23 Oct 2020

Corps updates stakeholders on Missouri River Mainstem System operations

The US Army Corps of Engineers Missouri River Water Management Division hosted an update call on Thursday, Oct. 22, for Congressional representatives, Tribal, and state and local government officials, to include emergency managers, local levee sponsors and the media to discuss current conditions, and the projected operation of the mainstem reservoir system as part of the Draft Annual Operating Plan which was released in mid-September for public comment.

14 Oct 2020

The Demonstration and Validation of a Linked Watershed-Riverine Modeling System for DoD Installations – Patuxent Watershed, Maryland

Abstract: This work evaluated a linked watershed and riverine modeling system for the Patuxent River Watershed, Maryland against observed field data and model output from a watershed model. The performance objectives were computed for streamflow, sediment, total phosphorus, orthophosphorus, total nitrogen, ammonium, and nitrate using daily and monthly average model predictions and measured data. Hydrological Simulation Program – Fortran (HSPF) was used to compute runoff, sediment, and nutrient loadings, whereas the Hydrologic Engineer Center – River Analysis Sys-tem (HEC-RAS) was used to evaluate in-stream flow, channel sedimentation, and the fate/transport of nutrients. Model results were successful for calibration, validation, and management scenario analysis. Contaminants were not simulated for this watershed due to a lack of observed data to compare against. The study identified two implementation issues. First, while the Patuxent River did not experience dry bed conditions, where a stream may be intermittent, one can incorporate a very narrow slot at the low point in the cross-section to numerically keep the channel wet during very low flows. Second, to set up the linked model, there needs to be more observed water quality data to better constrain the HSPF output being used as boundary conditions to the HEC-RAS model.

5 Oct 2020

Below average runoff continues in the upper Missouri River basin

September precipitation was well-below normal in the Missouri River Basin.  As a result, September runoff in the upper Missouri River Basin above Sioux City, Iowa was 69% of average.  Since January 1, precipitation in the upper Basin is well-below normal.  The National Weather Service’s Climate Prediction Center (CPC) is forecasting that below-normal precipitation will continue in October.  The 2020 calendar year runoff forecast for the upper Basin, updated on October 1, is 30.2 million acre-feet (MAF), 117% of average. Average annual runoff for the upper Basin is 25.8 MAF.

11 Sep 2020

NR 20-024: Cheatham Lake Right Bank Recreation Area reopens

NASHVILLE, Tenn. (Sept. 11, 2020) – The U.S. Army Corps of Engineers Nashville District announces that the Right Bank Recreation Area Beach at Cheatham Lake in Ashland City, Tennessee, is reopened as water conditions have returned to acceptable levels.