Amid a field of “zombie willows” in the Kawuneeche Valley within Rocky Mountain National Park, researchers and water providers are taking lessons from nature’s ecosystem engineers to build drought resilience and restore wetlands. … The Kawuneeche Valley exists just downstream from the Colorado River headwaters. … “A healthy and functioning wetland is a sponge,” said Jeremy Shaw, a research scientist with Colorado State University who has led wetland and stream restoration efforts in the valley. “It is a fire break. It is a drought resilience machine. It is a water quality plant. It’s a water treatment plant. So healthy, functional wetlands, particularly ones that support beavers, trap sediment nutrients, output clean, reliable water. It also slows down and spreads out the water.”