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The monitor merrimac memorial bridge tunnel an overview

It is comprised of bridge trestles, manmade islands, and tunnels under the main shipping channels for Hampton Roads harbor.

The monitor merrimac memorial bridge tunnel an overview

It connects the City of Norfolk to the City of Hampton. Chesapeake Bay is an ocean estuary, the lower end of which is about 15 miles wide, and Hampton Roads is about 15 miles from the Atlantic Ocean.

Photo by Virginia Department of Transportation, taken about 1990. The HRBT tunnel holds a place as an engineering milestone: The Hampton Roads Bridge-Tunnel has two 12-foot-wide lanes each way, on separately built structures; the original, now westbound, opened on November 1, 1957; and the eastbound structure opened on June 3, 1976. The HRBT was tolled from 1957 until the second span opened in 1976, and the tolls were removed on the day that the parallel structure opened to traffic.

The monitor merrimac memorial bridge tunnel an overview

Per the 1999 Richmond Times-Dispatch article referenced below excerpt in blue text: The main ferry route ran between a terminal at the end of Hampton Boulevard near the Naval Base in Norfolk to what is now the small boat harbor near downtown Newport News. The total daily traffic between the two locations averaged only about 2,500 vehicles. That more than doubled as soon as the bridge-tunnel opened.

That was a lot of money back in 1957, but no more than that of the ferry. The original HRBT was closed for renovation in fall 1976 after Labor Day, and reopened in spring 1977, and during that project, 2-lane 2-way traffic temporarily utilized the new HRBT, and upon completion of the project, both spans were permanently restored each to 2-lane one-way traffic.

Lane control signals and crossovers allow emergency provision of 2-lane 2-way traffic on one of the spans, if the other span needs to be temporarily closed to traffic. The US-17 Coleman Bridge was re-tolled beginning in 1996 to finance its 4-lane expansion project. The twin tunnels on the Hampton Roads Bridge-Tunnel are each 7,479 feet long, and the roadway is 108 feet below sea level at the lowest point. The bridge roadways are located at an elevation of 17. There are two manmade portal islands to transition the roadways between bridge and tunnel, and the roadways on each are about 1,500 feet long, and the portal islands are built to an elevation of 11 feet above the average high tide sea level.

The Hampton Roads tunnels were built by the immersed sunken tube method, the monitor merrimac memorial bridge tunnel an overview of shipyard-built prefabricated tunnel elements each about 300 feet long, placed by lay-barges and joined together in a trench dredged in the bottom of the harbor, and backfilled over with earth.

A state-of-the-art, computer directed, traffic control system and a video monitoring system are employed to monitor and manage the traffic at the HRBT and its approaches. Air quality within the tunnels is constantly monitored and fresh air is circulated via ventilation fans injecting fresh air into the tunnels.

The parallel facility's trestles have shoulders with a width of 10 feet on the right and 6 feet on the left. The original facility's trestles were built with minimal shoulders about 2 feet wide, and major rehabilitation and widening was conducted in 1998 and 1999 to provide major rehabilitation to the substructure, widening to provide shoulders with a width of 10 feet on the right and 6 feet on the left, and a fully new bridge deck.

During the peak traffic months of June through August, the number of vehicles crossing the Hampton Roads Bridge-Tunnel regularly exceeds 100,000 per day. VDOT news releases and bulletins. So the result was a toll-free highway.

Excerpts in blue text: The bridge-tunnel did catch on over the years. As average traffic exploded from just more than 5,500 vehicles a day in 1957 to more than 81,000 last year, the formerly distinct regions on either side of the Hampton Roads harbor gradually formed a single metropolitan area stretching from Virginia Beach to Williamsburg and containing about 1. The James River Bridge between Newport News and Isle of Wight County began the unification process when it opened in 1928, and other crossings, including the Monitor-Merrimac Memorial Bridge-Tunnel Interstate 664which opened in 1992, pushed things along.

Political and civic leaders have supported the transition by creating business and government groups to represent the entire region.

They also have promoted the Hampton Roads label to replace the older popular names of Tidewater, and Southside for the south side of the harbor, and the Peninsula for the north side. In 1997, the Commonwealth Transportation Board decided to expand the I-664 bridge-tunnel instead of I-64, and that project is in the planning and design stages. The two manmade tunnel portal islands were widened to the west to accommodate the parallel bridge-tunnel project 1972-1976.

Fort Wool is on a manmade island known as Rip-Raps, created beginning in 1818, which was pre-existing land when the HRBT south tunnel portal island was built 1954-1957, with a small earthen causeway that connects Fort Wool to the HRBT south portal island. On the history link below, there is an aerial photo where you can see this location.

The island that Fort Wool sits on is man-made. Known as the Rip-Raps, it was created beginning in 1818 on a shoal and is basically a big pile of rocks.

The island continued to settle after construction of the fort began in 1826 and it was still the monitor merrimac memorial bridge tunnel an overview at the start of the Civil War. A concealed radar tower was built during WWII. A submarine net closed off the harbor entrance between Fort Wool and Fort Monroe. After being decommissioned it was given to the state in 1967 and in 1970 the City of Hampton developed it into a park.

The twin tunnels are each 7,479 feet long, and the roadway is 108 feet below sea level at the lowest point. The I-664 tunnel is 4,800 feet long, and the tunnels on the Chesapeake Bay Bridge-Tunnelare 5,738 feet long on the Thimble Shoal Channel Tunnel, and 5,450 foot long on the Chesapeake Channel Tunnel see respective Roads to the Future articles about those others for the references.

The lengths cited here are from portal to portal. All the tunnels cited cross major shipping channels that handle the largest ships in the world except supertankers.

Here is the explanation, per a review of nautical charts. That means that no dredging for shipping was needed in the naturally deep channel, since it is deeper than the 40 to 45 foot depths in the dredged channels.

With the high volume of commercial shipping and military shipping passing through Hampton Roads, it is logical that the highway tunnel would be built in a manner to preserve the entire width of the naturally deep channel.

  1. In 1997, the Commonwealth Transportation Board decided to expand the I-664 bridge-tunnel instead of I-64, and that project is in the planning and design stages.
  2. Despite the renaming of the ship by the Confederacy, the battle has most popularly been remembered by Americans as "The Battle of the Monitor and the Merrimac". An earlier crash at the monitor-merrimac memorial bridge-tunnel in newport news is cleared, but soundbound traffic is still backed up 3 miles.
  3. That means that no dredging for shipping was needed in the naturally deep channel, since it is deeper than the 40 to 45 foot depths in the dredged channels.
  4. Part of virginia's i-664, the 46-mile monitor-merrimac memorial bridge-tunnel includes a four-lane tunnel that is 4,800 feet long, two man-made portal islands, and 32 miles of twin trestle. The two manmade tunnel portal islands were widened to the west to accommodate the parallel bridge-tunnel project 1972-1976.

The I-664 and CBBT tunnels do not pass under any such wide and naturally deep channel, so their lengths are dictated only by the needs of the manmade shipping channels. Here are scans from a 1976 nautical chart the parallel structure was still under construction thenthat show what is being discussed. Scans of Hampton Roads Bridge-Tunnel area, from a 1976 nautical chart. The numbers on the water is the depth in feet above mean low tide level. Click for larger images: