This is the weekend when the Bitterroot River gets a little "housecleaning service." The annual Bitter Root Water Forum "Bitterroot River Clean-Up and Riverfest" is underway. Already, people have volunteered to walk the banks or float portions of the valley's main waterway and pick up trash. Then, on Saturday, August 14, much of that refuse is collected at a huge dumpster at Hamilton's River Park. And then Saturday afternoon, Riverfest happens at 5 p.m. - music, food, fun and an adult beverage or two.

It climaxes three days of water forum events that started Thursday with a Pint Night at Higherground Brewery, with a portion of the sales going to the forum. Friday evening is the "Run for the River 5K" run/walk beginning and ending at River Park, next to Haynes Field in Hamilton. Registration is still happening at $40 each (which includes a cool Water Forum Hydro Flask). The route takes you through a couple of Hamilton's riverside parks, so be ready for cross-country type surfaces. And, there's a route for those who have strollers. That run starts at 7 p.m. Friday, immediately after the popular "Splish Splash Dash" for the youngsters at 6:45 p.m. at the park. You don't need to register for that short course - just be ready get a little wet.

Katie of the Bitter Root Water Forum said the Riverfest is a way to gather with others who really care about the Bitterroot River and want to keep it healthy. The party includes the local group Pinegrass, beer from Bitterroot Brewery and a special food truck from Stevensville. You need more information? Check here.

LOOK: Stunning vintage photos capture the beauty of America's national parks

Today these parks are located throughout the country in 25 states and the U.S. Virgin Islands. The land encompassing them was either purchased or donated, though much of it had been inhabited by native people for thousands of years before the founding of the United States. These areas are protected and revered as educational resources about the natural world, and as spaces for exploration.

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