1967 Mississinewa Dam on Mississinewa River near Peru, IN

(Satellite)

This is one of three flood control dams (JE Roush, Salamonie, and Mississinewa Lakes) built in Indiana to stop storm water from flowing into the Wabash River during a storm. After a storm passes and the Wabash River returns to a more normal flow, they release water from the reservoirs. While releasing the water, the flow in the Wabash River is comparable to what it is during a rainstorm.

Street View, Apr 2025

Street View, Apr 2025

Facebook Reel

This is what a more normal outlet flow looks like.

Adam Adamczyk, Oct 2023

usgs

Mississinewa Lake, U.S. Army Corps of Engineers, Chicago District posted

📣 UPPER WABASH BASIN UPDATE 📣

The U.S. Army Corps of Engineer is adjusting operations at JE Roush, Salamonie, and Mississinewa Lakes due to the decrease in downstream stages. Downstream stages on the Wabash River crested on Sunday, following the heavy rainfall last week, and have continued to decline.

Effective 18 August 2026, USACE will begin increasing outflows from the reservoirs as stages have begun to fall to safe levels downstream. Releases have increased to approximately 1,500 cfs at JE Roush Lake with Salamonie and Mississinewa to follow as downstream conditions allow. 

The reservoir and dam are operating as designed. This is a planned and controlled operational adjustment based on current conditions.

Thomas Beeching: Why was JE Roush selected first? Didn't that watershed receive the least amount of rainfall?

Mississinewa Lake, U.S. Army Corps of Engineers, Chicago District: Thomas Beeching Roush typically takes priority due to their large watershed and smaller capacity. They fill up rather quickly and require the first release availability. Second priority typically falls to Mississinewa.

Shirley Hileman: What did the Wabash crest at in Peru?

Mississinewa Lake, U.S. Army Corps of Engineers, Chicago District commented on Shirley's comment
as all three lakes start to release, well bring it higher than the 11.83 feet that it hit last Thursday.

The dam is 8000' (2.4km) long with a hydraulic height of 122' (37m) and a structural height of 140' (43m). The emergency spillway is 1550' (472m) with a discharge capacity of 122.4kcfs. The normal storage is 75,200 acre-feet and the maximum storage is 368,400 acre-feet. [LakesOnline]

I could not find the capacity of the outlet works. My guess is around 5kcfs.

I think this is the emergency spillway. The water is then allowed to flow across farmer's fields until it reaches the Wabash River.

Satellite

The USACE had another lesson about building a dam on a karst landscape without a foundation cutoff wall. They had to spend a lot of money later to add the cutoff wall.

keller
The dam had seepage issues. So, the USACE had to add a cutoff wall up to a depth of 235' (71.6m).
[Given the device in the photo, they are using a hydromill to build a diaphragm wall.]

Two pedestrian Bridges over White Lick Creek in Plainfield, IN, and crane operation

North: (Satellite) 

South: (Satellite, it is too new to be on the map when I published. It is south of the restroom)

Facebook Reel

Scott Tucker: That " crane operator" is rough as a cob.

Kelly Rhudy: Scott Tucker yea cuz that’s an easy job ….

Joe Wallin commented on the above reel, cropped

This YouTube short explains the history of the 1920 truss. He confirms it's a pin-connected truss.

I was surprised how much the bridge was swinging back and forth in the above reel. Scott's comment above indicates I was correct to be surprised. I spent several days watching an LTM 1450-8.1 crane lift steel beams over the building below to construct a commons area in the Downers Grove South courtyard. As you can see, the boom is short, but the luffer jib is long. That luffer configuration allows them to lift the beams over the building and reach the far side of the courtyard by lowering the luffer. Since they use a short radius when hooking up to a beam in the parking lot, the cable is long because of the length of the luffer. It struck me that I never saw the load swing back and forth, even after it was slewed over the building. I watch the lift of several steel beams over the course of several days and every time the hook was lowered over the beam with no pendulum action.

20200728 2489

Then one day I got there early so that I could watch them raise the luffer for the workday. It took about 5 minutes.

20200805 2610

Since they were ready with the crane before the riggers were ready to work, the oiler got some time in the cab for practice. He demonstrated that the hook does want to swing back and forth. And he was unable to stop the pendulum action. When the operator got back in the cab, the hook immediately quit swinging. So, I agree with Kelly that it is hard to learn how to avoid swinging the load. But I agree with Scott, why would an operator that has not learned how to stop the swing be allowed to do an important lift. 

These two screenshots show how much the hook was swinging. It is now clear which object on the parking lot the oiler was aiming for.

20200805 2611

20200805 2611

There was already a pedestrian bridge that connected the trails on both sides of the river. But the truss bridge allows them to easily get their lawnmower to the other side of the park.

