Ninth Street Bridge (Boise, Idaho)

The Ninth Street Bridge in Boise, Idaho, also known as the Eighth Street Bridge, crosses the Boise River and is a 2-span, pin-connected Pratt through truss design constructed by the Missouri Valley Bridge & Iron Co. and completed in 1911. Each span is 160 ft (49 m) and includes six full panels and two end panels, supported by concrete piers at each end and midway in the river. Laced channel sections with cover plates form the upper chords, with eyebars on the lower chords. Eyebars with turnbuckles form the diagonals. The bridge was added to the National Register of Historic Places in 2001.[2]

Ninth Street Bridge
The Ninth Street Bridge in 2019
Ninth Street Bridge (Boise, Idaho) is located in Idaho
Ninth Street Bridge (Boise, Idaho)
Ninth Street Bridge (Boise, Idaho) is located in the United States
Ninth Street Bridge (Boise, Idaho)
LocationE of new 9th Street bridge, over Boise R., Boise, Idaho
Coordinates43°36′34″N 116°12′29″W / 43.60944°N 116.20806°W / 43.60944; -116.20806 (Ninth Street Bridge)
Arealess than one acre
Built1911 (1911)
Built byMissouri Valley Bridge & Iron Co.
ArchitectLapointe & Fox
Architectural stylePratt Through-truss bridge
MPSMetal Truss Highway Bridges of Idaho MPS
NRHP reference No.01000980[1]
Added to NRHPSeptember 14, 2001

History edit

In 1864 the Board of Commissioners of Boise County, Idaho Territory, granted John McLellan and William Thompson a license to operate a ferry across the Boise River at a point on the Oregon Trail near the current location of the Ninth Street Bridge.[3] The McLellan Ferry operated until 1868, when McLellan and Thompson hired flour mill owner H.P. Isaacs to build the Boise City Bridge.[4][5]

In 1911 the old Ninth Street Bridge was moved approximately 12 miles to span the Boise River along the Boise and Interurban Railway line at what is now Linder Road in Meridian, and the Missouri Valley Bridge & Iron Co. built the new Ninth Street Bridge.[6] The Boise Railroad Company secured rights to operate a streetcar across the Ninth Street Bridge in November, 1911,[7] and the bridge became part of the South Boise Loop.[8]

In 1912 a 10-pound box of dynamite was left on a pier under the bridge, but police uncovered no plan for demolition.[9]

The middle pier under the bridge was fortified in 1926 with 600 tons of rock to repair damage caused by the Boise River.[10] In 1928 engineers repaired the center pier again after discovering what the Idaho Statesman termed "vast caverns and yawning spaces" in the center support, when the block of concrete was found to be "hanging from the steel work just like a ring from a Spanish dancer's ear lobe."[11]

By the 1960s, engineers had concluded that the truss bridge should be replaced.[12] In 1987 a new Ninth Street Bridge was constructed directly west of the truss bridge, and the old bridge became a route for pedestrian and bicycle traffic.[2]

See also edit

References edit

  1. ^ "National Register Information System". National Register of Historic Places. National Park Service. November 2, 2013.
  2. ^ a b Donald W. Watts (July 24, 2000). "National Register of Historic Places Inventory/Nomination: Ninth Street Bridge". National Park Service. Retrieved January 10, 2019. With accompanying pictures
  3. ^ "Report of Meeting of Board of Commissioners". Boise News. Idaho City, Idaho Territory. April 2, 1864. p. 1. Retrieved January 11, 2019.
  4. ^ "New Bridge". Idaho Semi-Weekly World. Idaho City, Idaho Territory. January 25, 1868. p. 1.
  5. ^ "McLellan's Ferry" (PDF). Boise Parks & Recreation. Archived from the original (PDF) on August 28, 2018. Retrieved January 11, 2019.
  6. ^ "To Build Two Much Needed Bridges". Idaho Statesman. Boise, Idaho. December 30, 1910. p. 3.
  7. ^ "Legal Notices: In the Matter of Granting Easement to Boise Railroad Company...". Idaho Statesman. Boise, Idaho. November 28, 1911. p. 7.
  8. ^ "South Boise Loop Comes First". Idaho Statesman. Boise, Idaho. November 18, 1911. p. 7.
  9. ^ "Find Dynamite on Bridge". Idaho Statesman. Boise, Idaho. August 10, 1912. p. 3.
  10. ^ "Strengthen Bridge Pier". Idaho Statesman. Boise, Idaho. December 11, 1926. p. 9.
  11. ^ "Concrete Pier Being Repaired". Idaho Statesman. Boise, Idaho. September 21, 1928. p. 6.
  12. ^ "Studies Indicate Bridge Should Be Replaced". Idaho Statesman. Boise, Idaho. January 2, 1968. p. 3.

External links edit

  Media related to Ninth Street Bridge (Boise, Idaho) at Wikimedia Commons