"Gravel extraction in the Portage Valley has been a common practice dating back to the 1960's. The quality of gravel found here is beneficial to railroad and highway repairs as well as development of local homes and businesses. By working closely with contractors, the Forest Service has converted remaining "gravel" pits into rearing ponds for juvenile salmon and char. Channels have also been created to connect Portage Creek with these ponds to provide access for juvenile fish and additional spawning habitat for adult salmon. Since these artificial channels often lack the complexity needed to provide valuable fish habitat, materials such as trees, rootwads, and boulders are added to provide cover for fish, create more pools and riffles, and give the channel a more natural appearance." — USGS placard, as seen on the right
The channel that connects the ponds to Portage Creek is over 1.5 miles long. It consists of a man made portion that originates at the outlet of the first pond. The remaining 3 ponds drain into the channel that connects downstream to a natural channel that drains into Portage Creek. Various portions of the natural channel have been enhanced for salmon spawning habitat. The four ponds provide an estimated 9 acres of fish and wildlife habitat, and the entire channel is listed in the Anadramous Waters Catalogue of the ADF&G. The constructed channel and ponds support self-sustaining runs of sockeye, chum, pink and coho salmon in addition to being home to arctic char, waterfowl and various terrestrial mammals. The channel is a popular spot for viewing salmon spawning in the late summer. Miles of nature trail have been established throughout the area and are a popular for hiking, camping and other outdoor activities.