1913-1972 Nolichucky Dam on Nolichucky River south of Greeneville, TN

(Satellite)

An aftermath of Hurricane Helene in Sep 2024.

"On September 27 at about 11:30 p.m. ET, out of an abundance of caution, TVA issued a Condition Red alert, which meant that a breach was imminent." As of 9am Sep 28, Local Emergency Management Agencies had ordered evacuations. As of 4pm, TVA rescinded the Condition Red alert because water levels were receding at about 1 foot an hour. "The Nolichucky Dam peak water elevation hit 1266.0’, which is 9.5 feet over the record elevation of 1256.5’ set on November 6, 1977. The 1.3 million gallons per second [174kcfs] flow rate at 11 p.m. on September 27, more than doubles the flow rate of 613,000 gallons per second [82kcfs] from the previous regulated release in 1977." [TVA_news] To put 174kcfs in perspective, I think the flow rate that wiped out the spillway of the Oroville Dam was about 100kcfs. A Knoxville News Sentinel summary said the "flow reached nearly twice Niagara Falls." But the article was behind a paywall.

0:19 video
This is the Nolichucky Dam in Greene County in East TN. TVA says the dam is still intact, but they continue to assess the situation. 🙏

I think this is the TVA video that was the source for the above post.

 

TVA posted

⚠️ Out of an abundance of caution, we have issued a Condition Yellow for Nolichucky Dam in Greene Co., TN.

A Condition Yellow indicates that the dam is approaching its threshold to withstand excessive floodwater, necessitating immediate action. The dam structure has not failed.

Local county emergency management officials are coordinating evacuations as appropriate.

Extreme rainfall from the remnants of Hurricane Helene is causing record river levels.

Facebook reel

 

I noticed that they are not letting traffic cross the bridge.

wjhl

This is a normal flow over the dam.

Street View, Mar 2023

This is the lowest flow I could find with Street View.

Street View, Nov 2023

This was the highest flow I could find with Street View.

Street View, Jul 2013

TVA
"The dam is 94 feet [29m] high and 482 feet [147m] long."
The hydroelectric equipment was removed in 1972 because the reservoir filled with sediment. I could not determine what the capacity was when it was built. It was built to generate electricity.

Normally, I can find a dam on a river by looking for a skinny line next to a fat line. But in this case the river is as wide below the dam as it is above the dam. That means the river is in a steep canyon.

Satellite

TVA posted five photos with the comment: "We continue to focus on the safety of Nolichucky Dam in Greene Co., TN. Heavy machinery is onsite, placing large rocks to stabilize the area the flood waters scoured away. We are also removing the old powerhouse because of the damage caused by flood waters - the facility hasn't been in service since 1972.
Dam Safety engineers and construction teams are conducting a thorough review of the area and will make any necessary repairs to the dam."

Brett Wanamaker shared

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Digitally zoomed to Facebook resolution

Oct 14, 2024:

TVA posted
Our Dam Safety team will perform a downstream inspection of the Nolichucky Dam in Greene County, TN, on Wednesday, Oct. 16, and if more time is needed, finish the work on Thursday, Oct. 17. The dam's small spillway gate will be opened on Tuesday to lower the reservoir so we can perform the inspection with no water flowing over the main spillway. The dam remains stable and secure.
Ernie Berry: It did not break. A lot of people reported it broke because there was so much water moving downstream. It was reported that 325+ million gallons flowed into Douglas with around 275 million coming from the noli. In places the noli was 1/2-3/4 mile wide and 20-30’ above normal flood height. No one alive today had ever seen the noli like it was that day.

TVA posted five photos with the comment: "Our dam safety experts conducted a thorough inspection of the Nolichucky Dam this week using high-tech equipment, including underwater remote-controlled cameras, LiDar laser measuring equipment, and aerial drones. Engineers will continue to evaluate the information, but the initial inspection determined no major damage to the dam structure. Construction crews continue to repair the dam’s right abutment, which was scoured by the historic flooding from #Helene."

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1917+2002 Tomlinson and 1958+2015 I-95 Q Bridges over Quinnipiac River in New Haven, CT

2927 Tomlinson: (Archived Bridge Hunter; no Historic Bridges; HAER)

2002 Tomlinson: (Archived Bridge Hunter; no Historic Bridges; Satellite, 76 photos)

Q: (no Archived Bridge Hunter; Satellite, 227 photos) The formal name is Pearl Harbor Memorial Bridge

Street View, Aug 2022
This lift bridge carries the Providence & Worcester Railroad as well as four lanes of traffic for US-1. 

Street View, Aug 2022

Street View, Oct 2016

This 2010 photo captured the previous i_95 Bridge.

Emporostheoros via Wikipedia

 

Gregory Grice posted
"CT-1 Crosses the Tomlinson Bridge"
On the afternoon of August 4th, 2024, Providence & Worcester's "CT-1", led by a trio of GEs, crosses the Tomlinson Bridge on the Belle Dock Branch in New Haven, Connecticut. Photo Link: https://flic.kr/p/2qh9Vu7

It took over a half-decade to lay track along the east side of the river so that the bridge track could be used. 40% of the bridge cost was to make it strong enough to carry rail traffic, and that cost was $40m. [nhregister]

ebay
"The original Tomlinson bascule-type drawbridge, along with central railroad tracks dating to 1917, had to be replaced after a runaway barge smashed into one of the old bridge's piers in 1995." [nhregister] 

Note in these photos that the center part of the span has no cables. It must be a suspended span so this bridge is also a cantilever bridge.

