• Massive Wall Beams make their move to Chickamauga Lock

    After over a decade in storage, massive 120-foot-long concrete wall beams are being transported by barge from Watts Bar Dam to the Chickamauga Lock Replacement Project site, marking a key milestone in improving navigation infrastructure on the Tennessee River. These beams, originally fabricated in 2013, are crucial to completing the upstream approach wall, which is now 68% finished. The transport involves careful coordination using hydraulic systems and rotating barges over several weeks, with beam installation underway. Once complete, the new lock will significantly increase efficiency for commercial navigation, processing nine jumbo barges per lockage compared to just one currently.
  • Army Corps seeks public comment on Fire Island to Montauk Point coastal storm risk management nonstructural pilot program

    The U.S. Army Corps of Engineers announced today it is seeking comments on the Draft Supplemental Environmental Assessment for the Fire Island to Montauk Point, New York, coastal storm risk management nonstructural pilot program.
  • Morphology Control in Waterborne Polyurethane Dispersion Nanocomposites Through Tailored Structure, Formulation, and Processing

    Abstract: Waterborne polyurethane dispersions (PUDs) have garnered increasing interest in recent years due to the growing demand for environmentally friendly materials. The unique phase-separated morphologies exhibited in PUD films and coatings provide opportunities for directing the distribution of functional additives and controlling properties. Although there has been extensive research on polyurethanes for several decades, the mechanisms underlying the PUD morphology formation are poorly understood. The morphologies are driven by interactions between hard segments (HS), and the process is further complicated by the presence of colloidal particles and the intricate interaction between the urethane/urea linkages and water. In this work, structure−property-processing relationships between HS content and structure, relative humidity, particle size, and the resulting dry film morphology of PUDs were determined in two diisocyanate systems: hexamethylene diisocyanate (HDI), a symmetric, flexible diisocyanate; and isophorone diisocyanate (IPDI), an asymmetric, sterically hindered cyclic diisocyanate. HDI-based films exhibited semicrystalline morphologies with HS superstructures that are sensitive to relative humidity. IPDI-based films displayed spherical coalescence-suppressed morphologies influenced by particle size and zeta potential. PUD compositions and processing conditions were controlled to produce nanocomposite films with an enhanced dispersion of nanoadditives.
  • Airborne Bacteria over Thawing Permafrost Landscapes in the Arctic

    Abstract: Rapid warming in the Arctic, outpacing global rates, is driving significant changes in cryospheric landscapes, including the release of long-preserved microorganisms. This study focuses on thawing permafrost in Northern Alaska, where microbes previously preserved in frozen soils are introduced into thermokarst lakes, rivers, and coastal waters and may also become airborne as bioaerosols. We present the first microbial composition measurements of bioaerosols in Alaska, identifying their local sources, such as soils, water bodies, and vegetation. Although sea/brackish water is the dominant bioaerosol contributor, we provide the first evidence of permafrost microbial signatures in bioaerosols from permafrost-laden regions. Permafrost is highly enriched with ice nucleating particles (INPs), which play a crucial role in cloud formation, precipitation processes, and radiation budget despite their relatively low atmospheric concentrations. With rising Arctic temperatures, increased permafrost thaw could result in higher levels of airborne permafrost-derived microbes and biological INPs active at warmer subzero temperatures. This, in turn, could enhance precipitation, further accelerating the permafrost thaw. Our findings emphasize the complex interactions between terrestrial changes and atmospheric processes, revealing a potential feedback loop that could intensify permafrost thaw and its broader environmental impacts.
  • ROTC Cadet Brandon Dove completes USACE internship

    Cadet Brandon Dove is one of 14 Army Reserve Officers’ Training Corps (ROTC) cadets from universities nationwide who spent the summer interning with the U.S. Army Corps of Engineers, Savannah District.
  • Road Closure over Red Rock Dam September 8-10

    The U.S. Army Corps of Engineers, Rock Island District, announces a full road closure to Highway T15 across the Red Rock Dam September 8-10. The closure is necessary for the ongoing rehabilitation project on the Red Rock Dam gates. Additional partial and full road closures may be needed throughout 2025. For more information, contact the U.S. Army Corps of Engineers at Lake Red Rock at 641-828-7522 or by email at: lakeredrock@usace.army.mil.
  • USACE accepts applications to burn flood debris around Beaver Lake

    The U.S. Army Corps of Engineers Beaver Lake Project Office is accepting applications from adjacent landowners to burn driftwood and other flood debris on public land around Beaver Lake through Aug. 15, 2026.
  • Single lane closure scheduled for Highway 177 across Norfork Dam

    The U.S. Army Corps of Engineers will be closing one lane of the Highway 177 bridge across Norfork Dam beginning at 6 a.m. Sept. 9 through Oct. 30, 2025, to perform routine maintenance. The lane closure will remain in place 24 hours a day until the work is complete.
  • Coastal Hazards System–Gulf of Mexico (CHS-GoM)

    Abstract: The US Army Corps of Engineers completed the South Atlantic Coastal Study (SACS) to quantify storm surge and wave hazards, expanding the Coastal Hazards System (CHS) to the South Atlantic Division (SAD) domain. The goal of CHS-SACS was to quantify coastal storm hazards for present conditions and future mean sea level fluctuation scenarios to reduce flooding risk and increase resiliency in coastal environments. CHS-SACS was completed for three regions within the SAD domain, and this report focuses on the Gulf of Mexico (CHS-GoM). This study applied the CHS’ Probabilistic Framework with Joint Probability Method Augmented by Metamodeling Prediction (JPM-AMP) to perform a probabilistic coastal hazard analysis (PCHA) of tropical cyclone (TC) and extratropical cyclone (XC) responses, including new atmospheric and hydrodynamic numerical model simulations of synthetic TCs and historical XCs. This report documents the CHS probabilistic framework for the CHS-GoM region by executing the JPM-AMP, and comprising storm climate characterization, storm sampling, storm recurrence rate estimation, marginal distributions, correlation and dependence structures of TC atmospheric-forcing parameters, development of augmented storm suites, and assignment of discrete storm weights to the synthetic TCs. Coastal hazards were quantified for annual exceedance frequencies over the range of 10 yr−1 to 10−4 yr−1.
  • Army Corps shares update on Francis E. Walter Dam water release schedule

    The U.S. Army Corps Engineers’ Philadelphia District updated the 2025 Francis E. Walter Dam recreation plan. The Army Corps updated the plan, which states whitewater and fisheries releases will be scheduled if enough water storage is accumulated in the reservoir. Currently, there is enough water storage to schedule the 12th increment of the plan, which includes adding fishing releases for the period of September 13-26.