1964+1999 Chesapeake Bay Bridge-Tunnel (CBBT)

(Bridge Hunter; no Historic Bridges; Satellite)

CBBT Gallery

In 1964, the Chesapeake Bay Bridge Tunnel was opened as a 17.6 mile, two-lane highway. Two of those miles were in two tunnels built between man-made islands because the Navy was concerned that a bridge collapse (accidental or intentional) "could cause a large portion of the Atlantic fleet based at Naval Station Norfolk to be blocked from access to the Atlantic." [BridgeHunter] The rest of the highway was built as a low-level trestle except for two high bridges.

In 1965, it was recognized by the American Society of Civil Engineers as one of the "Seven Engineering Wonders of the Modern World." [EncyclopediaVirginia]

In 1999, a second two-lane highway was opened that paralleled everything built in 1964 except for the two mile-long tunnels. They also rehabilitated the first highway.

CBBT Facts

The 3,780' length for the high bridge must be from where it leaves the low-level trestle to where it rejoins the low-level trestle. I cannot find the length of the navigation channel span. That length is of interest because the following photo shows that the 1964 span needed a truss whereas the 1999 span was done with girders. But I cannot determine if the girders were steel or concrete.

Chesapeake Bay Bridge-Tunnel posted
R E F L E C T I O N S
The original crossing stretches from Fisherman Island as it spans across the Chesapeake Bay to the Virginia Beach shoreline.  The original two-lane facility carried travelers from shore to shore from 1964 to 1999, when it was joined by its parallel partner.  Today, this pictured span continues to carry travelers northbound with two travel lanes (except the tunnels).

 

Bridges Now and Then posted
Construction on the second span of Maryland's Chesapeake Bay Bridge, c. 1972. (MDTA)

Bridges Now and Then posted
"The parallel bay bridge keeps stretching further out into the Chesapeake Bay as this 1971 aerial photo shows. The view, taken from the western shore, includes the present bridge which can been seen to the right of the new span." (William L. LaForce, Jr./Baltimore Sun)

 

Bridges Now and Then posted
Building the Chesapeake Bay Bridge, c. 1950. (Timothy Hyman)

CBBT Gallery

Highway Engineering Discoveries posted

This beautiful shot is the Chesapeake Bay Bridge Tunnel 🇺🇸 !!!

And not just one but two underwater tunnels😍

PHOTOGRAPHER  unknown!!

Jamie Lawson: They are currently adding a second set of tunnels. Currently both bridges reduce to one lane and share a tunnel with oncoming traffic. Kind of scary driving the opposite direction of 18 wheelers at 55 mph only a few feet away.

I remember that my aunt driving with my brother and I over this bridge in the 1960s. I remember that there were signs prohibiting RVs with propane tanks back then. I see they have since relaxed that rule.

Propane regulations are as follows:
Not to exceed 120 gallons in 6 gallon containers or less except for LPG, which is restricted to two 60 pound cylinders LPG capacity (approximately 141 pounds w.c. each) or any combination of cylinders less than 60 pounds LPG capacity with a total of 120 gallons.[CBBT RV]

The bridge is where the bay meets the Atlantic Ocean. It can be scary crossing the bridge, especially when there are high winds. I could not find the info again on the CBBT site, but I read that the police department will provide a driver for those who have phobias concerning bridges and/or tunnels. Maybe I read it in one of the newspaper articles that I read.

CBBT Gallery

To construct it, workers dug huge underwater ditches for two tunnels and lined them with rocks. They then lowered plugged-up pieces of the concrete tunnel into the ditches. To allow cars to drive through, the workers then unplugged the tunnel pieces. [BusinessInsider]

Chris Flint posted
Building the original Chesapeake bay bridge tunnel
Floating tunnel sections out to sink

CBBT Overview

CBBT History

CBBT Timeline at bottom of home page

CBBT via BusinessInsider
[Note that the pilings are being built with precast concrete segments. It is not clear to me how they are joining the segments.]

Cheasapeak Bay Bridge-Tunnel posted
DID YOU KNOW... that the original tunnel segments were constructed in Orange, TX?
Each of these giant tubes measured approximately 300 feet in length and they were floated more than 1600 miles around the Gulf and up the Atlantic Coast to Sewells Point in Norfolk, VA, where they were outfitted before being towed to their final resting place on the Bay bottom.

