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.]

1978 Burnsville Dam on Little Kanawha River upstream of Burnsville, WV

(Satellite)

Street View, Oct 2025

"The dam became operational for flood control in December 1978. The dam is a combination of earthen fill and concrete structures that is 90 feet [27m] high and 1,400 feet [427m] long. The earthen fill section has an impervious clay core. The concrete section contains the spillway and outlet works." [USACE]

Aug 21, 2026:

Facebook Reel

I couldn't see any water flowing under the Radial Gates. Then I noticed the outlet works down at the river level. 

They have five sluice gates and three valves. The spillway is 126' (38m) wide. [BattleCreekEnquirer]

The reservoir was at conservation pool, so they are dumping the water from a rainstorm.

USACE

The outlets pass enough water that the public areas, including a couple of campgrounds, are closed until Aug 24. Hopefully, they cleared out the campgrounds before they were flooded. [Facebook]

Here is an example of a campground in Indiana that did not have enough warning to get their campers out.

1955 Lewisville Lake Dam on East (Elm) Fork Trinity River upstream of Dallas, TX

(Satellite)

USACE

The USACE completed this dam in 1955 to replace the Lake Dallas Dam. Construction of the Lake Dallas Dam began in 1928 as "the principal source of municipal water for its owner, the city of Dallas." It was 80' (24.4m) high and 11,000' (3.4km) long. This dam is 125' (38m) high and 33,000' (10km) long. "The huge lake that resulted was thirteen miles long, had a 183-mile shoreline and a capacity of 436,000 acre-feet at an elevation of 515 feet, and covered almost one-fifth of Denton County." [tshaonline]

This twdb source has different capacity figures than the above source has. Since the main functions of this dam are water supply and flood control, lake capacities are important.

twdb
The elevation at the top of dam is 560 feet above mean sea level, while the maximum designed water surface is at the elevation of 553 feet above mean sea level. At top of flood control pool (crest of emergency spillway), at an elevation of 532 feet above mean sea level, the lake covers 39,170 acres and stores 989,700 acre feet of water. At the top of the conservation pool, at an elevation of 522 feet above mean sea level, the lake covers 27,175 acres and stores 598,902 acre feet of water.

To add to the confusion, this source says the dam "holds back 2 million acre-feet, or 2.5 billion tons [0.6 trillion gallons], of water when the lake is full."  The normal definition of "full" is the conservation pool, 522'. They must be defining "full" as the maximum designed water surface, 553'. Note that 31' (9.4m) of water would be flowing over the spillway and the water would be within 7' (2.1m) from the top if the reservoir ever got this full.

Fort Worth District, U.S. Army Corps of Engineers posted five photos with the comment: "Construction of the Lewisville Lake dam was completed in August 1955. For more than 70 years the lake has been providing flood risk management for the Lewisville area and downstream communities along with supplying water to neighboring communities and recreational opportunities."

1

2

3

4

5

This is not the spillway. It is the outlet.

YouTube Short

This is the spillway. I had a hard time finding it because it is way off to the side. Probably so that the water will flow over more competent riverbank soil. In fact, looking at a satellite image, under a thin layer of soil is bedrock.

The spillway apron obviously needs repair work. I wonder how many times water has flowed over this spillway. (I looked through past Google Earth images. A few times, and the apron has been torn up and repaired before.)

Google Earth, Jun 2022 (Satellite)

The next Google Earth images shows that they had started much needed repair work on the spillway.

Google Earth, Jun 2023

The latest image available shows that they are still working on it.

Google Earth, Oct 2025

Dec 12, 2015

DallasNews
"Sandbags and tarps have been deployed in an attempt to prevent further erosion of a 160-foot-long slide on the Lewisville Dam. To engineers, the slide’s proximity to another major one that happened in 1995 suggests instability that could threaten the dam’s foundation."
The Dam Called Trouble
[Read the article, there were too many issues for me to summarize. Of note, there was a sand boil and piping during a rainstorm in an area that had leaked for years. Fortunately, the operations team was able to stop the piping by placing "a one-layer ring of sandbags around the sand boil, allowing the pool of water inside to rise about six inches. The method is supposed to equalize the pressure and prevent the water and soil particles from expanding."
Also of particular note, a breech "would submerge downtown Dallas in roughly 50 feet of water, the Corps estimates, causing more than $21 billion in property damage....“It would be a much bigger magnitude to the Dallas area than Hurricane Katrina was to New Orleans,” says Vazquez [The dam's operational manager]."]

$39.1m was awarded in 2019 to improve drain seepage areas. [news_2019] (I wonder what was used for the core for this dam. Or did they not bother to put a cutoff wall in the foundation. More drains sounds like a patch, not a fix.)

$76.1m was awarded in 2022 to repair the spillway. This time they will anchor the apron to the underlying bedrock using post-tensioned anchors. [news_2022]

RED ALERT: bogus AI. If they are going to use AI, I guess it is good that it is really bad so that you know it is AI. The "photo" itself is obviously bogus because many of the diagonal rods don't make sense. But when you compare the "photo" to the real spillway, it becomes absurd.

OceanCraft RC posted

At Lewisville Lake Dam in Texas, engineers are strengthening the spillway by drilling more than 70 high-capacity post-tensioned anchors through the concrete and deep into the underlying bedrock.

The anchors essentially lock the spillway to the rock below, increasing resistance against uplift and sliding when enormous water pressures act beneath the structure during floods.

1920 Germantown Dam on Twin Creek near Germantown, OH

(Satellite)

Aug 2026

The outlet tubes are full, and the water is coming out under pressure.

Facebook Reel

It looks like Ohio got some of that rain that caused record flooding in Central and Southeast Indiana.

