The Guernsey Trees for Life team is planting trees at the reservoir.
The charity is planting native and neutralised species, such as English oak, Hawthorn, Field maple and Crab apple, in the hope they will contribute to local wildlife.
It is all part of GTFL's 2022 planting programme, which has already seen the team plant saplings at Le Murier, La Houguette and Scouts HQ at Rue Mainguy.
The initiaive is being supported by Channel Island Fuels, which is donating to the charity for every litre of petrol sold at St Martins and Jeffrey's garages.
Anyone interested in volunteering to help plant trees, offering their land for tree planting or making a donation to the organisation can contact GTFL on gsytreesforlife@gmail.com.

Firefighters tackle gorse fire at La Corbiere
50 people evacuated from scene of fire in Portbail-sur-Mer
'Pause before paying' to avoid being scammed, islanders urged
Five Guernsey firefighters injured while travelling to assist with Sark fire
Emergency response to fire on Little Sark
Hospitality sector calls for Guernsey's States to make savings before GST
Bailiwick's underwater wonders highlighted on new stamps
"Heightened risk" of wildfires in Guernsey