The "Mighty Mo," America's longest river, flows past communities in Montana, North Dakota, South Dakota, Nebraska, Iowa, Kansas, and Missouri – plus it receives water from Wyoming, Colorado, and Minnesota. The Izaak Walton League is working with partners throughout the region to make sure this amazing waterway stays healthy. Here's what happened along the river in February.

Basin Runoff Remains Below Average

Runoff into the Missouri River basin above Sioux City continues to be low. January’s runoff was 56 percent of average, due to much-below-average temperatures early in the month and ongoing below-average precipitation. Some areas of Iowa, however, received above-average precipitation in three of the last four months. That precipitation, with unfrozen soil, enabled snowmelt to replenish soil moisture.

The U.S. Army Corps of Engineers is forecasting the 2024 upper basin runoff will be 18.8 million acre feet (MAF). That would be 73 percent of average. On March 1, the start of the runoff season, water in the Missouri River Reservoir System is predicted to be below the exclusive flood control zone.

Drought conditions are expected to persist in areas of the basin into this spring. Mountain snowpack continues to be below average, with the largest snow drought in Montana and Wyoming. In most years, over half of the mountain snow usually accumulates by February 1, with snowpack peaking by mid-April. Learn more.

Corps May Test Ways To Help Pallid Sturgeon

To evaluate if increased releases benefit the endangered pallid sturgeon in the upper Missouri River, the U.S. Army Corps of Engineers may conduct test flows from Fort Peck Dam in northeastern Montana this year. The test will only be conducted if sufficient water is available and if other local criteria are met. The proposed test would include two releases, one in late April and another in early summer.

Biologists want to assess if increased flows attract, retain, and prompt pallids to spawn below the dam. If implemented, test releases would be quickly decreased to examine if lower flows increase survival of newly hatched pallids. The Corps will decide whether they will run the test flows, something that has not been done before, after water levels and other local factors are evaluated this spring. Learn more.

South Dakota Division Comments on Wetland Proposal

Our South Dakota Division submitted comments to the Natural Resources Conservation Service (NRCS) on the proposed DoneGone Wetland Project near the Waubay National Wildlife Refuge in Day County. The area, as other areas of the state, has seen increased conversion of wetland and grassland habitats. The proposed project would restore and create wetlands and establish wetland and upland vegetation on over 122 acres. The site would be protected by a perpetual conservation easement.

In the comments, the Division asked for a comprehensive monitoring period - beyond the stated three years, if needed - to determine if the site’s wetland values are fully restored and if vegetation is successfully established. The Division also requested an adaptive management plan if the project is not meeting performance standards. Finally, the Division asked for a long-term management fund for ongoing maintenance and needed repairs to ensure all ecological functions are met.

Read the Division’s comment letter.

Missouri River Fishing Outlook

The South Dakota Game, Fish, and Parks Department (GFP) hosted a series of informational meetings on the Lake Oahe and Lake Sharpe fisheries. I attended one of these meetings in Pierre on February 20. GFP staff provided information on the history and trends of the two lakes and on future management plans.

In 2023 GFP had the highest number of walleyes in their survey nets in the last seven years. Both Sharpe and Oahe, two of the most popular fisheries in the state, have walleyes in improved condition after several years of slower growth following the 2011 flood. GFP staff said they are preparing for low runoff on the Missouri River this year. The boats ramps on Lake Oahe are expected to provide adequate access to anglers and boaters this summer.

Is There Nitrate in Your Water?

As we move into spring, the League invites you to take part in Nitrate Watch. Nitrate occurs naturally and is essential for plants. However, human activities produce more nitrogen than can be fully utilized. Agricultural fertilizers and manure are the largest sources of this pollution. But residential fertilizers and sewage also increase nitrogen in the landscape. Nitrogen becomes nitrate as it moves through the environment.

Nitrate ends up in our rivers, lakes and streams, the sources of drinking water for millions of Americans. Excess nutrients cause rapid algae growth, known as harmful algal blooms (HABs). The algae dies and decomposes, resulting in reduced oxygen or dead zones that are fatal to fish and macroinvertebrates. Too much nitrate can also adversely affect human health and can be responsible for blue baby syndrome, thyroid disease, birth defects and colon cancer.

Learn more about Nitrate Watch and get your free kit to measure nitrate in your drinking water or your local waterways.

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Top photo: A tranquil day on the Missouri River. Photo credits: Paul Lepisto.