for less predictable conditions – we are seeing increasingly intense rainfall events, more frequently, and this is becoming a problem.
What about the circular economy?
“The mayor of the City of Cincinnati is leading an initiative to reduce our reliance on fossil-fuel derived electricity and has recently entered into an agreement to install enough solar power capacity to coverage peak electrical usage of all the City’s assets within the next three years. The 20-year agreement is the biggest solar power commitment made by any US city to date. Since the water and sewer utilities are the City’s largest consumers of electrical power, this is going to push us to move towards more sustainable and creative methods. I think we will be seeking to reduce electrical consumption during the part of the day when the sun isn’t shining, so implementation of energy storage and conversion technologies will become more attractive. In addition to some other ongoing utility-led initiatives that will reduce energy usage, we are currently working with APG-Neuros to implement a technology that would allow our aeration blowers to operate without the use of electrical power, and to eventually power our blowers with digester gas. Since the aeration process is the most energy intensive treatment process, this will have a big impact.”