Geology topics

Collin J. Roland

Publications and source records attributed to Collin J. Roland.

4 recordsLinked to original sources

USGS2026

Development of a two-dimensional hydraulic model for the Kalamazoo River between the Trowbridge and Allegan City Dams, Michigan

The U.S. Geological Survey developed a two-dimensional hydraulic model for a 9.2-mile reach of the Kalamazoo River between the Trowbridge and Allegan City Dams. The model simulates streamflow conditions with spatial coverage and resolution that would be difficult or dangerous to document with field measurements, enabling assessments of habitat connectivity and substrate stability to support dam removal and restoration planning. The model was calibrated with surveyed water surface elevation (WSE) profiles, streamgage WSE time series, and measured depth-average velocities. Modeled WSE profiles had root mean square error (RMSE) values of 0.20 and 0.32 foot. Cross-sectional average velocities were slightly underpredicted, with RMSE of 0.28 and 0.30 foot per second (ft/s). Channel roughness varied with stage, and the high-flow model reproduced streamgage WSE time series with an RMSE of 0.04 foot. Quasi-steady simulations at 4,000 cubic feet per second (ft 3 /s), about the 50-percent annual exceedance probability streamflow, indicated that cross-sectional average velocities within 3.4 miles downstream from Trowbridge Dam were commonly between 3 and 4 ft/s, occasionally exceeding 4 ft/s. Farther downstream, velocities seldom exceeded 3 ft/s. Simulated shear stresses were used to estimate substrate stability in the reach. At 4,000 ft 3 /s, the minimum stable grain size along most of the main channel was predicted to be in the pebble range (4–64 millimeters), and sands and silts were predicted to be stable in the floodplain and backwaters.

Michigan↗

USGS2026

FluOil—A tool for estimating the transport and deposition of oil-particle aggregates in rivers

The FluOil tool was developed to help with planning and early response for oil spills in rivers where subsurface oil-sediment interactions result in the formation of oil-particle aggregates (OPA). The turbulence and variable velocity associated with water flowing within a natural stream channel creates the conditions needed for an oil slick to break up into small droplets and mix in the water column, collide with sediment or organic detritus, and form OPA. This process is similar to what occurs due to wave action along a shoreline. The FluOil tool estimates how fast OPA travel downstream in rivers as well as when and where they may deposit. The FluOil tool relies on pre-existing channel hydraulic data along with user-specified OPA characteristics of size, settling velocity and critical shear stress to compute OPA transport. It is important to know where OPA are transported and accumulated for understanding potential impacts on drinking water intakes, burial of sensitive habitat beds, potential toxicity to benthic organisms, and prolonged sheening from resuspension and breakup. OPA tend to accumulate with fine-grained (silt and clay) sediment deposits (“mud” or “muck”) in backwater areas, oxbows, side channels, pools, and other slow-moving reaches of rivers during low flows. Deposited OPA can be resuspended during high flows, driving continued environmental impact concerns that may extend beyond typical oil spill response timelines.

Fact Sheet↗

USGS2025

Beach nourishment response and recent morphological evolution of Minnesota Point, Lake Superior

Beach nourishments are a popular nature-based alternative to armoring for shoreline erosion mitigation, but nourishments have been criticized due to their environmental impacts and uncertain sustainability. Monitoring is often nonexistent or insufficient to constrain nourishment longevity and inform the renourishment interval required to maintain shoreline protection. This study uses a combination of topobathymetric surveys, high-resolution satellite-derived shorelines, and coastal engineering analyses to investigate the recent evolution of Minnesota Point and the fate of three beach nourishments constructed adjacent to littoral barriers. We use semi-empirical formulations for sediment compatibility, wave runup, and longshore sediment transport to inform the observed nourishment behavior. Minnesota Point experienced widespread foredune retreat averaging 7±2.8 m from 2009–2019 and 130,000 (70,000–140,000) m 3 of sediment was eroded during this interval. The 2019 nourishment at the Superior Entry was rapidly eroded by strong storms, losing >80% of the added beach width by the following spring. The 2020 and 2021 nourishments at the Duluth Entry retained >80% of the nourishment material at the time of the last topobathymetric survey in the fall of 2022, and satellite-derived shorelines indicate that the beach remained 10 m wider than pre-nourishment conditions at the end of 2023. Modeled longshore transport rates over the period 2009–2022 averaged 11,400 m 3 yr −1 northwestward at the Superior Entry, nearly 3x greater than the 4000 m 3 yr −1 southeastward transport modeled at the Duluth Entry. These observations show that differences in shoreline orientation, littoral sediment supply, and grain size compatibility can lead to contrasting beach nourishment longevities, and this study provides additional measurements of Minnesota Point’s long-term morphological change which can help inform coastal resiliency efforts.

Minnesota, Wisconsin↗

USGS2025

Effects of river floods and sedimentation on a naturally dynamic Great Lakes estuary

Some of the most biologically diverse coastal wetlands and estuaries are found along the Great Lakes, but the spatial extent and timing of river-related inundation and sedimentation vary greatly among natural and altered systems. We used hydrologic data, geomorphic change detection, and satellite imagery to study inundation and sedimentation patterns in the naturally dynamic estuary of the Bad River ( Mashkiiziibii ) that flows into Lake Superior ( Anishinaabeg-gichigami ), and the Kakagon River ( Ogaakaagaang-ziibii ) that flows into a sheltered bay ( Chi-Kaamigong ). In 2016, an extreme summer flood (annual exceedance probability < 0.2 %) caused total inundation of the 46-km 2 estuary. Floods from the sediment-rich Bad River, with an annual exceedance probability of ≤ 50 %, have overflowed into the upper wetlands and channels of the Kakagon River about 60 times over the last 75 years, including 20 floods during the most recent 10-year wet period. Sedimentation patterns were associated with proximity to river channels, shoreline erosion, and wind action. Early winter ice-up coupled with a storm surge and an early spring snowmelt into the iced-over bay changed inundation duration and sedimentation patterns. Climate-change projections for more intense rainfall and warmer temperatures will likely cause more frequent flooding and sedimentation; however, patterns may differ depending on the timing of the floods relative to storm surges and ice formation, or other factors. The approach of integrating readily available data helped give a broader temporal and spatial context to the possible causes for inundation and sedimentation, some expected and others not, in natural and restored estuaries of the Great Lakes.

Wisconsin↗