Friday, June 30, 2017

Illinois Iron Furnace in Shawnee National Forest

(Satellite (41 photos))

Decades ago, I learned there were relics of old iron furnaces in New Jersey. About a decade ago I learned there were some in southeast Ohio. This past year I learned there we some in Kentucky. But today is the first I knew there was one in Illinois. This goes on the "todo" list to get some photos of the interpretive signs.

Jane Netzler posted
So much history in Shawnee National Forest.

Sandy Rutherford Rush posted
Sandy Rutherford Rush Iron ore was smelted here for cannon balls during the civil war and for other uses.

Thursday, June 29, 2017

NS/Philadelphia & Reading 1924, 51-arch Bridge in Harrisburg, PA

NS/Philadelphia & Reading: (Bridge Hunter, Historic Bridges3D Satellite, Street View)

I found the P&R bridge while looking for a satellite image of the Cumberland Valley Bridge.

Its 51 arches are three more than the Rockville Bridge. In the satellite image and in some of the photos I noticed pier ruins west of the bridge on the south side. I presume they are left over from a previous bridge.

HAER PA,22-HARBU,30--1 from LoC
OBLIQUE VIEW, LOOKING NE FROM WEST BANK OF SUSQUEHANNA RIVER. PIERS FROM SOUTH PENNSYLVANIA RAILROAD AT LEFT, PHILADELPHIA & READING RAILROAD BRIDGE AT RIGHT. - Philadelphia & Reading Railroad, Susquehanna River Bridge, Spanning Susquehanna River, North of I-83 Bridge, Harrisburg, Dauphin County, PA
HAER PA,22-HARBU,30--2 from LoC
OBLIQUE VIEW, LOOKING SOUTH FROM EAST BANK OF SUSQUEHANNA RIVER. NOTE INSCRIPTIONS ON PIER AT TOP LEFT. - Philadelphia & Reading Railroad, Susquehanna River Bridge, Spanning Susquehanna River, North of I-83 Bridge, Harrisburg, Dauphin County, PA


Light Rail?/Aban/Cumberland Valley 1916, 43-Arch Bridge in Harrisburg, PA

(Bridge Hunter, Historic Bridges3D Satellite)

Just down stream is another historic concrete arch bridge. ConRail abandoned this bridge because they favored the P&R bridge.

Seamond Roberts posted
It is a good thing that reinforced concrete structures are expensive to tear down and remove because this bridge is now being considered for a light rail service.

Adventures and Pondering has more information about the five bridges that crossed here (3 wood, 1 iron and the current concrete one) and Explore PA History describes the Cumberland Valley.

Update:  The bridge in the postcard doesn't look like this.
Michael Froio Photography posted
The Pennsylvania Railroad’s strategic Cumberland Valley Bridge spanned the Susquehanna to provide the PRR with Main Line connections to the Cumberland Valley Line to Hagerstown, the York Haven Line, and the Harrisburg passenger terminal. The existing bridge is the last of five such spans at this location dating as far back as 1839. The current bridge was completed in 1916 and consists of 45 reinforced concrete arch spans that carried two main tracks between State interlocking and Lemoyne Junction.

John Rose I remember my Uncle Ray (who worked for the railroad in the Enola diesel shop) taking us out on the river in his boat. One time we saw 3 PC or CR E44's running light over the bridge toward Harrisburg. I believe I heard by that time most freight was routed over the Rockville bridge further north and the Cumberland Valley bridge was mostly locomotive moves.
Mike Froio John I think that was always the case. Most freight came up the Enola Low Grade from Columbia. It wasn’t until the Shocks Mills Bridge failed that they started sending big freights over the CV until the Bridge was repaired.
William Frederick They had to put in a new leg to the wye on the HBG side so you could go east. If I remember right it was restricted to 5 mph because it was so sharp.. We would pull east out of Enola to clear LEMO then back up toward Camp Hill then go over the bridge.

