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Hydrologic Analysis for NPS 319 and CMI Grants. Hydrologic Analysis for NPS 319 and CMI Grants. Dave Fongers, HSU, MDEQ, 517-373-0210, fongersd@michigan.gov. Definitions. Hydrology: the occurrence, distribution, and movement of water both on and under the earth's surface.
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Hydrologic Analysis for NPS 319 and CMI Grants Hydrologic Analysis for NPS 319 and CMI Grants Dave Fongers, HSU, MDEQ, 517-373-0210, fongersd@michigan.gov
Definitions Hydrology: the occurrence, distribution, and movement of water both on and under the earth's surface. Stream Morphology: the form and structure of a stream (sinuosity, profile, and cross-sectional dimensions). Morphologic Stability: no net change in channel shape, which occurs only if the channel-forming flow is also stable. A stable stream will have natural erosion. Hydrologic changes can cause a stream to be unstable for 60 years or more.
Channel-Forming Flow is the flood discharge that causes the channel to assume its existing shape. Extreme flood flows generally have little effect on channel morphology because they are so rare. More frequent flows, those that recur about every1.5 to 2-years, are generally the dominant channel-forming flows in stable, natural streams (Schueler, 1987 and Rosgen, 1996).
Water can carry 64 times larger particles if the velocity is doubled. Increase Flow or Slope Increase Sediment, Erosion
Hager Creek Instability is indicated by extensive, excessive erosion, especially along straight reaches.
Hager Creek Down-cuts are good indicators of instability.
Hager Creek A more typical down-cut.
Goals of NPS Hydrologic Analysis • Help identify the cause(s) of streambank erosion • Facilitate the selection and design of suitable stabilization BMPs • Understand and plan for future hydrologic change • Help define critical areas for the Watershed Management Plan
Goals of NPS Hydrologic Analysis • Help identify the cause(s) of streambank erosion • Facilitate the selection and design of suitable stabilization BMPs • Understand and plan for future hydrologic change • Help define critical areas for the Watershed Management Plan
A. ID erosion causes Blakeslee Creek Land Use Change
A. ID erosion causes Blakeslee Creek 70% increase in peak flow, 170% increase in runoff volume, former instantaneous peak flow now lasts ~4 hours Pre-development Post-development Predicted 50 percent chance (2-year) flow from calibrated model.
Blakeslee Creek Instability is indicated by extensive, excessive erosion, especially along straight reaches.
A. ID erosion causes Gage Analysis Gage Analysis 4712 cfs 67% (1.5-year), 6368 cfs 50% (2-year), 10397 cfs 10% (10-year)
A. ID erosion causes Gage Analysis
A. ID erosion causes Pine River Livestock Cause Cause Cause Cause Cause Cause Cause Sometimes the cause of the erosion is obvious.
A. ID erosion causes Foot Traffic
A. ID erosion causes FlowObstructions Bear Creek This erosion may be caused by flow diverting around debris or ice piling against the former bridge supports. Nearby streambanks are stable.
A. ID erosion causes Natural Erosion
Goals of NPS Hydrologic Analysis • Help identify the cause(s) of streambank erosion • Facilitate the selection and design of suitable stabilization BMPs • Understand and plan for future hydrologic change • Help define critical areas for the Watershed Management Plan
B. BMP design Fleming’s/River Rouge This CMI-funded detention pond’s drainage area is nearly fully developed. Based on the grantee’s hydrologic analysis, the 2-year event release rate is 0.018 cfs/acre.
A. ID erosion causes East Branch AuGres River This erosion started 80 years ago when fourteen miles of natural stream was diverted to a three-mile long, straight channel. The hydrologic study provided design flows.
B. BMP design Hager Creek Hydrologic analysis provided design flows. Hydraulic analysis verified the effect of the proposed channel changes.
Goals of NPS Hydrologic Analysis • Help identify the cause(s) of streambank erosion • Facilitate the selection and design of suitable stabilization BMPs • Understand and plan for future hydrologic change • Help define critical areas for the Watershed Management Plan
C. Plan for future changes Black River
C. Plan for future changes Black River, 4% storm
C. Plan for future changes Sand Creek
C. Plan for future changes Sand Creek
C. Plan for future changes Sand Creek
C. Plan for future changes Sand Creek
C. Plan for future changes Sand Creek
C. Plan for future changes 0.13 0.05
C. Plan for future changes From Gun River Hydrologic and Hydraulic Study, Appendix 6
C. Plan for future changes From Gun River Hydrologic and Hydraulic Study, Appendix 6
Goals of NPS Hydrologic Analysis • Help identify the cause(s) of streambank erosion • Facilitate the selection and design of suitable stabilization BMPs • Understand and plan for future hydrologic change • Help define critical areas for the Watershed Management Plan
D. Define critical areas Excerpt from Coldwater River Watershed Management Plan, Tables 13 & 14