Tuesday, July 8, 2014

Seneca Landing Craft Shipyard

During World War II, Chicago Bridge and Iron Co. built the "Prairie Shipyard" in Seneca, IL, to build landing ships. It built 157 of the 1051 LSTs (Landing Ship, Tank) that were built during WW2. 23 of the LSTs participated in the D-Day assault. http://www.navsource.org/archives/10/16/160199.htm has pictures of LST-199 being launched at Seneca and unloading at Normandy.

Landing Ships were designed to have a flat bottom with a shallow draft so that they could get close to land. Thus the 9-foot channel of the Illinois River was adequate for these ships even though they were 327 feet long and weighed 5,500 tons. This freed up the coastal shipyards to build the larger ships such as aircraft carriers, battleships, cruisers and destroyers. Seneca was chosen because only 30 inches of topsoil and creviced limestone had to be removed to get to solid sandstone bedrock that could support the weight of the steel supplies and erected hulls.

The 200 acre site was wedge shaped with three-fourths of a mile along the river. There were 15 berths parallel to the river for erecting ships. As the ships were completed, they were moved to a central way and then prepared for launch. There were 3 Caterpillar tractors to move a ship to the launch way.

Sections were fabricated and hoisted into place to avoid the time and cost of erecting scaffolding. To construct one ship, the hull department welded 23,300 pieces totaling 1,340 tons of steel (Colby). Most jobs began with a two-week training period, but welders were trained for four to six weeks. Chicago Bridge and Iron Company was chosen as the contractor because of their welding experience manufacturing their primary product---pressurized tanks of various types and shapes. Many a town had a water tower which had been constructed by CBI. Teams moved from ship to ship doing the same work on each one. It required 880,000 man hours (actually, probably some women hours) to construct the first ship which was launched Dec. 13, 1942. The last ship was built with 280,000 person hours.

39 gallons of champagne were used to launch the 157 ships. The initial plan was to launch a ship each week, but CBI achieved a launch rate of 7 per month. Because they were launching into a river, the ships slid in sideways. They hit the water at a speed of 22 to 28 mph. Observers on the south bank were frequently drenched by the wave of water traveling from the river across the fields. The ships were launched with the radar mast laid flat on the deck. When they got to New Orleans, the mast was raised again and the radar equipment was installed.

My road atlas indicates the current population of Seneca is 2,371. The population at the beginning of the war was 1,200. During the war, about 27,000 people worked at the shipyard. The peak employment was 11,000. And some of those workers had kids. So the population of Seneca was an order of magnitude more than it is today. The Chicago Tribune has a big article on the shipyard by Ted Gregory on page 12 of the Main section of their June 8, 2014, issue. The article includes the recollections of the native Sandra Timmons on the impact of the population growth on the town.

By May, 1946, the shipyard had been silent for almost a year and structures were being torn down. But the town kept the waterworks, sewage disposal system, better streets, fire protection equipment, and a new school building that the Navy built.

The town has built a monument to the men and women who built the LSTs and who served on them.

The pictures from the main source I used for the shipyard info.
Omaha Beach
Loading Supplies
Unloading Supplies
Steve OConnor provided several comments concerning the impact on the population of Seneca in his posting concerning Illinois's contribution to the WWII war production. Of particular interest are thse pictures.

Steve OConnor comment on his posting
Steve OConnor comment on his posting
The Seneca shipyard had 15 births where 15 ships would be at different stages of construction. As each ship was finished it would be slid to the center rails where it could be pushed to the Illinois River and launched sideways. This site was chosen because the ground has a foundation of sandstone strong enough to support the weight of the ships without pilings having to be sunk.
From the above picture, I was also able to access:
From Steve OConnor
From Steve OConnor


  1. This is the only photograph I have found of the shipyard. https://www.facebook.com/photo.php?fbid=398260660262192&set=a.265205283567731.68048.100002347842957&type=3&theater


    This book is an account of what happened to the people and the institutions of a small American town as it went through an industrial boom during World War II.

    Seneca, Illinois had a population of 1,235 in 1942; and a population of 6,600 two years later. The boom was due to the location of a shipyard on the bank of the Illinois River next to the village. One hundred and fifty-seven ocean-going LST (Landing Ship Tank) ships were built in Seneca and floated down the Illinois and Mississippi rivers to the sea. To care for the inrush of workers, public housing projects were built, churches, and schools expanded, and the whole institutional complex of the village was transformed. Six million dollars of government money was used to expand the facilities of the community. Another six million dollars was spent to equip a shipyard. Eighty-two million dollars was paid in wages to Seneca shipbuilders in a little less than three years....

