+42.97227, -85.06930
42°58'20" N, 85°04'09" W


Source: National Bridge Inventory. Information not verified; use at your own risk.
Name:M-66 over GRAND RIVER
Structure number:000000000003970
Old structure number:34134032000B010 (from 1992 edition)
Location:IN IONIA
Purpose:Carries highway and pedestrian walkway over waterway
Route classification:Minor Arterial (Urban) [16]
Length of largest span:75.1 ft. [22.9 m]
Total length:375.0 ft. [114.3 m]
Roadway width between curbs:45.9 ft. [14.0 m]
Deck width edge-to-edge:59.7 ft. [18.2 m]
Owner:State Highway Agency [01]
Year built:1948
Historic significance:Bridge is not eligible for the National Register of Historic Places [5]
Design load:MS 18 / HS 20 [5]
Number of main spans:5
Main spans material:Steel [3]
Main spans design:Stringer/Multi-beam or girder [02]
Deck type:Concrete Cast-in-Place [1]
Wearing surface:Latex Concrete or similar additive [3]

Latest Available Inspection: February 2018

Good/Fair/Poor Condition:Fair
Status:Open, no restriction [A]
Average daily traffic:17,638 [as of 2015]
Truck traffic:3% of total traffic
Deck condition:Good [7 out of 9]
Superstructure condition:Satisfactory [6 out of 9]
Substructure condition:Good [7 out of 9]
Structural appraisal:Equal to present minimum criteria [6]
Deck geometry appraisal:Basically intolerable requiring high priority of replacement [2]
Water adequacy appraisal:Equal to present desirable criteria [8]
Roadway alignment appraisal:Equal to present desirable criteria [8]
Channel protection:Bank is beginning to slump. River control devices and embankment protection have widespread minor damage. There is minor stream bed movement evident. Debris is restricting the channel slightly. [6]
Scour condition:Bridge is scour critical; bridge foundations determined to be unstable. [3]
Sufficiency rating:75.7

Previous Inspections

DateConditionDeckSuperstructureSubstructureADTSuff. Rating
February 2018FairGoodSatisfactoryGood1763875.7
September 2016PoorGoodFairPoor1766245.0
September 2014FairGoodSatisfactoryFair1766263.6
October 2012FairGoodSatisfactoryFair1766263.6
October 2010FairGoodSatisfactoryFair1766263.6
October 2008FairSatisfactorySatisfactoryFair1766262.6
October 2006FairSatisfactorySatisfactoryFair1739262.7
November 2004FairSatisfactorySatisfactoryFair1500061.6
January 2003FairSatisfactorySatisfactorySatisfactory1500073.5
February 2001FairSatisfactorySatisfactorySatisfactory1500073.5
November 1999FairSatisfactorySatisfactorySatisfactory1500073.5
May 1998PoorFairPoorSatisfactory1500045.1
June 1997PoorFairPoorSatisfactory1500045.1
May 1996Poor-PoorSatisfactory1500046.3
August 1995PoorSatisfactoryPoorSatisfactory1780045.3
December 1993PoorSatisfactoryPoorSatisfactory1780045.3
June 1992PoorSatisfactoryPoorSatisfactory1780045.3
May 1991PoorSatisfactoryPoorSatisfactory1780045.3