Mike Froio shared
James Ridgway Jr. Woefully underused for the last 40+ years. Only used to turn engines at HBG station. Penn Central built wye to replace Shock’s Mills bridge until it was rebuilt after Agnes. Various commuter proposals would see it reactivated; Don’t hold your breath...
John Laughner I better go back and look at my pictures I took of the last circus train that I thought used that bridge in 2016. They held up the train for quite a while to turn around some engines and in the interim a double stack went by. What is confusing me?
Richard D. Zink Due to the demands of traffic disruption, due to Agnes, they put a complete Wye in at the passenger station ( East Leg). Amtrak has left enough track on the bridge [satellite] to enable a passenger train to be turned, and that track and wye still exists by the Harrisburg Hospital and out onto the East end of the bridge. So .. maybe they used that to turn the power.
Raymond Smith John Laughner, Go up to the Bridges cafeteria in the hospital on the 11th floor. The tracks are gone except a short distance on the east shore used for a wye. The circus train you saw was on the Reading Bridge which is still used. The tracks were torn up for quite some time.
A Flickr photo of the upstream side
This is one of several bridges described by Sean Adams.

Because of the high river level, this photo is worth saving. Note the NS/P&R bridge peaking over the top of this bridge in front of the locomotive.
Taylor Rush shared his post
A Pennsylvania Railroad passenger train rolls over what I believe is the Cumberland Valley Railroad Bridge over the Susquehanna River at Harrisburg, Pennsylvania. The massive 43 segmental arch bridge is made of concrete and was built in 1916. Components of the bridge it replaced were incorporated into the construction, mainly the original stone abutments have been encased in the new concrete structure. While currently out of service, there are plans for it to once again see commuter rail traffic.
Stephen Bailey: If that's the Susquehanna River, it's during a big flood.

Note the slanted edge of on the upstream side of the piers. That means they have problems with ice flows on this river. This is also a nice view of the NS/P&R bridge.
Larry Stultz commented on Mike's share

In 1996, ice flows tore some spans out of the Walnut Street Bridge, which was a trail bridge. Some are arguing that this bridge should be turned into a trail bridge.

(new window)



And I fell down the YouTube rabbit hole.
(new window)  This happened in 1938.


1903 Light Rail/Conrail/Pennsy/Panhandle Bridge over Monongahela in Pittsburgh

(Bridge HunterHistoric Bridgespghbridges; Brookline Connection; no B&T; 3D SatelliteBirds-Eye View)

The official name is Monongahela River Bridge.
"Built 1903; raised in 1912-16 grade separation; rebuilt 1982 for light rail." [BridgeHunter] The main span is 351' with 44' of clearance. [pghbridges]

BrooklineConnection via BridgeHunter, License: Creative Commons Attribution-Share-Alike (CC BY-SA)
Replacement of one of the plate girder extensions on the Panhandle Bridge in May of 1955.

The BrooklineConnection also has a photo of the 1863 bridge.

BrooklineConnection, License: Creative Commons Attribution-Share-Alike (CC BY-SA)

AltoonaWorks added
A PRR passenger train crosses the Monongahela River at Pittsburgh on the Panhandle Bridge. This bridge is used by the Pittsburgh Light Rail today.
Pennsylvania Railroad posted
Gilbert Silva shared
A copy without the watermark.
Jackson-Township historical preservation posted
Pennsylvania Railroad train crossing The Panhandle Bridge in Pittsburgh which is now part of Port Authority's Light Rail Transit.
(Photo from Warren Walsack via https://www.facebook.com/groups/421449041235409/)
Fred Leif: Great picture. Has to be between roughly 1963 and 1968. Parkway West is open which required the B&O Railroad to retreat to Grant St from its old terminal at Smithfield St, building a new station opened in 1963. The clean PRR passenger unit consist on a passenger train leaving town, probably the long distance train to St Louis, gives us the clue for before 1968. Penn Central formed that year merging PRR, NYCentral and New Haven. Quickly, the three partners interchanged locomotives in consists and painted everything black with the PC logo.
Great memory of better days for railroads in the 'Burgh

Ian Bowling commented on the above posting
Here’s an older picture of the Panhandle Bridge

A different exposure of the older picture.
BrooklineConnection via BridgeHunter, License: Creative Commons Attribution-Share-Alike (CC BY-SA)
1933 photo looking northeast

