December's final days provide an opportunity to look back on the memories created over the previous year. For hundreds of thousands of us - whether on the field or in the stands on All-Ireland final day or amongst the throngs at Coldplay or Bruce Springsteen - those memories were made within the confines of Croke Park.
Few of us attending those events were aware that Croke Park was embarking on one of the most ambitious sustainability projects of any stadium in the world.
Eighteen months ago, Croke Park embarked on a rain harvesting project on a scale that is unprecedented in this country. The idea was hugely ambitious: what if it was possible to capture all of the rain water that falls from the roof of Croke Park, direct it into a massive tank, filter it, and then use the water to irrigate the pitch at Croke Park?
After eighteen months of work, Croke Park now boasts arguably Ireland biggest water harvesting unit: every rain drop that falls onto the Croke Park roof is to be used to improve the quality of the pitch below.
Previously, the Croke Park ground crew had used potable water to preserve the pitch. Now that water will come from the skies.
We spoke to Colin O'Brien, an operations executive at Croke Park, who was instrumental in making the project happen, from beginning to end. He said it was an 'extremely challenging' process especially considering the business of sport and entertainment that had to happen around it.
The project was the brainchild of Peter McKenna, Croke Park's stadium director. McKenna had had the idea of harvesting Croker's rain water for a few years. But there was one huge logistical issue that needed solving. A massive amount of rainwater would need to be stored somewhere, but storing it at Croke Park was complicated, as space is limited.
The project managers proposed buildnig a tank that could store up to 1 million litres of rainwater for this project, and decided the best place for the tank was eight metres below the ground, beneath where the old Handball Centre once stood.
"When we built a new handball community center there a number of years ago, the old one obviously had to be demolished, so we said that this would be a perfect place now to put the water harvesting tank," O'Brien said.
To make it fit, they had to dig - eight metres deep - into the ground
O'Brien says it's one of the biggest - if not the biggest - water harvesting tanks in the country. It was a 'bespoke' build: made of concrete, custom-built on site, and placed deep into the ground.
"There's essentially a concrete slab over the top of the tank now, and that's essentially going to be used for EV charging. We're going to use it for the bike parking and accessible parking. So people parking there now in the future won't even probably know that there's a tank."
While the water captured is currently used only to irrigate the Croke Park pitch, there's hope that someday it might be used to service the stadium, in areas like the sinks and toilets, but that is phase two for the project.
The firm KSN looked after the project management while HML helped construct the water collection tank. Digging deep into the earth presented its own challenges.
"Obviously when you're digging eight metres deep into the ground, you come across a lot of unknowns, a lot of challenges. That's essentially how deep they had to dig around around eight metres to install the tank, the various filters and pumps that go along with it, all the piping. It was challenging working in a live stadium environment as well.
If you were to come into the stadium now, you wouldn't see anything different or notice anything different, which is insane considering the amount of work that went into it. There was an eight metre deep hole there for a while that covered probably over 500 square meters. So you would have seen that the extent of it during the process and during the construction, but if you were to come into the stadium now, you wouldn't even know there was anything there.
Sustainability is at the core of McKenna's plans for Croke Park.
The stadium is aiming to be net zero by 2050 and is hoping to half its emissions by 2030.
"Peter McKenna, he's a visionary when it comes to sustainability," O'Brien says. "He's always looking to push the boundaries and look for ways to be more sustainable."
This system was fully activated in mid-December, much to the nervousness and excitement of the Croke Park staff.
"You're looking to see, does it actually start to fit our pitch irrigation tank and does it actually work and everything went great, and I think we got a good bit of rain that weekend. It filled up quite quickly and there was no issues, no snags."
There is certainly no shortage of rainwater falling on Croke Park this month. McKenna and his team have now found a way to turn that surplus into an asset for the pitch.
"It should be full most of the year really with the amount of rainwater that we get, but I suppose it also de-risks the operation of the pitch itself, if there was ever to be a drought or issues with water in the area or issues that affected the supply of water into the stadium. We have a backup supply there now because the pitch has to be watered regularly," O'Brien adds.
Imagery courtesy of Sportsfile, GAA.ie and Colin O'Brien
