Rating:
6 votes

Sylvan Island Bridge

Photos 

Photo taken by Dave Sebben

View this photo on Flickr

BH Photo #200159

Map 

Street View 

Facts 

Overview
Pratt through truss bridge over Sylvan Slough on 2nd Street
Location
Moline, Rock Island County, Illinois
Status
Intact but closed to all traffic
History
Built 1901; Bearing plate repaired 1945, Timber deck replaced by concrete 1953; Floor system repaired 1964; Closed 1969; Converted to pedestrian usage in 1995; Closed 2013, Demolished 2017
Design
1 89' six panel pin-connected Pratt truss
1 110' seven panel pin-connected Pratt truss.
Dimensions
Length of largest span: 110.0 ft.
Total length: 200.0 ft.
Also called
Sylvan Island Wagon Bridge
2nd Street Sylvan Island Bridge
Approximate latitude, longitude
+41.51097, -90.53599   (decimal degrees)
41°30'39" N, 90°32'10" W   (degrees°minutes'seconds")
Approximate UTM coordinates
15/705625/4598413 (zone/easting/northing)
Quadrangle map:
Davenport East
Inventory number
BH 48242 (Bridgehunter.com ID)

Update Log 

  • November 25, 2017: Updated by John Marvig: Bridge has Been Replaced
  • September 12, 2013: New Street View added by Dave King
  • April 30, 2013: Updated by John Marvig: Bridge is now closed
  • December 29, 2012: New photos from John Marvig
  • December 28, 2012: Updated by John Marvig: Added information
  • June 4, 2011: Updated by Luke Harden: Added photograph
  • February 24, 2011: Added by Nathan Holth

Sources 

Comments 

Sylvan Island Bridge
Posted November 26, 2017, by Jason Smith (flensburg [dot] bridgehunter [dot] av [at] googlemail [dot] com)

Replacement in place, scheduled to open in December. Man, that is one very ugly MOB! No historic value!!! http://qctimes.com/lifestyles/recreation/long-awaited-bridge...

Sylvan Island Bridge
Posted October 9, 2014, by ArtS (asuckewer [at] knite [dot] com)
Sylvan Island Bridge
Posted April 14, 2014, by Nathan Holth (form3 [at] historicbridges [dot] org)

This confirms what the newspapers said... a quote from the report: "The entire superstructure vibrates under the loading of two men walking. A single man jumping up and down on the deck creates noticeable vibrations throughout the truss."

This is true for any pin-connected truss! Its how they function! This is not a rigid-connected truss bridge... it is pin connected!

Sylvan Island Bridge
Posted April 12, 2014, by Anon (none [at] none [dot] com)

If you want to read the bridge inspection report it can be found here (lots of good photos at the end): http://www.moline.il.us/DocumentCenter/View/2047

Major section loss in a few of the lower truss chord members seems to be the main reason for closing the bridge. A few other serious problems were found with the deck support beams, deck, and some of the joints.

2nd Street Sylvan Island Bridge
Posted September 12, 2013, by John Marvig (johnmarvig [at] chaska [dot] net)

They sure as hell better bring in that railroad span then!

2nd Street Sylvan Island Bridge
Posted September 11, 2013, by Jason Smith (JDSmith77 [at] gmx [dot] net)

That's just dumb! Where the hell did they get the figures from anyway? I think there should be a better way to preserve the bridge rather than demolish it. But I guess the politicians just don't get it, do they?

2nd Street Sylvan Island Bridge
Posted September 11, 2013, by Nathan Holth (form3 [at] historicbridges [dot] org)

I don't know who they hired, but Moline obviously hired someone with no experience whatsoever in rehabilitation of historic truss bridges since they now think its cheaper to demolish and replace this bridge rather than preserve it.

http://www.whbf.com/story/23304831/future-bright-for-sylvan-...

2nd Street Sylvan Island Bridge
Posted August 13, 2013, by Anonymous

Phoenix column Whipple railroad truss. Walleye tournament in October 2012.

2nd Street Sylvan Island Bridge
Posted April 30, 2013, by B. Lauver (bllauver [at] toad [dot] net)

Is there any longer public access to Sylvan Island? The road bridge is closed and the RR bridge appears to be shut off from trails.

2nd Street Sylvan Island Bridge
Posted April 30, 2013, by Nathan Holth

"Too much bounce?" Seriously? Whoever inspected this bridge does realize this is a PIN CONNECTED truss bridge, right? Obviously, these bridges do flex noticeably under load. Does this person not know this? The only situation where "bounce" would be of concern is if an underlying issue caused excess flex, and if so, it is the underlying issues that should be described, such as section loss, sinking abutments, etc.

2nd Street Sylvan Island Bridge
Posted April 30, 2013, by John Marvig (johnmarvig [at] chaska [dot] net)

http://qctimes.com/news/local/fencing-goes-up-to-block-sylvan-island-bridge-in-moline/article_9beff152-61e5-5b9a-a30b-db2fa7a0e401.html?comment_form=true

Closed....

2nd Street Sylvan Island Bridge
Posted February 24, 2011, by Nathan Holth (form3 [at] historicbridges [dot] org)

OK, I think I have the two Sylvan Island Bridges represented correctly on this website. This is the highway bridge. Some websites say this bridge was built in 1872 by Baltimore Bridge Company, and "strengthened in 1901". However, the truss spans do not look even remotely like something built in 1872. I strongly believe that the bridge was replaced in 1901 with the spans seen today. The former substructure from 1872 may have been reused, which may be why there is this confusion. Given these observations, I listed the construction date as 1901 and the builder as unknown.

Note that the other bridge to this island is a nationally significant (but little known) Phoenix column Whipple railroad truss.