Mark Hinsdale posted
"Distinctly Pittsburgh"
If Baltimore & Ohio's "Trailer Jets" between Chicago and Philadelphia were both on time in the late 70's and early 80's, they tended to meet each other in the Pittsburgh vicinity in early afternoon. Such is the case here, as the eastbound CPTT (Chicago-Philadelphia Trailer Train) roars east on the Pittsburgh & Lake Erie main line in Pittsburgh's West End. If you look closely, you can just make out the crewman on the rear platform of the caboose on westbound CHTT, the Chicago Trailer Train on the other main track. Conrail's impressive ex Pennsylvania Railroad Ohio River Connecting Bridge looms large in the background, with the broad Ohio River to the right. August, 1980 photo by Mark Hinsdale
[I think it is the Monongahela River on the right.]

Henry St George Tucker posted two photos with the comment: "Former PRR Panhandle Bridge, now used by Port Authority Transit of Allegheny County Light Rail system."
1

2, cropped

Jimmy Braum posted the comment: "Testimony to the quality of PRR construction. The Panhandle bridge in Pittsburgh took a direct hit by a runaway barge this morning, and is still standing without any preliminary damage visible."
Tim O'Malley Is this portion of the Panhandle now used by Norfolk Southern, or some other railroad?
Jimmy Braum Tim O'Malley PAT port Authority transit light rail.
Alexander Mitchell Last report is Panhandle is still closed as a precaution, however.
Lance Myers Seems to be a recurring problem.

Mark Hinsdale posted three photos with the comment:
"Panhandle Bridge"
To access Pennsylvania Station in Pittsburgh PA, Pennsylvania Railroad passenger trains to or from the "Panhandle" (serving Columbus, Cincinnati, Indianapolis and St. Louis) utilized a bridge across the Monongahela River situated between the Smithfield Street and Liberty Bridges. This "Panhandle Bridge" as it was known, was the route of key PRR trains, such as the "Spirit of St. Louis," the "Penn Texas" and the "Cincinnati Limited." As rail passenger service faded and Amtrak assumed most intercity operations, only Amtrak's "National Limited" continued to use the bridge on a regular basis. Conrail had no compelling freight need for the bridge, and also planned on the eventual downgrading of the "Panhandle" route west of Pittsburgh. The bridge was sold to the Port Authority of Allegheny County in the early 1980's and rebuilt for use by PAT's light rail system. It was quite rare by the time I worked in Pittsburgh (1979-80) to catch a move on the bridge, as the National Limited ran in the wee hours both ways, and was, itself, discontinued by Amtrak in 1979. However, the sporadic freight move still occurred if there was a derailment or maintenance curfew on Conrail's Monongahela Branch that ran along the south side of the river. That was the case here, as a couple of westbound trains used the bridge and waited at "MONON," the junction with the Mon Branch, for a signal to proceed west. It would only be a short time before Conrail terminated its use of "Panhandle Bridge." Today, PAT light rail vehicles cross it frequently. September, 1980 photos by Mark Hinsdale

Steven Schorr Was there a complete wye at the end of this bridge or did it only connect to the mon line northward?
Mark Hinsdale In the 2nd image, you can barely make out the trestle carrying the east eye in the distant background. It was used by commuter trains PRR once operated between Pittsburgh, Homestead and Brownsville.
Tom Umpleby Thank you for post; worked that line to Columbus and been across bridge on truck trains and empty grain trains like the one pictured.

Mark Hinsdale shared
Chris Osterhus Aside from a lack of traffic, the other issue that doomed the bridge, was the rather tight tunnel under downtown...and the station's reconfiguration in the early 1980s. Several tracks, including those used by the National Limited, were combined to make room for the parallel busway.
1

2

3


David Gulden posted
A.B.SHEETS
[This bridge is in the background. The foreground bridge is the Smithfield Street Bridge.]

