How we’re saving water

Maintaining 11 Premier League match-quality pitches takes a lot of water, and during the long hot English summer – when the pitches are being renovated and pre-season training gets underway – there is a huge demand for irrigation. And we are proud that the training ground at London Colney, home to the first team, Women, Under-23s and Under-18s, has a water recycling system to help reduce the amount of mains water used on the pitches.

During pitch irrigation the water runs off the grass and into topsoil, where it is absorbed by the grass roots. The water that doesn’t reach the roots will run away elsewhere and be wasted, however we have installed a system where we are able to channel this water into a network of underground pipes. These pipes carry the water into a large underground reservoir, which is four metres deep and capable of holding up to two million litres of water!

Installed back in 2011, we can harvest between 15 and 20 million litres of water every year this way.

As well as the water from the pitches, rainwater from the rooves of most of the other buildings around the site is also collected and ends up in the irrigation tank, although rainwater from roads and paths isn’t collected to ensure no contaminates enter the water system and damage the lush grass.

During the journey into the tank, the water passes through a separate filtration system to remove any bacteria and small particle sediments.

The tank is located underground to deprive the water of light, therefore stopping the growth of algae and keeping it in perfect condition. When required, the water can be pumped around the site to any of the pitches or to the surrounding gardens and is also used to irrigate Colney Wood, which is home to the 200 trees that were planted in collaboration with our Energy partner, Octopus Energy.

And we’re saving water elsewhere too. Cleaning all the mowers and tractors is a crucial part of ensuring the pitches and grounds are kept in tip-top condition. 

After ten hours of grass cutting the mowers are returned to the workshop area for their daily clean. Using specialist machinery, the water used in the cleaning process is collected and filtered to remove all the grass cuttings. The machinery also cleans the waste water by using special microbes, preventing any chemicals reaching the main sewerage system. At Emirates Stadium and Hale End, they also use similar systems during the wash-down process. At these two sites, the residue grass is collected and sent away for composting.