If you have ever driven on an Interstate highway when they reduce two lanes of traffic down to one lane you know that it doesn't take a lot of traffic for a lane reduction to cause quite a backup. Note that the two bridge highways are still being squeezed down to a single tunnel. Construction was supposed to have started in 2017 to build a parallel tunnel for the Thimble Shoal Channel for $744,987,318. It is supposed to be done in 2022. [CBBT Project]

As I have learned, official web sites can be very bad about current status. I found a Mar, 2018, article that says the Tunnel Boring Machine (TBM) was scheduled for delivery in Oct, 2018. So the schedule has slipped. "One year after boring begins, the machine is expected to surface on the other side." And, no surprise, the cost is going up. This article has a figure of $756m. [PilotOnline] As of Feb, 2019, the cost is still $756m, but the new completion estimate is summer 2023 instead of the original estimate of fall 2022. [PilotOnline-2019]

transportation.gov

The following diagram confirms that 3/4 of a billion dollars is buying only one tunnel. Thus it is not actually relieving traffic backups because you will still get backed up at the other tunnel! "With this new tunnel’s completion, the goal isn’t so much traffic relief but safety redundancies in case a major traffic accident or disaster blocks a single tunnel, according to the Virginian-Pilot." [autodesk]

CBBT Project

This profile diagram is interesting. Below is a tunnel with higher resolution. I now see why they don't use the term cut-and-cover for the tunnel construction. Instead it was fill, sink the tunnel segments, and then fill some more. Does the $3/4b cost include dumping more fill so that they have something to tunnel through? Actually, it seems that the plan is to dig the new tunnel deeper so that it goes through the existing bay's bottom. In fact, the need for more fill and armor stone to do another immersed tube tunnel design favored boring as a more environmental friendly alternative. [CBBT Environmental Impact]

Above at web resolution

This is the first tunnel in the area that will be built with a TBM. The ten tunnels that have already been built are trench-style. "Muck was scooped out the old-fashioned way, bucket by bucket, leaving most of it 'clean' enough to be dumped offshore. But the boring method being used at the CBBT requires the use of additives: foams and other substances common to the oil-drilling industry. They lubricate the cutter head and help sediments – called 'spoils' – flow more easily from the hole. Those additives are petroleum-based, leaving the spoils tainted with contaminants considered hazardous to health." Thus the estimated 50,000 dump truck loads of spoils will have to "go to a landfill equipped with a liner and a leachate collection system." Boring does have the advantage of not interfering with the shipping channel and reducing the risk of damaging the existing tube. [PilotOnline] The above profile diagram confirms that, when the first tunnels were built, ships could easily avoid the tunnel work by using other parts of the bay. But now that the bay is filled with the 1964 trestle, construction activity and ships would have to compete for space in the Thimble Shoal Channel.

Work is being done with the manufactures of the additives to reformulate them so that the spoils from the TBM will be classified as clean fill. [CBBT Solids Disposal]

To avoid water pollution of the bay, they plan to build a water treatment plant on Island 1. (Island 1 is where the TBM launching pit is being dug.) "The treatment plant will be capable of adjusting pH, removing oil and grease, sediments, metals and any other constituents to meet DEQ regulatory requirements. This technology has been used recently on other tunnel projects in the United Kingdom and Seattle, Washington." [CBBT Water Disposal]

The CBBT site has some information about the German-built TBM they plan to use.

CBBT TBM

Screenshot  @ 3:59

The TBM has already dug tunnels in Europe and Asia. [PilotOnline-2019]

May 3, 2024:

1:00 video

CBBT Expansion Update: A tunnel boring machine is up and running again, carving out a new pathway for drivers crossing the Chesapeake Bay Bridge-Tunnel connecting Hampton Roads and the Eastern Shore.

In 2023, crews found a ship anchor while tunneling. It took them about 9 months to remove it and do repairs.

FULL STORY: https://www.13newsnow.com/.../291-2faeb5d2-d5a1-4c13-9ec8...

Insurance should cover the $60m repair cost.

1:52 video @ 0:34

3 drone photos