Wednesday, June 28, 2017

Old Hickory Lock, Dam and Powerhouse on the Cumberland River

(Satellite)
Old Hickory Lock was opened to navigation traffic in June 1954.  The lock chamber is 397 feet long and 84 feet wide.  During normal lake levels, the lock will lift a boat 60 feet from the river below the dam to the lake above the dam.  The lock releases over 15 million gallons of water each time is emptied. [USACE]
USACE photo by Leee Roberts from WorkBoat
The choice of the above photo by WorkBoat was interesting because the article was about shipping Illinois Basic coal for export from Princeton, IN by Norfolk Southern through their Lamberts Point terminal in Norfolk, VA. The alternative export option is by barge down the Ohio and Mississippi for midstream transfer at New Orleans. I don't see how this lock would ever see export coal from any Illinois Basin producer. Maybe there just are not that many pictures of coal barges in a lock.

Old Hickory Lake
Old Hickory Lock at Cumberland River mile 216.2 in Old Hickory, Tennessee, held its grand opening to pleasure boats Sept. 9, 1956. Nearly 10,000 people swarmed the lock and dam structure to see the first pleasure boat named the Avalon lock through.

Pickwick Lock shared
Travis C. Vasconcelos: For September, there are barely leaves on the trees and the folks on the wall are dressed pretty warmly.
Pickwick Lock: Travis C. Vasconcelos Observant. The info was with the photo. Will try to reconfirm the info.

In the Summer of 2015, they dewatered the lock for a month to do standard 5-year maintenance work. This consists of  welding cracks and replacing worn parts. They also "had ERDC (Engineer Research and Development Center) come in and apply a carbon fiber reinforced polymer to the lower gates....The applications of CFRP at Old Hickory Lock will be evaluated to determine the effectiveness of this repair method and how it is impacted by exposure in a wet environment." [dvidshub]

USACE photo by Leon Roberts from dodlive

USACE photo by Leon Roberts from dodlive

One of nine photos shared by Pickwick Lock from a tour of the lock

2 of 7 photos posted by USACE-repair:
a
"The U.S. Army Corps of Engineers Nashville District inspects and performs scheduled maintenance July 27, 2015 at Old Hickory Lock in Old Hickory, Tenn. The lock is empty of water until Aug. 4, 2015 while maintenance crews inspect the lock chamber and perform scheduled maintenance."

b

From lead230:






This is the first time I have seen a lock without a grate over the gears and the other machinery bays. Also note that they store the bulkhead pieces in a "bay" beside the lock so they will be ready for the next 5-year maintenance cycle and for emergency repairs.
Screenshot



BNSF/GN/OTR 1910 Trout Creek Trestle

(Bridge Hunter, no Historic Bridges, Satellite)
There is also a Trout Creek Trestle in Canada. This was the bridge that Google Map's search found.

Steven J. Brown commented on a nice overview photo posted by John Biehn
Back at ya!
John Biehn I can see an outline of myself about half way between photographers and right side of your photo. A line of light behind me.Thanks for your shot.
[It is nice to see that another steam locomotive, SP 4449, is running again. John's photo shows that there were at least 15 passenger cars in the train.]

Tuesday, June 27, 2017

Oakdale Junction: CRL/Rock Island+B&O vs. UP/MoPac/C&WI

Satellite
I learned about this junction from comments on a Facebook posting:
Franklin Campbell And Oakdale just east of there
John LaRochelle Controlled by the C&WI operator at 81st Street Tower per the C&WI Special Instructions and Speed Restrictions in effect February 26, 1974, Speed Limit 30 MPH for trains moving on the C&WI.

I just discovered Chicago and Northern Indiana Railroad Interlocking Towers. It provides a Flickr photo link that has the comment:
A southbound Missouri Pacific caboose hop behind GP50 No. 3521 is seen on the C&WI Dolton Branch about to cross the Rock Island South Chicago Branch at Oakdale. 

This was Mile Post 10.1 on the C&WI's Dolton Branch (approximately 91st Street). Oakdale was a station stop for C&WI suburban trains until 1964. The crossing with the former Rock Island South Chicago Branch (in foreground) was controlled remotely by 81st Street Tower when this photo was taken in the summer of 1981. C&WI's Dolton Branch went from two tracks to four tracks just north of the crossing. The MP caboose hop has used the southward passenger main from 81st Street and is enroute back to Yard Center to tie up after delivering an intermodal train to Canal Street Yard. UP currently owns the C&WI Dolton Branch and only the two freight mains (at left) remain today.

