thumbnail

Development of a Two-Dimensional Hydraulic Model for the Kalamazoo River Between the Trowbridge and Allegan City Dams, Michigan

Scientific Investigations Report 2026-5026
Prepared in cooperation with the U.S. Environmental Protection Agency Great Lakes Restoration Initiative; the Michigan Department of Natural Resources; and the Michigan Department of Environment, Great Lakes, and Energy
By: , , , , and 
https://doi.org/10.3133/sir20265026

Links

Abstract

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 (ft3/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 ft3/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.

Plain Language Summary

The U.S. Geological Survey built a detailed computer model of how water moves through a 9.2-mile stretch of the Kalamazoo River between the Trowbridge and Allegan City Dams to support dam removal and river restoration planning. Model results were checked against field measurements of water levels and flow speeds, and the model matched water levels very closely (generally within a few inches). Flow speeds were slightly underpredicted, by an average of 0.28 foot per second. For a streamflow scenario of 4,000 cubic feet per second (a flow size expected in about half of all years), the model showed that in the first 3.4 miles below Trowbridge Dam, average flow speeds are often 3–4 feet per second and sometimes greater than 4 feet per second. Farther downstream, average speeds rarely exceed 3 feet per second. From the simulated bed shear stresses, the smallest riverbed material likely to stay in place at this flow is mostly pebbles (4–64 millimeters) in the main channel. Finer sands and silts are expected to remain stable in floodplain and backwater areas, where currents are slower. The model gives a high-resolution picture of water levels, currents, and sediment stability in places and at streamflow conditions that are hard to measure in the field. Those insights help decision makers understand habitat connectivity and bed stability as they plan dam removal and river restoration actions.

Suggested Citation

Roland, C.J., Vaughan, A.A., Fitzpatrick, F.A., Broerman, H.M., and Lund, J.W., 2026, Development of a two-dimensional hydraulic model for the Kalamazoo River between the Trowbridge and Allegan City Dams, Michigan: U.S. Geological Survey Scientific Investigations Report 2026–5026, 54 p., https://doi.org/10.3133/sir20265026.

ISSN: 2328-0328 (online)

Study Area

Table of Contents

  • Acknowledgments
  • Abstract
  • Plain Language Summary
  • Introduction
  • Field Data Collection
  • Development of a Two-Dimensional Hydraulic Model 
  • Hydraulic Simulation Results
  • Summary and Conclusions
  • References Cited
  • Appendix 1. Quasi-Steady Streamflow Scenario Velocity Maps
  • Appendix 2. Quasi-Steady Streamflow Scenario Depth Maps
  • Appendix 3. Quasi-Steady Streamflow Scenario Basal Shear Stress Maps
  • Appendix 4. Quasi-Steady Streamflow Scenario Minimum Stable Grain Size Maps
Publication type Report
Publication Subtype USGS Numbered Series
Title Development of a two-dimensional hydraulic model for the Kalamazoo River between the Trowbridge and Allegan City Dams, Michigan
Series title Scientific Investigations Report
Series number 2026-5026
DOI 10.3133/sir20265026
Publication Date June 18, 2026
Year Published 2026
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Upper Midwest Water Science Center
Description Report: vii, 54 p.; 2 Data Releases; Dataset
Country United States
State Michigan
Other Geospatial Allegan City Dam, Kalamazoo River, Trowbridge Dam
Online Only (Y/N) Y
Additional Online Files (Y/N) N
Additional publication details