Most of the time, a flood-control dam is the least interesting thing in your county. It’s a long grass hill with a lake on one side, a parking lot, a boat ramp, and a sign telling you not to swim. Omaha has four of them, built by the Army Corps of Engineers after a pair of storms in the mid-1960s flooded parts of the city, and most people who jog around Zorinsky or Cunningham probably couldn’t tell you what the hill is for.<\/p>\n
On the night of September 30, the hills earned their keep. A two-day storm dropped 4 to 8 inches of rain on the Omaha area, and all four of the Corps’ Papillion Creek dams pushed their lakes to the highest levels ever recorded at each one.<\/p>\n
Zorinsky went 2.1 feet past its old record. The other three cleared theirs by between about four inches and a foot.<\/p>\n
Then the Corps let the water back out slowly, sent people to walk the dams and levees, and on October 21 published the numbers. So how close did Omaha actually come?<\/p>\n
The Corps’ Omaha District runs 14 dams across the Papillion Creek basin (Omaha) and the Salt Creek basin (Lincoln) as one system. The four in Omaha are Cunningham, Standing Bear, Zorinsky and Wehrspann, and you probably know them as lakes rather than dams, because that’s the side you see. Here’s the Corps’ own table of peak elevations from the storm, against the previous record at each lake.<\/p>\n
Those record and previous-record numbers aren’t mine. They come straight from the Omaha District’s October 21 release<\/a>. The normal-pool figures and the “feet above normal” math are mine, pulled from the Corps’ daily Papillion Creek bulletin<\/a>, and I’ll explain why that matters in a second.<\/p>\n Zorinsky jumps out. A 255-acre lake rose almost nine feet above where it normally sits, and more than two feet past anything the dam had seen before. Omaha’s KMTV reported the margin as “nearly three feet” in the days after the storm, and I’d go with the Corps’ table over that, since the Corps is the one holding the gauge.<\/p>\n If you’ve never looked at a reservoir bulletin, those elevations can look like the dams are over a thousand feet tall. They aren’t. The figure is the elevation of the water surface above a fixed datum, basically a height above sea level, and every lake has three lines that matter.<\/p>\n There’s the normal pool, where the Corps keeps the lake on a regular summer day. There’s the flood-control pool, which is the top of the storage the dam is designed to hold back. And there’s the day’s reading.<\/p>\n I ran the storm peaks against the bulletin, and you get a decent sense of how much room was left. Zorinsky’s flood-control pool tops out at 1,128.2 feet, so the record 1,118.9 feet left about nine feet of designed storage unused.<\/p>\n Cunningham’s flood pool goes to 1,142.0 feet against a peak of 1,125.6. Standing Bear tops out at 1,121.0 against a peak of 1,109.8, and Wehrspann at 1,113.1 against 1,104.2.<\/p>\n So the lakes set records and still sat comfortably inside the pool they were built to fill. That’s pretty much the best outcome a flood-control dam can have, and frankly it’s the outcome nobody writes about, because nothing broke.<\/p>\n One thing I can’t give you is the height of the embankments themselves. The Corps release doesn’t list it, and I couldn’t find a clean figure in the district’s own planning reports either, so I’m not going to guess.<\/p>\n What the reports do give is the size of the creek each dam catches: Cunningham drains 17.8 square miles, Zorinsky 16.4, Wehrspann 13.1 and Standing Bear 6. Which probably helps explain why Standing Bear, the smallest catchment of the four, climbed the least.<\/p>\n The other ten dams in the system sit around Lincoln, about 50 miles southwest, on the Salt Creek side. Branched Oak, Holmes Park, Pawnee, Twin Lakes, Conestoga, Yankee Hill, Blue Stem, Stagecoach, Olive Creek and Wagon Train. The Corps says their levels “rose substantially” in the same storm but stayed under their previous highs.<\/p>\n Why the difference? The release doesn’t say, and I’d rather not pretend to know exactly where the heaviest rain bands landed.<\/p>\n The 4-to-8-inch range covers the whole event, and a storm that puts 8 inches on west Omaha and 4 on Lincoln would produce more or less what the tables show. That’s my read of it, not the Corps’, so treat it that way.<\/p>\n The dollar figures back it up either way. The Corps models each flood twice, once with the dams and levees in place and once as if they’d never been built, and calls the gap in damage to homes, businesses and public infrastructure the “damages prevented.” For this storm the Papillion Creek dams get credit for $17.55 million and the Papillion Creek levees for $13.74 million.<\/p>\n The Salt Creek dams come in at $394,000 and the Salt Creek levees at $964,000. Add it up and you get $32.6 million, which the Corps rounds down to “an estimated $32 million” in its headline.<\/p>\n Filling a flood-control lake is only half the job, and it’s the easy half. The other half is getting rid of the water without sending it downstream all at once, which would just move the flood a few miles east. The Corps says the impounded water “was gradually released following the storm,” and that it had people out checking on the dams and levees while that was happening.<\/p>\n “No significant issues were identified,” said John Benson, the Omaha District’s engineering division chief, in the release. The district says the next step is a post-flood assessment across the whole system and whatever repairs come out of it.<\/p>\n By the morning of October 27, the bulletin had all four lakes within a foot of their normal pools again. Zorinsky was at 1,110.58 feet, about seven inches above where the Corps likes to keep it.<\/p>\n As for the neighborhoods, John Winkler, general manager of the Papio-Missouri River Natural Resources District, the local partner that runs the lakes day to day, told WOWT<\/a> there was “some lowland flooding” and some roads under water near the creeks, plus a shelter at Wehrspann that nearly went under. That’s a long way from the scenes that got these dams authorized in the first place, when a single storm in the mid-1960s killed seven people in the Papillion Creek watershed.<\/p>\n You might be reading that number as a repair bill or a check somebody wrote, and it isn’t either. It’s a modeled estimate of damage that didn’t happen, and the Corps is fairly upfront that the models compare a simulated flood with the structures in place against one without them.<\/p>\n Nobody got $32 million. Some basements in west Omaha just stayed dry, probably quite a few of them.<\/p>\n The same release tabulates what the system has prevented since it was built, in today’s dollars: $84.96 million for the Papillion Creek dams, $192.39 million for the Papillion Creek levees, $399.36 million for the Salt Creek dams and $409.68 million for the Salt Creek levees. That’s a bit over $1 billion in avoided damage, and this storm added about 3 percent of it in two days.<\/p>\n If you’re wondering how that stacks up against the bigger dams we’ve covered lately, like the 726-foot dam on the Colorado River<\/a> with its turbines at risk, the 162-foot earth dam in southwest Colorado<\/a> that took on the leftovers of three Pacific hurricanes this month had the opposite problem, filling fast enough to put the homes above its lake on pre-evacuation notice. The Omaha dams filled faster than ever and still had nine feet of designed storage to spare at the worst of them.<\/p>\n Different scale, same basic idea, and in Omaha’s case it’s a lot easier to picture, because the “dam” is the hill behind the boat ramp. The Corps’ Omaha District put out Release 26-026 on October 21, 2026, with the four record elevations and the $32 million estimate, and its daily Papillion Creek bulletin for October 27 shows all four lakes back within a foot of their normal pools.<\/p>\n","protected":false},"excerpt":{"rendered":" Most of the time, a flood-control dam is the least interesting thing in your county. It’s a long grass hill … <\/p>\nWhere does a number like 1,118.9 feet even come from?<\/h2>\n
The Salt Creek dams got the same weather and didn’t break a record<\/h2>\n
The water went back out slowly<\/h2>\n
You can’t cash the $32 million<\/h2>\n