History of the Cape Cod Canal and bridges

Describes the history of the Cape Cod Bridges and their construction, their impact on the economies in the region, and their importance moving forward. This history has been sourced from the Army Corps of Engineers.

Table of Contents

Origins of the Cape Cod Canal

The Cape Cod Canal, a century-old engineering marvel, holds a rich history and significance for the region. The idea of a canal through this area began at Plimoth Colony in the 1600s, driven by the need for economic trade, life-saving measures, and military security.

Two rivers flowed through this area before the Cape Cod Canal existed. The Mamomet River, later called the Monument River, flowed into Buzzards Bay in the southwest. The Scusset River flowed into Cape Cod Bay in the northeast. Approximately one mile of land separated these two rivers.

To trade with the Dutch and the local Wampanoag tribe, the Pilgrims established a trading post in 1627 along the Mamomet River. To reach this trading post, it was preferable to travel by water by sailing down the coast, along the Scusset River, and then portaging three miles on land. This was preferable to traveling twenty miles entirely by land. While an all-water route would have more easily facilitated this trade, it was beyond the means of a small colony.

General George Washington also recognized the strategic importance for a canal to provide greater security for the American fleet during the Revolutionary War. As ordered by General Washington, a Continental Army Engineer named Thomas Machin investigated the feasibility of a Canal in 1776. He recommended that a canal be built in what is known as the first ever Cape Cod Canal survey.

Several surveys and studies were carried out over the next century. Some of these initiatives began construction, however, none had the required financial or engineering resources to be successful. During the same period, ships continued to wreck along the dangerous outer banks of Cape Cod. In the late 1880s, shipwrecks occurred at the frequency of once every two weeks.

Construction of the Canal

In 1904, financier August Belmont II took a keen interest in the project, and purchased and organized the Boston, Cape Cod, and New York Canal Company. Belmont then partnered with renowned Civil Engineer William Barclay Parsons, who determined that a project to construct a canal would be feasible.

Vintage view of the bridge under construction.

Construction began in 1909, when ships from Maine brought granite rocks that would be used to construct a breakwater at the east end of the canal. At the west end of the canal, dredges were brought in to work on the channel.

Challenges arose throughout this project, including unexpected glacial boulders that were massive in size and unable to be moved by the available men or machinery. As a result, the project decided to utilize innovative solutions like steam shovels and dipper dredges, as well as railroad tracks along the route to allow dump cars to easily carry material way.

The first Bourne Bridge was completed through this project in 1911, and the Sagamore Bridge in 1913. Each bridge consisted of two eighty-foot cantilever spans, was electrically operated, and provided navigational openings of 140 feet. This opening size proved to be a limitation and navigational hazard for vessels given the swift currents in the canal.

Finally, on July 29, 1914, the Cape Cod Canal was opened as a privately operated toll waterway with a parade of ships that included the then Assistant Secretary of the Navy Franklin Delano Roosevelt. With this opening, Belmont achieved his personal objective of opening the Cape Cod Canal before the Panama Canal, which opened seventeen days later.

The canal first opened with a depth of only fifteen feet to receive revenue from ships using the partially completed Canal. The Cape Cod Canal was then officially completed on April 10, 1916.

Early years

Unfortunately, numerous serious accidents within the canal caused lengthy closures and mariners feared the swift currents and narrow bridge openings. The original canal therefore never achieved the level of maritime traffic or revenue envisioned by its investors, and it was a financial failure.

In July 1918, a German submarine fired at an American tugboat off Cape Cod. To ensure safety, President Woodrow Wilson ordered the Federal Railroad Administration to take over and operate the Canal. Belmont resumed operation of the waterway after World War I, but in 1927, sold the canal to the federal government for $11.5 million.

As a result of the Federal Rivers and Harbors Act of 1927, the U.S. Army Corps of Engineers (USACE) assumed control over the canal in 1928. The USACE undertook substantial efforts to improve the operations of the troubled canal, including eliminating tolls and initiating an improvement program. The USACE even distributed a questionnaire to shipping companies to discover why they avoided the canal. Feedback indicated that the movable bridge spans led to serious challenges for ships, as the bridges were kept in the down position, and mariners were forced to battle the swift current in a narrow channel while waiting for the bridges to open.

Construction of the Bridges

Therefore, the USACE began pursuing fixed highway bridges. Fay, Spofford, and Thorndike of Boston were contracted to supervise the design and construction, and the Cram and Ferguson architectural firm provided advice on appearance and architectural details. With a center span of 616 feet and a vertical clearance of 135 feet above mean high water, the bridges were designed to accommodate large ocean-going vessels.

Federal funding during the Great Depression supported these projects which provided hundreds of jobs to skilled and unskilled workers. The bridges were built simultaneously, and were dedicated on June 22, 1935, and then opened to traffic.

The Bridges in service

View of the bridge in 1935 with cars and people traveling over it.

Recognizing the need for further development, the Corps widened and deepened the Canal in the 1930s, making it the widest sea-level canal globally in 1940. These improvements, along with measures such as straightening and lengthening the approach channel, constructing mooring basins, lining both sides with stone to limit erosion, and installing a new navigation lighting system help to increase vessel traffic and cargo tonnage significantly.

During World War II, the Cape Cod Canal became a crucial route for ships looking to avoid the threat of German U-boats patrolling off the coast. The Canal was protected by coastal artillery batteries; however, artillery was never fired in defense of the canal.

In June 1942, the SS Stephen R. Jones ran aground and sank in the canal, forcing shipping to be rerouted around Cape Cod. The SS Alexander Macob was subsequently attacked by a German submarine on July 3, 1942, resulting in the loss of 10 lives. The Stephen R. Jones was then removed with the assistance of 17 tons of dynamite, allowing the canal to reopen on July 31.

The canal continued successful operations for the next several decades. In the early 1980s, the bridges underwent their first major rehabilitations. This work consisted of extensive repairs and replacement of components such as cables, plates, and decking. To carry out this work, each bridge was partially closed for extensive periods, resulting in traffic congestion and delays.

The Canal Bridges today

Today the bridges continue to be owned, operated, and maintained by the USACE. Although they are safe for travel, the nearly 90-year-old bridges are structurally deficient, functionally obsolete, and nearing the end of their usable life. Costs for operations, maintenance, and repair of the bridges also continue to increase as the structures age.

The Sagamore and Bourne bridges are critical to the relationship between Cape Cod and the rest of Massachusetts. They enable vehicular travel, so that individuals and families can access jobs and opportunities, and they provide the only vehicular means for goods and services to come to and from the region. Additionally, the bridges allow tourists and visitors to reach Cape Cod and support the tourism industry which is vital to the Cape Cod economy. In many ways, the bridges allow the Cape Cod that we know today to continue to function.

Moving forward, the bridges must respond to today's needs and expectations, which includes being brought up to modern design standards, improving travel operations and accommodating all modes of travel. These improvements will help strengthen the transportation network and ensure the continued movement of people and goods over the Cape Cod Canal.

Visit the US Army Corps of Engineers New England District Website to read more about the Cape Cod Canal History.

Vintage view of the unfinished bridge from afar.

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