During most of the year you will cross water many times during the day along the OHT. Consult the guidebook for the exact locations. In the drier months (July – September) the water can be hard to find, but not impossible. If you are planning an end-to-end hike of the OHT during these months it is a good idea to stash some water along the route, just in case. Generally speaking the water along the OHT is clean and relatively pollution free. However, it is advisable to treat ALL water that you consume from any unknown water source – most folks use water filters, but boiling is OK too, just more of a pain.