    A boom town in wartime is different from a boom town in peacetime. Boom towns in peacetime know congestion and like it, because the remedy is set in motion by the boom itself. Private capital is attracted by the opportunity to invest in a rapid growing town that expects to hold its growth permanently. Public bond issues are readily approved with the expectation of repaying the debt out of increased tax income. But the boom town in wartime cannot attract private capital. Neither are communities willing to take on, at their own expense, the expansion of school, water, sewer, and business facilities for a population that is bound to be temporary. It is one thing to build or to expand a factory for production; the cost of the expansion can be included in the charge made for the product. It is quite another thing to increase the capacity of the community to serve the needs of the new manpower drawn to the factory.

    Robert J. Havighurst and H. Gerthon Morgan
    The Social History of a War-Boom Community, 1951
    from the introduction p. xi-xiii

    "The figure of five thousand itself was generally thought to be an overestimate of the need for workers in the shipyard. Privately, government officials and others who were in a position to make an informed guess said that the number of employees might go to thirty-five hundred.

    But everybody was underestimating. Eight months after shipbuilding began the employment total reached nine thousand. The number fluctuated about this figure for a year, and then rose to a maximum of 10,600 in the summer (June) of 1944. (the D-Day buildup - Steve) With this labor force, the yard launched a ship every four days during a peak production period of fourteen months.

    Robert J. Havighurst and H. Gerthon Morgan
    The Social History of a War-Boom Community, 1951
    p. 47


    If men were to build ships in Seneca, they would have to have houses for their families. They would not stay long on the job if their children were clamorous and their wives were dissatisfied. Thus the provision of tolerable housing conditions had high priority over other matters.

    All the existing housing facilities were filled to overflowing in an area thirty-five miles surrounding Seneca. All vacant dwellings were filled up in the neighboring cities of Ottawa, LaSalle, Streator, Marseilles, Morris, Peru, Spring Valley, and Oglesby. Trailers appeared in back yards and in vacant lots in Seneca. Single houses were remodeled into multiple dwellings, and spare rooms were rented in all the surrounding towns. But after all available living space was occupied, still more was needed.

    The need for new housing could not be met by private business. The practical certainty that shipbuilding in Seneca would be stopped after the war, together with wartime prices and restrictions on building materials, made the investment of private capital in new housing a hazardous if not impossible matter, and the only alternative was public housing.

    The Federal Public Housing Authority was called on to supply the needed. The FPHA built, in total, 1,467 family units and a dormitory for 300 men. (1)

    1. The FPHA also built projects in Ottawa, the county seat, for Seneca shipyard workers.

    Robert J. Havighurst and H. Gerthon Morgan
    The Social History of a War-Boom Community, 1951
    p. 61


    War homes began to disintegrate under the crowbars of a dismantling crew. Only sixty-seven apartments were left, to be used by war veterans who wanted housing and who were willing to live in Seneca and commute to work in surrounding towns....

    Not more than five or six shipyard families remained in Seneca; but another forty families moved into town during the years after the war.

    Robert J. Havighurst and H. Gerthon Morgan
    The Social History of a War-Boom Community, 1951
    p. 325-330

  4. "The problem of Negro housing became increasingly acute in certain Illinois towns during the war (WW II); other communities avoided it by excluding the Negro. There is, for example, the case of the Seneca shipyards. At a conference sponsored by the state Department of Public welfare the question of placing Negro workers in the shipyards was raised. The mayor of Ottawa, where a large part of the workers resided, reminded the group that his city had a restriction on the number of Negroes admitted to residence. Out of a population of more than 16,000 there were 107 Negroes, and no Negroes resided in Seneca. The personnel director at the shipyard then related his experience: he had hired a total of 19,000 persons, had talked with 40 Negroes, hired 38. Not one of them finished a day's work. “We have shown no discrimination,” he declared,”but they decided not to work here.”....

    Chicago, of course, contained the problem in its largest proportions. An estimated 80 per cent of the city's residential area was closed to Negroes by restrictive covenants."

    Mary Watters
    Illinois In The Second World War - Volume II: The Production Front, Copyrite 1952, Illinois State Historical Library
    p. 310-312