Joe Rathbun Michigan DEQ Water Resources Division Nonpoint Source Unit rathbunj@mi.gov * Thanks to The Nature Conservancy
Road-stream intersections = 67,511 Culverts = 60,700 Bridges = 6,811
Perched Piping Blockage Sediment
Michigan Department of Natural Resources and Michigan Department of Environmental Quality 2007 Culvert Application Inventory 2007 > Stream Width 40% 48% < Stream Width 12% = Stream Width Culvert applications reviewed 240
Buried 27% Michigan Department of Natural Resources and Michigan Department of Environmental Quality 2007 Culvert Application Inventory 2007 73% Not Buried Culvert applications reviewed 224
Culverts and Fish Passage Increased passage with: Increased width (at least bankfull width) Decreased slope Decreased length Decreased perching (< 0.7 ft) Moderate water velocities (< 3 ft/sec?) Strong link between restricted fish, water & sediment movement
Installation Guideline = MESBOAC Match culvert width to bankfull width** Extend culvert length through side slope toe Slope of culvert = channel slope** Bury culvert 1/6 th bankfull width Offset multiple culverts Align culvert with stream Consider headcuts **Biggest limitations to fish passage & cause of failure (Dr. Sandy Verry, Ellen River Partners)
Bankfull Channel Ordinary High Water Mark Baseflow Channel
Bankfull Elevation Examples First depositional flat Absent from incising streams Look for depositional features
Bankfull Elevation Examples
Avoid width measurements at the road Widening due to aggradation Widening due to scour Measure at the narrowest point on the channel away from the existing crossing - normally at riffles
Match Bankfull Width Too small = high velocities = erosion downstream Osborn Creek Bankfull width = 26 ft Culvert width = ~ 6 ft Downstream = plunge pool, perched, bank erosion
Large culverts = install bankfull benches Constructing a Lowflow Chann
ELEVATION-FT Match the Channel Slope 1003 1002 1001 1000 999 998 997 Bankfull elevation 996 995 Slope = 0.0191 Water Surface elevation 994 Thalweg elevation 993 0 50 100 150 200 250 300 350 400 THALWEG DISTANCE-FT Channel slope = u/s riffle crest to d/s riffle crest
Case Study: Bruno Creek, Houghton County Logging road crossing = soil erosion from crossing & collapsed culvert
Bruno Creek, Houghton County Replacement bridge spans channel width Channel narrower, deeper, rockier
Bruno Creek, Houghton County Habitat improved substantially Metric 1991 2001 Bottom substrate 2 11 Embeddedness 3 9 Velocity:depth 8 15 Bottom deposition 3 8 Habitat heterogeneity 4 9 Bank stability 4 7 Bank vegetative stability 5 10 Overall score 46 (Poor) 90 (Good)
Bruno Creek, Houghton County Metric 1991 (before) 2001 (after) Total # of EPT families 4 9 % mayflies 9 14 % caddisflies 4 20 % isopods, snails, & leeches Macroinvertebrates also improved; sensitive bugs increased, tolerant bugs decreased 6 1 % air-breathing taxa 10 0
Case Study: Hull Creek, Manistee Co. Post Pre Stephanie Ogren Little River Band Ottawa Indians
Case Study: Hull Creek Fish or Metric Pre Fish/minute Post Fish/minute Slimy sculpin 4.9 2.1 Coho salmon 0 1.4 Brown trout 0 0.4 Fish IBI 86.5 98.0 Stephanie Ogren Little River Band Ottawa Indians
Other wildlife, too
Wildlife too Western mud turtle
Crossings and Climate Change Higher Spring, Winter & Fall precipitation = increased risk of floods & washouts Climate-proof roads Union of Concerned Scientists, 2009
Crossings and Climate Change Michigan s climate is moving south Higher summer temps & lower precipitation = decreased coldwater fish habitat Union of Concerned Scientists, 2009
Crossings and Climate Change Higher summer temps & lower precipitation = decreased coldwater fish habitat MDNR
Replacement Costs Stream-friendly culvert can be 10% to 100% more expensive than traditional culvert Depends mostly on original culvert size But, less frequent maintenance and replacement Average annual cost lower over lifetime (30-70 years) Advantages will increase with climate change Emergency culvert replacement costs = 4 to 140 times normal replacement costs due mostly to delay costs
Case Study: Lewis Brook, NY Life spans: pipe culverts = 30 years, box culvert = 75 years Annual costs over 70 years (culvert only) Pipe culverts = $2,726 Box culvert = $2,900 6% difference TNC, 2013
Climate Change Hypothetical Cost Scenario Small pipe culvert vs. larger box culvert Storm frequency that causes pipe culvert failure # years for annual cost of box culvert to become less than pipe culvert Once per 30 years 90 Once per 25 years 69 Once per 20 years 40 Once per 15 years 30 Once per 10 years 21 Once per 5 years 10 TNC, 2013
Permit Categories General Permit & Minor Project Permit (GP & MP) Projects with minimal or minor impacts Lower fees, shorter review times GP & MP utilize MESBOAC concepts Size = 1.2 times bankfull width Slope flat or matches stream Bottomless or buried Aligned with centerline of stream Contact Bethany Matousek matousekb@mi.gov
Upcoming training MDEQ = bankfull training; contact Bethany Matousek matousekb@mi.gov =================== US Forest Service = aquatic organism passage May 2015 Cadillac contact Dan Cenderelli dcenderelli@fs.fed.us