Monday, June 26, 2017

Mississippi Dam and 1913 Powerhouse #19 at Keokuk, IA

(Satellite) There are other views of the powerhouse and dam in the background of photos of the lock.

Between Keokuk, Iowa, and Hamilton, IL, is Mississippi Lock and Dam #19. It also has a powerhouse. In fact, the powerhouse is why it was originally built, and this dam existed a few decades before the other dams were added to the Mississippi to improve navigation.

This dam is about a mile long, and it is rather hard to get a picture of the whole thing. It was the second longest dam in the world when it was built, and it is still the longest dam on the Mississippi river. But, by an historical marker park on the Illinois side, someone has cut the trees so that you can see most of the dam and powerhouse. (Unlike most river powerhouses, this one is perpendicular to the dam rather than part of the dam. That is, it is parallel to the shore.)

20140613 0028c

The organizers of the effort to build the plant searched for years before they found someone willing to attempt the project---Hugh L. Cooper, the engineer who had supervised the construction of the Niagara Falls plant. Since the customers they secured contracts with before they started construction were in St. Louis, the project was also the first to use high-voltage transformers and transmission towers. The Army Corps of Engineers received the lock for the 6-foot (9-foot?) navigation project as a condition of the original construction permit.

When the powerhouse was built during 1910-13, the $25 million project was the largest privately funded construction project in the world. People came from all around the world to witness the construction and the town became known internationally.

Marilyn Settles posted
Lock and dam 19

It was the second largest dam, the largest monolithic concrete dam, the largest hydroelectric power plant with the largest cast iron turbines. (I'm still trying to determine if the largest hydroelectric power plant would also have been the largest power plant.) For comparison, the 1885 Niagara Power Station had 10 AC generators, each rated at 5,000 horsepower (3,700 kw) or 50,000 horsepower. The Keokuk Power Station was rated at 250,000 horsepower and 142MW. Each unit can do 10MW, but there must be switching equipment limitations that limit the plants capacity to 142 instead of 15*10=150.

But when the plant was opened for the 100th anniversary tour, a sign shows 150,000 horsepower and 150MW. The sign is obviously wrong because the horsepower should be more than the KW.

https://www.practicalmachinist.com/vb/attachments/f19/82005d1374711815-tour-keokuk-hydroelectric-dam-imag0282.jpg

https://www.practicalmachinist.com/vb/attachments/f19/82007d1374711859-tour-keokuk-hydroelectric-dam-imag0281.jpg

Tim Ice posted
Keokuk IA. A government photo of Lock & Dam #19, the largest on the Mississippi River.
Jim Colyer: Do any of the dams on the river generate electricity?
Tim Ice: Jim, looking at this picture top to bottom: at top is the Illinois shore. The 119-spillway dam stretches across the Mississippi to the Iowa shore to the only hydroelectric power plant on the river.. 15 generators with 2 house generators. Further to the Iowa shore is the lock complex. Built in 1913.
To the right is the Keokuk-Hamilton (Illinois) bridge, since superseded by a 4-lane non-swing span bridge.
The original plant called for 30 generators, but during construction they found the flow of the river could only handle half that. Consequently only 15 generators were completed.

