TECUMSEH – Nemaha NRD Manager Bob Hilske says flood control structures in his district decreased the severity of flooding along the Little Nemaha River, but were not designed to control the type of flooding that beset the state this spring.
He said 350 dams control water on all the district’s watersheds, but they are designed based on actual water flow, rather than the deep frost that lingered late into March and ice jams.
Hilske: “Typically it’s going to be the moderate type event, which is a lot smaller than the boundaries that we were facing with this kind of a … this is a once-in-a-lifetime type event. It’s kind of a perfect storm of run-off, snow melt, ice and that’s what really contributed to all the problems. It’s not that often that you have that kind of a mix all put together to create what we had today and it’s really problem something that would be very difficult to plan for and prevent, even if it happens again in the future.”
There were no days with temperates above freezing in the first two weeks of March and only precious few hours of thawing before springs rain began falling.
Hilske: “We were very successful down here. We actually went around and monitored a lot of our structures. After the snowmelt started happening, we were getting the rain. Typically, what we saw was in the northern part of our district — the Palmyra, Bennett, Firth area – we did see a lot of runoff up there. Those structures filled. We had a lot of flood storage in those reservoirs and they held up perfectly fine. “
The southern and central portions of the district had less snowpack and did not fill NRD reservoirs around Tecumseh and Falls City.
Hilske: “We feel like it’s been very successful – most smaller watersheds in our district are controlled.”
He said Duck and Buck Creek dams near Peru are among the last of the major watershed dams proposed by the NRD, which is now focusing on maintenance of the structures. Most are 25 to 50 years old.
Hilske: “If we would not have the flood control structures that we have in place today, you would see a lot more flood damage. You would see more flooding in farm land, along streams. You would probably see a lot more county bridge damage and you might even see flooding in some of the smaller communities.”
He said the district even appears to have little damage from the ice.
Hilske: “It’s a lot of why we have flooding in Nebraska because we had such heavy ice pack on our lakes. We had 12 to 14 inches of ice and that hadn’t all melted yet, so we had been looking for any structural damage to our recreational facilities and that sort of thing. We did have one dock at Kirman’s Cove that was significantly impacted by ice damage. Other than that everything seemed like it fared well.
Hilske said the extent of damage to Steamboat Trace is still to be revealed as floodwaters recede.
Hilske: “Steamboat trace was heavily impacted by the flood because it’s right along the Missouri River. We just have started assessing the damage. We can not access the entire trail yet. So far, I think we’ve looked at about half of the trail and what we’re seeing is a lot of debris. The good news is, so far, what we have looked at, we’re not seeing a lot of damage to bridges, where we cross streams or erosion to trail base.”
Area between Peru and Brownville area not inspected because still under water.
