Why sand dams Other solutions we deliver Rock catchments Rock catchments Rock catchments utilise the surface run-off of water from flat rocky outcrops on hilltops. By building channels around the rock, rainwater is guided into a pipeline that supplies one or more water tanks. Since 2002, Excellent has supported communities to build 12 rock catchments, with each one able to collect up to 104,000 litres per tank for domestic use. Could you donate today and supply more communities with the tools, hardware, support and guidance they need to transform their own lives with lifelong access to clean water? Please select a donation amount: * £15 could provide a farmer with drought-resistant seeds, so they can feed and support their family. £30 could supply a community with a rake, gardening fork, shovel and watering cans, to plant trees for fruit, fuel and fodder £60 could provide a roll of barbed wire to reinforce a sand dam, anchoring it to the bedrock. Other Set up a regular payment Donate