HydroWorld[1] has summarized the "firsts" for hydroelectricity:
- Longest monolithic concrete dam;
- Largest privately-funded hydropower construction project;
- Largest turbines ever constructed;
- Heaviest rotating weight suspended on a single bearing;
- Largest penstocks;
- Largest inland dry dock;
- Only pneumatically-raised lock gate;
- Only commercial hydroelectric facility on the Mississippi River;
- First long-distance transmission line;
- First high-voltage transformers; and
- First high-voltage insulators.
Another notable feature of the plant - the generator rotor, turbine and shaft assemblies - may be the largest ever built. A single bearing that was four times larger than anything built previously supports each assembly. Engineers were uncertain a scale-up of the roller bearing would be adequate to provide the desired service life for the system. Only half of the turbines were installed with roller bearings. The others were installed using a new type of bearing that had just been invented by Kingsbury Thrust Bearings. These new bearings were so effective that they replaced all of the roller bearings at the plant within the following decade. After a century of virtually continuous operation, none has needed more than minimal repair.
[1]
Lisa Ruble posted
Powerhouse #19 at Keokuk, Iowa
Between Keokuk, Iowa, and Hamilton, Illinois, is Mississippi Lock and Dam #19. It also has a powerhouse.
In 1905 the U.S. Congress passed a bill granting the Keokuk and Hamilton Water Power Company the right to dam the river and construct a hydro-electric plant at the foot of the rapids and to build a new lock and dry dock to replace the canal which had become too small to handle the newer boats of the day.
Construction began in 1910 and when completed in 1913 it was the largest capacity, single powerhouse electricity generating plant in the world. - Waymarking
--
Clip of the hydroelectric power plant and dam at Keokuk and Hamilton on the Mississippi River:
I took this photo from the Illinois side of the Mississippi River - March 2023.
Eric Artman: Historic tidbit #3: The lock at Keokuk is MUCH larger than most Mississippi locks. At 110' × 1200' it's twice as long, enabling easier single locking than the "double locking" involving splitting a tow into two parts used at other locks. It also has a "lift" (level change) of 38 feet, almost four times the common 10' lift. (The impression on a small boater entering from downstream is not unlike a high school basketball team walking into UIUC's State Farm Center for the first time.) To top it off (bad pun fully intended) the upstream gate isn't a swinging pair of "miter" gates from the side, but a huge flat slab of steel truss work that drops underwater when the lock is full and raises like an upside-down guillotine when it's time to lower the lock chamber level. (The method used by boats to stay stationary during level change also differs, but it's just TMI. The boredom index is pretty high right now!)
Lisa Ruble: Do they give tours of the plant?
Amy Christy: Lisa Ruble not anymore 🙁 they closed down after 9/11 and you can no longer get as close as you could. When I was little my mom would take us right up to the fence by the lock and people on the Delta queen gave us their lotions and soaps as souvenirs and a barge once gave us real cotton from down south as it came through. They erected a large fence around the dam and blocked off the entrances so noone but employees can get in. You can only watch from the platform up onto of the control house for the locks or down by the south gages. Noone can go into the powerhouse anymore. I got to walk through a tunnel under the locks and the water trickled down the walls. When we came back we walked over the north gate and it was creepy too 😳
Amy Christy
The powerhouse was a 'first' and still is for many things:
- Longest monolithic concrete dam;
- Largest privately-funded hydropower construction project;
- Largest turbines ever constructed;
- Heaviest rotating weight suspended on a single bearing;
- Largest penstocks;
- Largest inland dry dock;
- Only pneumatically-raised lock gate;
- Only commercial hydroelectric facility on the Mississippi River;
- First long-distance transmission line;
- First high-voltage transformers; and
- First high-voltage insulators.
Eric Artman: Historic tidbit #1: Although south of the principal boundary line, Keokuk and the surrounding territory north of the Des Moines River were left with Iowa when Missouri was admitted as a state so as to provide Iowa with direct access to the Mississippi River below the rapids that were submerged with the construction of the Keokuk lock & dam.
Henry Hill shared
Steve J Crile: In 1837 Lieutenant Robert E Lee helped to survey the rapids between Montrose and Keokuk.

Five photos that Lisa Ruble added as comments.
1
Chief Operator's Room. Showing Control Board and Switchboards, 1914.

