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Tag: water quality
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  • June runoff much below average; Navigation flow support decreased slightly after System storage check

    June runoff in the Missouri River Basin above Sioux City, Iowa was 3.3 million acre-feet, 60% of average. The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average.
  • Estuarine Dams and Weirs: Global Analysis and Synthesis

    Abstract: Estuarine dams and weirs are constructed in estuaries for blocking the salt intrusion, securing freshwater, and stabilizing upstream water levels. While they can provide many social benefits, they also alter physical and sedimentary processes. To address this, we perform and extensive remote sensing and literature analysis. Remote sensing was conducted based on a global river database of 1531 rivers representing the largest rivers cumulatively draining 85 % of the landmass discharging into the global ocean. It was found that 9.7 % of global estuaries and deltas are currently affected by estuarine dams or weirs acting as the upstream limit of salt, tide, or storm surge intrusion. Most estuarine dams and weirs are located at x = 0–100 km inland from the mouth and their discharge intervals can be continuous. They are found most in river mouths which are wave-dominated followed by tide-dominated and then river-dominated. They can cause significant changes to the quantity and timing of freshwater discharge, tides, stratification, turbidity, sedimentation, oxygen conditions, phytoplankton blooms, and fish migration. We propose a conceptual model for physical and geomorphological change in mixed wave- and river-dominated and tide-dominated estuaries with estuarine dams.
  • May runoff average; Missouri River upper basin runoff forecast below normal

    The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. May runoff in the Missouri River Basin above Sioux City was 3.4 million acre-feet, 100% of average.
  • Guidance for Managers of USACE Waterbodies: Deploying the ERDC CyanoSTUN™ for Suppression of Cyanobacterial Harmful Algal Blooms

    Purpose: The purpose of this document is to guide US Army Corps of Engineers (USACE) district personnel in using the US Army Engineer Research and Development Center’s (ERDC) CyanoSTUN™ (Cyanobacterial Suppression Through Ultraviolet-Light-C Neutralization) vessel for suppression of cyanobacterial harmful algal blooms (cyanoHABs). This document describes CyanoSTUN’s capabilities and components, intended operating conditions, and instructions for safe and effective operation of the vessel.
  • Missouri River upper basin runoff forecast lowered due to dry conditions

    The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. April runoff in the Missouri River Basin above Sioux City was 1.4 million acre-feet, 48% of average.
  • Missouri River upper basin runoff continues below average forecast

    The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. March runoff in the Missouri River Basin above Sioux City was 2.3 million acre-feet, 76% of average.
  • Bacterial Remediation of Microsystin-HAB Toxins Utilizing Microcystinase (MlrA)

    Abstract: Microcystins are a class of hepatotoxins produced by some harmful algal bloom–associated cyanobacteria and are the most reported tox-ins in freshwaters. Their cyclic structure makes them resistant to conventional methods used in water treatment operations (boiling, chlorination, and UV treatment). Some bacteria can naturally degrade microcystins via the mlrABCD cluster, a pathway initiated by the primary enzyme microcystinase (MlrA). MlrA linearizes the cyclic microcystin, greatly reducing its toxicity. Protein fusion was employed to produce a recombinant MlrA enzyme fused to maltose-binding protein ([MBP] MBP-MlrA) and to evaluate long-term enzymatic stabilization and reconstitution for future applications. MBP-MlrA degraded cyclic microcystin in vitro and demonstrated stability across a range of biological pHs. At a concentration of 0.61 ng/µl in buffer, MBP-MlrA achieved and maintained an average degradation rate of approximately 101.95 µM/h/ng of protein across fifteen freeze/thaw cycles. Stability assays demonstrated that enzyme activity was preserved over 5 months at −20°C. Results also demonstrated the effectiveness of MBP-MlrA to linearize microcystin upwards of 55.59 µM/h/ng of protein at the bench scale in both buffer and various freshwater matrices. The presence of the linear metabolite is of concern regarding intermediate toxicity, and future studies to incorporate the MlrB peptidase are discussed.
  • Virtual Missouri River water management public meetings set for April

    Two meetings to hear from the public about planned operation of the Missouri River Mainstem System will be held the first week in April.
  • Spring Missouri River public meetings to be virtual

    Virtual meetings on Missouri River Mainstem Reservoir system operations are in the process of being scheduled. Meeting dates and times will be announced as the details are finalized. In-person public meetings on Missouri River Mainstem Reservoir system operations, which were scheduled for March 19, 31 and April 2 have been canceled.
  • Gavins Point releases increasing for navigation flow support; Upper basin runoff stays below average

    The updated 2025 calendar year runoff forecast for the Missouri River Basin above Sioux City, Iowa, continues to be below average. February runoff in the Missouri River Basin above Sioux City was 1.0 million acre-feet, 91% of average. “Runoff into the reservoir system was slightly below average for the month of February and conditions across most of the basin remain dry,” said John Remus, chief of the U.S. Army Corps of Engineers’ Missouri River Basin Water Management Division.