Outdoorsy types understand the need for hydration, but it’s a pain to lug large quantities of water with them on their adventures and water filters can be bulky. 

A company called Tortoise Gear has launched a kickstarter campaign to fund their smart solution to this dilemma: a drink reservoir system that uses the power of the sun to remove most of the bacteria and viruses from water you find along the trail. That’s right. No more filters, batteries or chemicals.

Sol Water uses the solar water disinfectant (SODIS) system that converts UV rays from the sun to kill bacteria and viruses in as little as three hours during peak sunshine. The reservoir is reusable and can even be frozen. The bags are lightweight and durable, washable and marked with detailed instructions about the solar purification process.

Sol Water comes in three sizes. The Survivalist model is a one-liter bag capable of carrying boiling hot water if necessary. The Day Tripper model also has a one-liter capacity, but has a built-in pop-up drinking spout. The Backpacker model is a two-liter capacity reservoir specifically designed for hydration backpacks. All three models have reflective markings to speed up the purification from the sun and are marked with measurement lines to indicate the amount of water left. 

How do you know that the sun has done its work and the water is safe to drink? The Sol logo on the reservoir has a sun symbol to watch: until the arms of the sun can be clearly seen, the water is likely too cloudy to use. Because Sol reservoirs don’t contain a filter, any debris in the water will remain and won’t be purified.

Tortoise Gear’s kickstarter campaign is looking for pledges as low as $3 for  the Survivalist model, and offering a three-pack of all models for a $27 pledge. If the campaign provides the expected funding, Sol Water will be in the market early next year.

It’s a simple and practical system that has the right size and weight to carry in a backpack when you head out on the trail, and a handy item to keep in your home or car as part of your emergency gear.