Street View, Jun 2016 (Satellite)

1913-2027 Ohio Edison Dam on Cuyahoga River at Akron, OH

(Satellite)

ebreedon, May 2022

GreatLakesMud, Credit: Summit Metro Parks
It was built in 1913 as a hydroelectric plant. It quit generating in 1958 but continued to provide cooling water for a coal-fired power plant until 1992. "Remarkable geology surrounds the dam, with the Cuyahoga River dropping 200 feet [61m] in elevation in less than two miles. The dam interrupts the potential for 2.5 miles of continuous Class III – Class V whitewater."
[I could not find the capacity of the hydroelectric plant.]

GreatLakesMud, Credit: Cuyahoga Falls Historical Society

GreatLakesMud, Credit: Summit Metro Parks
"Originally, the Cuyahoga River coursed through a series of small waterfalls, which were flooded after the construction of the dam."

metro-parks
This cascade is 22' (6.7m) high. [Even with a strong water flow, to me those drops seem rather dangerous to raft.]

metro-parks, Credit: volunteer Jeff Hill
"The power dam was 57 feet [17m] high and 420 feet [128m] wide. The dam pool extended over a mile upstream when flooded, provided cooling water for a coal-fired power plant built in 1912. Water pulled from the top of dam was sent a half-mile down stream to a hydroelectric generating plant. "

metro-parks-2
This article argues why the dam should be removed.

Facebook Reel

The initial estimate for removing the dam was $50m. The estimate is now $100m. [KentStateNewsLab]

1925,1987 5mw O’Shaughnessy Dam and Birdge on Scioto River upstream from Columbus, OH

(Satellite)

The dam was built in 1925 as a water supply dam. [kiddle]

DelawareOhioHistory
The dam cost $1.54m and holds 6.3 billion gallons of water. 
"The project was of such a scope that a contractor was hired that had experience building metropolitan skyscrapers; the Thompson-Starrett Company was responsible for such structures as the General Motors Building in Detroit and the landmark Woolworth Building in New York City."

It is a fixed-crest dam (no gates on top). The current bridge doesn't appear to have any girders, just slabs.

Dave Neel-Surrena, Mar 2018

The dam is 1510' (460m) long with a spillway width of 802' (244m). The max discharge rate is 261kcfs. [NewarkAdvocate] 

261kcfs is a lot. I wonder how much the downstream river valley can handle without flooding. As the river flows to Columbus, there are some rather narrow spots in the river.

ColumbusLibrary, 1957 photo by Matthew Mosbacher Sr., no copyright
"Water spilling from the O'Shaughnessy Dam during the 1957 flood. The dam was completed June 1, 1925.  The reservoir, created by damming the Scioto River, provided a needed water source for the city. The reservoir is 912 acres in size and has 18.4 miles of shoreline. Maximum depth is over 40 feet near the dam, although much of the water is 20 feet or less."

DelawareOhioHistory, © JEFF HINCKLEY
A 5mw power plant was installed in 1987. It was abandoned in Feb 2017. $15.3m was approved in 2023 to refurbish the plant to produce electricity again.

The power plant can't be used all of the time because sometimes the flow in the river is too low. Since the main function of the dam is water supply, I expect they can run the plant only when water is going over the spillway. But of all the photos and videos I looked at, this was the only one that had a dry spillway. But photos are probably biased towards spilling water because they are more impressive. In general people will go out of their way to capture a big flow over the dam.

VisualOhio
This source puts the capacity of the spillway at 100kcfs. Although the author is careful to note that the information was provided by Google Bard AI.
[I presume that the Ferris wheel in the background is part of the Columbus Zoo and Aquarium. But I could not find that wheel using street view.]

The river downstream does appear to have good capacity because the rainstorm on Aug 21 flooded I-70 a little east of here.

usgs

Originally, the dam had a closed-spandrel arch bridge across the top.

W E Ayres postcard #123890 via Columbus Metro Library via Bridge Hunter

This was the post that motivated this research.

Facebook Reel

Victoria Vara: This dam doesn't have flood gates. It's just rolling over the normal crest.

Erie Canal Guard Gates and 1911 Farm Bridge west of Albion, NY

Gate: (Satellite)

Bridge: (Archived Bridge Hunter; Bridge Hunter; Historic Bridges; Satellite)

Erie Canal overview

A Facebook comment called this Bowman's Farms Bridge, but the webpages agree that it is Lattins Farm Drive Bridge. The farm probably has had multiple owners.
 

Dennis DeBruler commented on Charlie's comment below
The gates and bridge appear to be extant, https://maps.app.goo.gl/AeGc8nifTwUrmwrQ6.

Craig Lacy posted
Set of guard gates near Medina.  They do come in handy from time to time.

Charlie Ricker: This was just west of Albion; the bridge overhead went to Bowman's farms.

HistoricBridges
"This bridge stands out among the many Erie Canal historic bridges as an example of a bridge that is not either a vertical lift bridge or a double-intersection Warren through truss. Instead, this is a multi-span Warren pony truss. The bridge also has a narrower deck width than most Erie Canal bridges. The bridge serves a dead-end road, and perhaps the light use such a bridge would be expected to receive explains why the bridge is narrow. The narrow width may also account for why a different truss design was chosen."
[The map location on this webpage is wrong. The bridge is a few blocks further west were a road crosses the canal and goes to a loop of road.]

