Question: Was Duluth Ship Canal or Cross Florida Barge Canal cancelled for environmental reasons?

Context articles: Erie Canal Lock 52 Complex
Duluth South Breakwater Inner Light
Duluth Ship Canal
Ship canal
Cross Florida Barge Canal
Droitwich Canal
Canaveral Barge Canal
New York State Department of Public Works
Duluth North Pier Light
Duluth South Breakwater Outer Light

Erie Canal Lock 52 Complex is a national historic district located at Port Byron and Mentz in Cayuga County, New York.
 The district includes two contributing buildings (the Erie House and the blacksmith shop / mule barn); three contributing engineering structures (Erie Canal Lock 52, culvert, and canal prism of the enlarged Erie Canal); and archaeological sites associated with the canal operations.
 Lock 52 was constructed 1849-1853 as part of the Enlarged Erie Canal program.
 It remained in operation until the rerouting of the canal under the New York State Barge Canal System in 1917.
 The Erie House was built in 1894 and is a two story frame structure that housed a saloon and hotel.
The Duluth South Breakwater Inner Light is a lighthouse on the south breakwater of the Duluth Ship Canal in Duluth, Minnesota, United States.
 It forms a range with the Duluth South Breakwater Outer Light to guide ships into the canal from Lake Superior.
The Duluth Ship Canal is an artificial channel cut through Minnesota Point, providing direct access to Duluth harbor from Lake Superior.
 Begun privately in 1871, it was put under federal supervision and maintenance several years later.
 It is still an important component of the harbor facilities.
A ship canal is a canal especially intended to accommodate ships used on the oceans, seas or lakes to which it is connected, as opposed to a barge canal intended to carry barges and other vessels specifically designed for river and/or canal navigation.
 Because of the constraints of accommodating vessels capable of navigating large bodies of open water, a ship canal typically offers deeper water and higher bridge clearances than a barge canal of similar vessel length and width constraints.
The Cross Florida Barge Canal, now officially the Marjorie Harris Carr Cross Florida Greenway is a protected green belt corridor, one mile (1.6 km) wide in most places.
 It is named for the leader of opposition to the Cross Florida Barge Canal, a canal project to connect the Gulf of Mexico and the Atlantic Ocean across Florida for barge traffic.
 Two sections were built but the project was cancelled, mainly for environmental reasons.
The Droitwich Canal is a synthesis of two canals in Worcestershire, England; the Droitwich Barge Canal and the Droitwich Junction Canal.
 The Barge Canal is a broad canal which opened in 1771 linking Droitwich Spa to the River Severn at Hawford Mill, Claines.
 The Droitwich Junction Canal is a narrow canal, opened in 1854, which linked Droitwich to the Worcester and Birmingham Canal.
 Both were built to carry salt, and were abandoned in 1939.
 They have been the subject of a restoration plan since 1973, and the Barge Canal was officially reopened in 2010, while the Junction Canal reopened in July 2011.
 Following the opening of the canal, ownership transferred to the newly created Canal and River Trust
The Canaveral Barge Canal provides an east-to-west link between the Atlantic Ocean and Indian River Lagoon across northern Merritt Island, Florida, in two segments separated by the Banana River.
 It is located 15 miles south of Titusville, Florida.
 The canal is 12 feet deep and has entrances to other water systems including Syke's Creek and various marinas.
 The canal links Port Canaveral along the Atlantic Ocean to the Intracoastal Waterway running down the center of the Indian River Lagoon.
 The canal was constructed to allow the transport of crude oil by barge to the two power plants south of Titusville, Florida.
The office of Superintendent of Public Works was created by an 1876 amendment to the New York State Constitution.
 It abolished the canal commissioners and established that the Department of Public Works execute all laws relating to canal maintenance and navigation except for those functions performed by the New York State Engineer and Surveyor who continued to prepare maps, plans and estimates for canal construction and improvement.
 The Canal Board (now consisting of the Superintendent of Public Works, the State Engineer and Surveyor, and the Commissioners of the Canal Fund) continued to handle hiring of employees and other personnel matters.
 The Barge Canal Law of 1903 (Chapter 147) directed the Canal Board to oversee the enlargement of and improvements to the Erie Canal, the Champlain Canal and the Oswego Canal.
 In 1967, the Department of Public Works was merged with other departments into the new New York State Department of Transportation.
The Duluth North Pier Light is a lighthouse on the north breakwater at the entrance to the Duluth Ship Canal.
The Duluth South Breakwater Outer Light is a lighthouse at the end of the south breakwater of the Duluth Ship Canal.
 It forms a range with the Duluth South Breakwater Inner Light.