CDOT photo via asbi-assoc
"With a span of 515 feet [157m], the main span unit of the new Pearl Harbor Memorial Bridge (PHMB) is the first extradosed cable-stayed bridge constructed in the United States, fully utilizing extradosed pre-stressed cable-stayed technology....The new bridge replaces the previous 1958 structure that was designed for 40,000 vehicles per day; adding critical capacity to accommodate the more than 140,000 vehicles per day."
It replaced a 6-lane bridge with 10 lanes and full shoulder widths.

wsp
The bridge opened Sep 19, 2015.

aecom
"The extradosed system is a hybrid design that is a marriage between a concrete cable stressed girder bridge and a cable stayed bridge. Extradosed type bridges have been successfully constructed in Europe and in the Far East, but the new Q-Bridge will be the first extradosed cable stayed bridge built in the U.S."

The 1917 and 1958 bridges

HAER CONN,5-NEWHA,54--4, cropped
4. View north, bridge partially raised - Tomlinson Bridge, Spanning Quinnipiac River at Forbes Street (U.S. Route 1), New Haven, New Haven County, CT

 

It looks like a trunnion bascule bridge rather than a rolling bascule bridge.

HAER CONN,5-NEWHA,54--14
14. View north of 1976 control house and western leaf in closed position 

HAER_grid

Nivloc, NV: Abandoned Ore Cart Trestle

(Satellite)

Not only is the mine abandoned, so is the town.

Josh Schmid posted nine photos with the comment: "On Monday the 16th, I paid a visit to the famous trestle in the ghost town of Nivloc, Nevada. Nivloc is an old Central Nevada mining town at the end of a rough dirt road, but the reward is the last wooden trestle in Nevada, which once carried ore carts across a ravine. Photos mine."

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Comments on Josh's post

WesternGhostTowns
"Gold discoveries in 1907 led to the creation of this one saloon camp named Nivloc.  This small mining camp was active throughout the 1930s & 1940s.  This recent activity explains the presence of electric motors instead of steam engines."

1862,1971,1997,2021Bridgeport Covered Bridge over South Yuba River

(Archived Bridge Hunter; no Historic Bridges; HAER; Satellite, 1,322 photos)

Street View, May 2012

HAER CAL,29-BRIGPO,1--7
7. General interior view showing arch and truss system - Bridgeport Covered Bridge, Spanning South Fork of Yuba River at bypassed section of Pleasant Valley Road (originally Virginia Turnpike) in South Yuba River State Park , Bridgeport, Nevada County, CA

"Significance: The Bridgeport Covered Bridge is 233 feet [68m] long and was originally built as part of a toll road intended to serve the development of the Comstock Lode around Virginia City, Nevada. It is a Howe Truss bridge with an auxiliary arch." [HAER_data]

 

parks.ca.gov
"Constructed in 1862 by the Virginia Turnpike Company,the Bridgeport covered bridge...is the only remaining single-span covered wooden bridge of this size in the nation." In 1971, "it was closed to vehicle traffic, placed on the national register, and the first major restorative work took place." More work was done in 1997 after a major flood. In 2011 it was closed because timber rot was found during an inspection. The $6.9m restoration project began in 2019, and the opening celebration was Nov 4, 2021.

Shayne Downs posted four photos with the comment:

Constructed in 1862 by the Virginia Turnpike Company, the Bridgeport Covered Bridge is located  on the South Yuba River in Northern California.

A product of the California Gold Rush of 1849, the bridge is believed to be the longest, single-span, wooden covered bridge in the United States with a span of 226ft and width of 16ft. 

It was closed in  2011 due to safety concerns, and this landmark finally reopened to the public on Nov. 4, 2021 after reconstruction.

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I skipped the first 2.5 minutes about the funding. The first phase was stabilization to stop the sagging and prevent collapse. Note the two suspension towers. After the stabilization, they worked on fund raising for the rehabilitation work.

43:04 video @ 3:37

Removing the "covered" of a covered bridge provides good lighting of the truss and arch.

@ 3:58

They installed a temporary bridge inside the covered bridge to support the scaffolding and the bridge. The bridge needed support so that they could replace the arches and top chords. The temporary bridge was also used to raise the whole bridge to accommodate higher foundations. And to make the center of the bridge slightly higher than the ends. That chamber improves the loadbearing capacity of the bridge.

@ 5:36

Nearing completion.

@ 35:16

In addition to the above video summarizing the reconstruction, the state park has an extensive webpage on the rehabilitation. Hopefully, that webpage will remain permanent. A link to the above video was obtained from that page.

This photo was taken after the stabilization phase. We not only see the towers, but also one of the anchors for the cables.

SacramentoValley
This bridge is one of nine covered bridges left in California.

I didn't notice the lateral bracing cables until I saw this photo. Because of the solid walls, wind forces are an issue for this bridge.

asce
"The Bridgeport Covered Bridge is the longest single span covered bridge (230 feet [70m]) west of the Mississippi River."
"In 1862, the price for crossing the Virginia City Turnpike Company's 14-mile section of roadway, including passage over the Bridgeport Covered Bridge, was $0.25 for foot travelers, $0.50 for horsemen, and $6—the maximum toll—for a team of eight animals." [And that was back when you could buy something significant with a penny.]
This bridge is "one of only ten covered bridges remaining in California." [It sounds like California recently lost a covered bridge.]