1957+1991 I-476 (Pennsylvania Turnpike Extension) Lehigh Tunnel and New Austrian Tunnelling Method (NATM)

North Portal: (Satellite)

South Portal: (Satellite)

North Portal:

Street View, Jul 2024

South Portal:

Street View, Jul 2024

This 4,461' (1360m) tunnel goes under the Blue Mountain. [GribbleNation, this webpage has photos about adding the second tube.]

This source specifies 4,300' (1311m) for the 1957 northbound tube and 4,381' (1335m) for the 1991 southbound tube.

This is another view of the north portal to emphasize the retraining walls. They had to remove the side of the hill to make room for the new 1991 southbound tube.

Street View, Jul 2025

mcall
"Construction of the second tunnel in 1989."

Daniel Kauffman posted five photos with the comment:

Pennsylvania Turnpike's...Lehigh Tunnel, Lehigh and Carbon Counties.

A foggy ride into the mountains ⛰️ 

 The only road tunnel in Pennsylvania traversed by the Appalachian Trail is located under a major ridge of the Appalachian Mountains (Blue Mountain) that separates the Pocono Mountains Region and the Lehigh Valley Region. This tunnel consists of a North bound and a South bound tunnel, constructed at different times. My photographs are of the Northern tunnel, constructed in the 1950's and is a drill and blast, rectangular-shaped tube. This tunnel is lined with tiles that have become quite a driving distraction. Tens of thousands or about 20% of the tiles have become dislodged, some say due to maintenance policies, others mention seismic activities. The Southern constructed in the 1990's and is a New Austrian Tunneling Method, oval-shaped tube. This tunnel had a  bizarre occurrence in 2018, 70 year old truck driver Howard Sexton was mortality wounded by a 10 foot section of metal electrical conduit pipe that became dislodged because of corroded steel straps that fell and crashed through his cabs window. Howard was able to control his rig and pulled to the side a mile down the highway. Blue Mountain tunnel system....

Dave Costello: I always wear a set of amber or clear SHOOTING safety glasses going through the NB side. If you want to know why, just take a look at the ceiling at all of the missing tiles and then ask yourself what happens when one of them hit your windshield while you are doing 55+ mph. Pretty obvious what’s going to happen. You are going to get a face full of glass. I also firmly believe that the Pa Turnpike Commission doesn’t want you to know this. IYKYK

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Since there is a curve in the road and the oval portal is on the right side, this is the north portal.

Pennsylvania Things posted

BREAKING: Pennsylvania officials remind motorists that the Lehigh Tunnel is the only place where 70 mph traffic collectively agrees to slow down for absolutely no reason.

Drivers who were just fighting for their lives on the Turnpike suddenly enter the tunnel, become model citizens, grip the wheel at 10 and 2, and stare straight ahead like they’re taking their driver’s test again.

Then the second daylight appears, everyone immediately returns to felony speeds.

The Lehigh Tunnel remains undefeated.

I can't determine if this was the original north or south portal.

dr-sauer, this webpage has several photos about the construction work done between 1987 and 1991.

New Austrian Tunnelling Method (NATM)

The reason why the 1991 tube has an oval opening instead of the rectangular opening of the 1957 tube is that it used the New Austrian Tunnelling Method (NATM). NATM is still a drill-and-blast technique, but it uses techniques that reduce the cost of the support liner. First of all, only short segments are done at a time, and the design of the support liner is changed to reflect the rock that was bored through. The contract needs to be flexible to change the design as the rock conditions change. Secondly, the tunnel is removed in layers.

aates

After a segment is drilled and ballasted, a venilation system at the crown of the tube is extended to removed the harmful gases and dust. Then the debris generated by the blast, called muck, is removed.

aates
"The process of applying a thin layer of mortar on the excavated area of the tunnel is called face sealing concrete. This layer is imperative to prevent the loose material from falling. Depending on the geological conditions and stability of the exposed surface, a minimum of 30 mm to a maximum of 50 mm thickness of sealing shotcrete is typically applied."

The bore is allowed to deform to reduce stresses in the rock. But 3D instrumentation is used to measure if the deformation exceeds thresholds. If the deformation is too much, "timely interventions" are implemented. 

aates

Then a "lattice girder" is installed and a layer structural shotcrete is applied over the steelwork. The thickness of the layer is determined by an analysis of the deformation data.

aates

Finally, rock bolts are installed through the shotcrete into the surrounding rock.

aates
"The primary purpose of rock bolting is to “stitch” the rock mass and the shotcrete lining together. This integration helps control displacement and discontinuities, and improves the overall load-bearing capacity of the tunnel cross-section."

aates includes a table that compares Tunnel Boring Machine (TBM) with NATM. NATM can be better for shorter tunnels and/or tunnels with complex (variable) geology.