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HAER MICH,41-GRARA,11--2
2. VIEW SOUTH, NORTH ELEVATION - Pearl Street Bridge, Spanning Grand River at Pearl Street, Grand Rapids, MI |
"Significance: The bridge is a good example of open spandrel type arch construction, as described in engineering textbooks published during the first quarter of the twentieth century. This type of bridge construction is labor-intensive, and this design would not be considered cost effective or competitive in today's market place. The bridge setting is prominent and highly visible from adjacent commercial, public and park areas." [
HAER_data]
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| HistoricBridges_pearl |
"The loss of the original railings on these bridge is most unfortunate....The Pearl Street Bridge is the victim of another far more serious alteration: it is actually no longer an arch bridge. Take a close look under the bridge, and you will see that all but the outermost parts of the arch bridge were removed, and modern pre-stressed concrete beams (AASHTO girder style) replaced them. This bridge is essentially a modern bridge with a historic arch facade and historic substructure. As such, the bridge has limited historic value. On the other hand, the bridge still retains its historic appearance and still lends attractive architecture to downtown Grand Rapids. The modifications done to this bridge do not represent a "best practice" for restoration, but do represent a good compromise when the demands for retaining a historic structure compete with a need for an efficient non-weight-restricted crossing. It is an better alternative to outright demolition to be sure! At the same time, arch bridges like this can often be rehabilitated for continued unrestricted use without having to replace the superstructure." [HistoricBridges]
Dam Removal
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Mlive.com posted
Crews installed a floating barrier near Gillett Bridge to contain sediment as the first step in removing four century-old low-head dams along the Grand River in Grand Rapids.
https://mrf.lu/JzNN |
Given the
Blue Bridge in the left background, we are looking South at the Pearl Street Bridge.
This shows that the Pearl Street Bridge on the left is open spandrel, and the Gillet Bridge on the right is closed spandrel. But my main motivation for this view is to confirm that the head for this dam is very low. This is the southernmost dam. Given that the dam upstream of the Gillet Bridge is Dam #2, this must be Dam #1.
Dam #2. Again, it has a very small head. This is the first dam to be removed. After the dam is removed rocks will be placed in the river to create eddies and pools of water to help the fish. The removal and restoration contract was approved for $14.5m. [
mlive]
Dam #3.
Dam #4.
The removal of this dam is still being studied.
Keven Craig Fox 17
posted four photos with the comment: "The heavy lifting has finally begun in the city of Grand Rapids to “Restore the Rapids” on the Grand River. These photos are courtesy of the city, and shows construction equipment and workers in the water starting the project. It’s been in the making for many years, but has now come to fruition. Check it out!"
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