Rating:
No votes cast

Margaret McDermott Bridge (I-30)

Photos 

Photo taken by Jesse Sharkoman in January 2020

Enlarge

BH Photo #518732

Street Views 

Description 

The Margaret McDermott Bridge is named after the philanthropist and wife of the founder of Texas Instruments. She was the first person to make a personal contribution that ensured Dallas' ability to secure Santiago Calatrava as the designer to meld architectural beauty with functionality for bridges over the Trinity River.

American Bridge is the contractor for erecting the steel arches and bridges working on the Horseshoe Project. The steel is being fabricated in Tampa, Florida at Tampa Steel Erecting Company, Florida's oldest steel company.

Margaret McDermott Bridge is really six separate structures. The Texas Department of Transportation built two freeway bridges, one eastbound, the other west, to carry the Interstate 30 across the Trinity River downtown. Then, at the specific request of Dallas and after much intense lobbying, TxDOT agreed to build two more structures designed by Spanish architect Calatrava.

Each of those is a gigantic arch, one of them stuck on the outboard side of the eastbound freeway bridge, the other on the outboard side of the westbound side.

The pedestrian and bicycle deck of the purely decorative cable-stayed arch for the Margaret McDermott Bridge rests on a supporting protrusion from the TxDOT concrete freeway deck bridge.

The addition of the arches to the sides of the freeway bridges almost doubled the overall cost (115 million for the 2 arches, 120 million for the 4 bridges), even though the arches play no structural role and provide no support whatsoever to the freeway bridges.

Margaret McDermott Is not Much of a Suspension Bridge, Barely a Bridge at All 

Written by Jim Schutze (Dallas Observer)

It is not exactly suspended, in the way one thinks of the Golden Gate Bridge as being suspended. In fact, even calling it a bridge is sort of stretching the point. And before we even get to that, may I share one more thing? I know I said last. This would be the second-to-last thing.

When we say Margaret McDermott Bridge, we really mean four separate structures. The Texas Department of Transportation built two freeway bridges, one eastbound, the other west, to carry the Interstate 30 across the Trinity River downtown. Then, at the specific request of Dallas and after much intense lobbying, TxDOT agreed to build two more structures designed by Spanish architect Calatrava.

Each of those is a gigantic arch, one of them stuck on the outboard side of the eastbound freeway bridge, the other on the outboard side of the westbound side. Do you ask why? Good.

Originally, a group of very wealthy and influential women including some generous patrons of the arts had hoped to see an entire succession of Calatrava suspension bridges up and down the river, which would have made Dallas the most Calatrava city on earth — the Calatravaest. That idea was trimmed to three bridges, then two.

The second, the MMB, originally was to be a true suspension bridge. But that would have cost a ransom somewhere north of $300 million. Since no suspension bridges were actually needed to get across the Trinity and since Dallas already had one ornamental suspension bridge anyway in the Margaret Hunt Hill Bridge, the state and the feds balked at doing another.

The MMB, designed as a cost-saving compromise, was always intended to be a regular, old, off-the-shelf, highway department, pier and beam, concrete, platform bridge with two big arches stuck on the sides to make it look like a suspension bridge from 10 miles away.

In public statements, the cost of the MMB has always been pegged at $115 million by officials who never fail to mention that $5.5 million of that money came from private sources. So that seems like a big savings — only $109.5 from the taxpayers compared with something like $300 million.

I cannot tell you that anyone has ever deliberately misled the public about this. I can tell you that the price — $115 million — has always been tossed around pretty nonchalantly as the amount paid for the MMB.

But then we have a question, do we not? There are four structures down there that all fall under the name MMB. So which ones and how much of them did the $115 million pay for?

The answer is that the $115 million paid for the Calatrava arches only. The cost of the actual freeway bridges between the arches — the ones that carry 11 lanes of car and truck traffic across the river — is seldom if ever mentioned.

In fact I found that the cost of the freeway bridges, or, as I call them, the bridges, was buried deep in the overall multi-billion dollar cost of what the highway department calls the “Horseshoe Project,” which involves the rebuilding of all of the tangled expressways where they come together in downtown Dallas.

It took a while, but TxDOT was nice about finally digging up an estimate for me. The freeway bridges between the arches, a spokesperson told me, cost approximately $120 million.

So, two points, if I may. The addition of the arches to the sides of the freeway bridges almost doubled the overall cost, even though the arches play no structural role and provide no support whatsoever to the freeway bridges. They are decorations, or they would not be there.

Secondly — and, again, I’m not saying there was ever a deliberate deception — the savings doesn’t come out looking quite as slick when you realize the cost was $235 million total compared with $115 million. Given what we seem to be dealing with now in terms of structural issues, maybe we would have been smarter to push the extra money out there and build an actual suspension bridge

https://www.dallasobserver.com/news/dallas-mcdermott-bridge-...

Facts 

Overview
Stringer bridge over Trinity River/Ih 35e on Ih 30 Wbml
Location
Dallas County, Texas
Status
Open to traffic
History
Built 2016
Builders
- American Bridge Co. of New York
- Santiago Calatrava of Benimŕmet, Valencia, Spain
- TXDOT
- Tampa Steel Erecting Co.
Design
Series of Prestressed Stringer Girders With 2 Decorative Cable-Stayed Arches Bridges for Pedestrians
Dimensions
Length of largest span: 250.0 ft.
Total length: 4,269.2 ft. (0.8 mi.)
Deck width: 149.9 ft.
Also called
Tom Landry Freeway
Approximate latitude, longitude
+32.77036, -96.81776   (decimal degrees)
32°46'13" N, 96°49'04" W   (degrees°minutes'seconds")
Approximate UTM coordinates
14/704402/3627937 (zone/easting/northing)
Average daily traffic (as of 2016)
130,926
Inventory numbers
TXNBI 180570106804526 (Texas bridge number on the National Bridge Inventory)
BH 96599 (Bridgehunter.com ID)
Inspection report (as of August 2017)
Overall condition: Good
Superstructure condition rating: Excellent (9 out of 9)
Substructure condition rating: Excellent (9 out of 9)
Deck condition rating: Excellent (9 out of 9)
Sufficiency rating: 84 (out of 100)
View more at BridgeReports.com

Update Log 

  • February 21, 2022: New photos from Bambi Sharkoman
  • February 17, 2022: New photos from Bambi Sharkoman
  • February 15, 2022: New photos from Bambi Sharkoman
  • February 9, 2022: New Street View added by Bambi Sharkoman

Sources