IOWA RESERVOIR REPORT

Last Updated: December 22, 2025

In Iowa, a recent survey of the state's major dams and reservoirs reveals a mix of conditions as per the latest observations. Storage levels, which are crucial for water supply and flood control, are showing slight deviations from average measurements. Clear Lake at Clear Lake, Black Hawk Lake at Lake View, Lake Panorama at Panora, Spirit Lake near Orleans, and West Okoboji Lake at Lakeside Lab near Milford all exhibit slightly lowered gage heights than their average levels, indicating a possible decrease in water storage. Conversely, Corydon Lake is experiencing significantly higher streamflow rates, while Rathbun Lake near Rathbun is just below its average gage height. These fluctuations could be the result of various factors, including seasonal changes, upstream river flows, and regional precipitation patterns.

Particularly, Corydon Lake's marked increase in streamflow suggests an abnormal condition which could be tied to recent weather events leading to increased runoff or snowmelt. The lower water levels observed in several lakes, although not far from their average measurements, might implicate reduced snowpack levels or below-average river inflows. As the data lacks detailed information on weather conditions or snowpack data, further analysis and cross-referencing with meteorological and hydrological records would be necessary to pinpoint the exact causes of these irregularities. Nonetheless, it is essential for local authorities and residents to monitor these trends, as they can impact water availability, recreational activities, and ecological health of the water bodies in question.

Iowa has several major reservoirs, including Coralville Lake, Rathbun Lake, and Saylorville Lake. These reservoirs are primarily fed by the Iowa River, Des Moines River, and Chariton River, respectively. Snowpack and mountains are not significant factors in Iowa's hydrology. Coralville Lake has experienced record high water levels in the past, with flooding in 2008 and 2013 causing significant damage. Drought conditions have also affected Iowa's reservoirs, with Saylorville Lake reaching record low levels in 2012. Seasonal trends in Iowa typically involve greater precipitation in the spring and summer months, leading to higher reservoir levels. However, prolonged periods of drought can disrupt this pattern. Overall, reservoirs and dams serve an important role in managing Iowa's water resources and mitigating the risk of floods and droughts.

Iowa has several major reservoirs, including Coralville Lake, Rathbun Lake, and Saylorville Lake. These reservoirs are primarily fed by the Iowa River, Des Moines River, and Chariton River, respectively. Snowpack and mountains are not significant factors in Iowa's hydrology. Coralville Lake has experienced record high water levels in the past, with flooding in 2008 and 2013 causing significant damage. Drought conditions have also affected Iowa's reservoirs, with Saylorville Lake reaching record low levels in 2012. Seasonal trends in Iowa typically involve greater precipitation in the spring and summer months, leading to higher reservoir levels. However, prolonged periods of drought can disrupt this pattern. Overall, reservoirs and dams serve an important role in managing Iowa's water resources and mitigating the risk of floods and droughts.