2
Here is a look at the interior view of the powerhouse showing the turbines.

3
Pedestal Containing Transmitter and Receiver, located near Generator.

4
During construction.

5


Between Nauvoo, IL, and Keokuk, Iowa, was the Des Moines rapids. The 11-mile stretch of river that falls 22 feet (28 feet in a different source) was the first major obstruction to travel on the Mississippi river. This drop in elevation provides much of the 38 foot head (distance between upper and lower pools of water) for the power station. See a St. Louis Post-Dispatch article for a photo by David Carson of one of the cast iron Francis water wheels that has been retired. (Starting in 2001 the turbines are being replaced with more efficient stainless steel turbines.[1]) This turbine was designed to use a small head but with a high flow rate as opposed to the type of turbine that is used in, say, the Hoover Dam. That article also has a picture of the 15 generators. (Use the arrow in the upper-right corner of the photo to access the other photos.)

Reference link has broken
Comparing David's photo in the Post-Dispatch article of the generator room with an historical photo shows that most of the manual controls are still in place, but they are no longer used. All of the electrical components of the plant have been replaced, but most of the mechanical and civil-engineering components are of the original design, if not fabrication.

The electrical changes include switching from 25 Hertz power to 60 Hertz and using computer-based controls. But much of the 110,000 volt transmission equipment that was developed for this project is still in use[1]. The highest voltage used by the Niagara project was 20kV.

The current use of the hydro power is as a peaking plant because a generating unit can be brought on line in a matter of minutes. Basically, open a gate and sync it to the grid. This allows the plant to be used when one of Ameren Missouri's baseline nuclear or fossil fuel plants has an unexpected outage or during "peak" periods of electrical demands.




Every arch in the dam had a spillway sluice gate. It has been rainy enough this summer that some of the gates are open. A close up indicates that they have several gates open a little bit.

 
Other photos I have seen of the dam seem to use just a few gates that are opened wider.

WGEM
I wonder if they opened the gates wider than normal to get a publicity shot for their 100th anniversary of operation. Many of the photos don't have any gates open at all because the locking operations and powerhouse can handle the river's flow. In fact, each day the Army Corps of Engineers notifies Ameren Missouri how many of the 15 turbines that they can run that day.

I learned that the Iowa side has the wrong angle to see the gates at the top of the spillway. The next time I go, I'm going to have to explore the Montebello State Park because it has a better view of the dam's arches. But it is still hard to see the gate itself. And then I found a closeup of a single arch in the Google image collection.

Hannah, used with permission

I think the flow in this case is just leakage. The dam is 29 feet wide at the top, 42 feet wide at the bottom, 53 feet high, and 4460 feet long. The spillways are 32 feet high. There are 119 piers. Originally just the piers and arch were built to create a bridge. This minimized the pressure on the next cofferdam for the next pier. Then the spillways were added under the arches 5 feet at a time.

http://www.practicalmachinist.com/vb/attachments/f19/82007d1374711859-tour-keokuk-hydroelectric-dam-imag0281.jpg
During the time of the tour, the river was well into flood stage. The gates were open and the water was really churning.


Cross section of water raceway
http://alongthemississippi.org/2013/08/07/how-to-be-alone-2/



https://www.practicalmachinist.com/vb/attachments/f19/82022d1374712794-tour-keokuk-hydroelectric-dam-imag0298.jpg

https://cgee.hamline.edu/rivers/Resources/Postcards/Keokuk1.html


 Impacts of the raised water level

Raising the level of the Mississippi River to create a 60-mile-long lake posed problems along the Iowa shoreline. The company wound up buying out almost half of three towns and moving the residents higher up on the bluff. Another challenge was raising the elevation of nearly 14 miles of track that belonged to the Chicago, Burlington and Quincy Railroad and ran along the Iowa river bank.[1]
The upper pool is 50% full of sediment. The sediment accumulation destroyed mussel beds that were upstream of the dam. This in turn destroyed the perl button business along the river. Actually, perl button is a misnomer. The buttons were made by punching them out of the shells.[2, page 26]

References:


1) Induction into the HydroWorld Hall of Fame in 2013.
2) Keokuk and the Great Dam, John E. Hallwas, Arcadia Publishing, 2001.


Update: Keokuk, Iowa Historians posted 25 aerial photos of the 1965 flood. I highlight the first one and another one that has a roundhouse.
a

b

Randy Sanderson posted
Lock and Dam #19
[Note the powerhouse on the right.]

1 of 10 photos posted by Jay Corbit