WaterData

TheDaytonMagazine
"How the Germantown Dam is made up"
This is one of five dry dams that was built after the 1913 flood to reduce flood damage 

TheDaytonMagazine

Three c1930 photos of the dam

OhioMemory, cropped
"A conservancy road goes across the top of the dam. The dam was built to temporarily store floodwater and has no gates or permanent pool. It is 1,210 feet long and 100 feet high. There are two concrete conduits through the base of the embankment at the north abutment. The conduits are sized to discharge a peak flow during an Official Plan Flood that can be handled by the flood protection levees and channels downstream. The remainder of the floodwaters are temporarily stored behind the dam and released over time. An emergency spillway is located in a low area through the left abutment north of the dam."

At first, I could not find the spillway. But the above "An emergency spillway is located in a low area through the left abutment north of the dam." allowed me to find it.

Satellite

It appears that the 31.5' depth in the above water data chart is about twice as high as the conduit. The dam is 100' high.

mcdwater_2025
"Germantown Dam is an earthen embankment that spans 1,210 feet across Twin Creek....It’s capable of storing up to 34.55 billion gallons of floodwater and managing it through two massive conduits — each 546 feet long, 9.1 feet high, and 13 feet wide — that run through the bottom of the dam."

mcdwater_2025
[I agree that the concrete needed to be repaired.]

mcdwater_2025

It is the right descending conduit that was repaired.

dayton447now
The flood control project included 55 miles of levees and channelization of parts of the river to accommodate the full output of the conduits.

More importantly than the dam being 100' high, the spillway is about 80' high. So, a water depth of 31.5' is a rather small fraction of the reservoir since the capacity increases as the water goes up because the water spreads out over more land.

1960/62 Farmersville Quad @ 24,000

$3.2b Storm Water Diversion from Red River Around Fargo, ND

Target for completion is 2027.

8:52 video @ 4:27

New York Lower Manhattan $4b or more Flood Protection

I've seen information about storm protection being done further north on the east side of Manhattan, but now I can't find that info.

The official name of the project is Lower Manhattan Coastal Resiliency. 

nyc

In addition to flood walls and gates, the project includes a pumping station and sewer work.

nyc

Economic Development Corporation
The video below provided a figure of $4b. The source says $5b to $7b.

Economic Development Corporation

Facebook Reel

Turtle Creek Flood Gates near North Braddock, PA

(Satellite)

I was able to find the location of the flood gates because of the George Westinghouse Bridge on the left side of this photo.

Michael Pearce posted
Flood Gates

Bill Ireland: 2008 or 2009 last flood

James J Valentine: I'm thinking the 3 Pumps were capable of 1 million gallons per minute. Electric came from the Power Plant in the center of the plant.

These gates are closed when the Monongahela River is getting too high. They stop the flood water from flowing back up Turtle Creek and flooding the Westinghouse Plant. The 1m gpm pumps are needed to move the Turtle Creek storm water into the Monongahela River when the gates are down.

1913,1993 Colorado Boulevard Bridge over Arroyo Seco in Pasadena, CA

(Archived Bridge Hunter; Bridge Hunter; no Historic Bridges; HAER; Satellite)

HAER CAL,19-PASA,11--2
2. OVERALL VIEW OF BRIDGE, LOOKING NORTH. THE PIONEER BRIDGE CAN BE SEEN BEHIND THE OLDER BRIDGE. - Colorado Street Bridge, Spanning Arroyo Seco at Colorado Boulevard, Pasadena, Los Angeles County, CA

"Significance: The Colorado Street Bridge is an eleven-arched reinforced concrete structure, the longest and highest bridge of its time. It was the first high bridge across the Arroyo Seco, and is an important visual landmark in Pasadena. Through its design and construction, the bridge represents the advancing concrete technology of the twentieth century and the ornamental aesthetic of the late nineteenth century. The Colorado Street Bridge was designed by one of the nation's foremost bridge engineers, and constructed by a well known California builder. The local community played an important role In planning and funding construction." [HAER_data, my emphasis in bold]

I added the "cement" label to these notes since this bridge was a landmark concrete bridge in terms of length and height.

Street View, Oct 2014

Carlos G. Lucero posted, cropped

In the arid southwest of the United States more than anywhere else, the growth of a city was dependent upon water. Pasadena was founded where it was exactly to take advantage of a reliable water supply, the Arroyo Seco ("Dry Gulch" in English). It was a reliable source of water in a rather dry environment.

However, the Arroyo Seco was also problem, it was deep in a steep sided canyon. This meant that Pasadena was physically isolated from its western neighbors. Travelers would have to make long detours passable crossing north or south of Pasadena.

This was finally changed by James Scoville. He had been the Vice President of the Elgin Watch Co., President of the Prairie State Bank, and a trustee of what would later be known as California Institute of Technology. He built a pleasure garden on the bluff above the Arroyo Seco which went down the slope of the canyon walls to the stream itself. There he built a small dam and pump house. The top of the dam served as the eastern abutment of a wooden bridge, the first connect Pasadena to the western side of the Arroyo. Scoville Bridge was still in service when the much larger and grander Colorado Blvd. Bridge was built above it.

[David Kimbrough via ArchivedBridgeHunter]

The Arroyo Seco doesn't supply much water today. Given the channelization, today it is a stormwater drain.

Street View, Dec 2024

California Historical Society CHS-7799 via USC Digital Library via BridgeHunter
"Scoville Bridge is visible beneath."

Pasadena Orange Growers Association via BridgeHunter

Postcard via LAist via BridgeHunter

Postcard provided by Mike Ward and Joe Sonderman via BridgeHunter, they uploaded a lot of postcards.

So which one is the suicide bridge?

Carlos G. Lucero posted
Infamous “suicide bridge” Pasadena California