Context of the realisation of this project
	Design and method of operation of the fish ladder
	The multi-species fish ladder
	The eel ladder
	Operation of the fish ladder
	Next steps
	Links to other interesting sites dealing with the copper redhorse and the Saint-Ours dam
	Pictures of the fish ladder

Construction of a fish ladder on the Richelieu River’s Saint-Ours dam

Context of the realisation of this project

	We are dealing with a matter of putting back in place a fish ladder on the Saint-Ours dam because of the fact that, between 1849 and 1967 the dam was not an insurmountable obstacle for the passage of fish. The fish ladder that was there at that time was not replaced when the dam was rebuilt in 1967.
Photo: Parks Canada Aerial view of the old fish ladder operating since 1967. This picture was taken on November 25 1943.

The project of adding a fish ladder on the Saint-Ours dam was put forth in 1996 after various studies by the ministère de l’Environnement et de la Faune du Québec who found that the dam was a major obstacle to the movement of several species of fish that are of concern, such as, the copper redhorse. This fish is one of the 20 species considered a priority with the St. Lawrence Vision 2000 Action Plan (SLV 2000).

Photo: Parks Canada
Aerial view of the dam and the locks at Saint-Ours.

The fish ladder targets five (5) species whose survival is of concern, on the Richelieu River they are the lake sturgeon, the river redhorse, the copper redhorse, the American shad and the American eel. The copper redhorse is the only existing endemic vertebrate species in Quebec. In the spring of 1999, it was officially designated an endangered species in accordance with the Quebec Act, with respect to Threatened or Vulnerable Species. Since 1988, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) also considers this species as threatened.

Since the beginning of Phase III, of SLV 2000, Parks Canada worked at gathering the required funding, in collaboration with its partners, for this important project, which is carried out under the Biodiversity component of SLV 2000 looking into the protection of 35 endangered species of fauna and flora. The fish ladder project is one of the actions mentioned in the intervention plan for the species called: Plan d’intervention pour la survie du chevalier cuivré (Moxostoma hubbsi) 1999-2003, to ensure reproduction in it’s natural habitat particularly in the Chambly Rapids located above the Saint-Ours dam.

Photos : Parks Canada

In July 2000, Parks Canada put out a call for tenders relating to the construction of the fish ladder and work began on September 19. There are nine partners providing project funding, they are:

* Future expenses will be assumed by Parks Canada

Design and method of operation of the fish ladder

In the summer of 1997, a technical advisory committee, made up of biologists and engineers from the departments that are part of SLV2000 departments, first analysed different possible solutions including revising the methods of operating locks for navigation, the implementation of a system to catch and transport fish, as well as, the construction of a fish ladder. This last option came out clearly ahead in respect to its efficiency. The committee then defined the technical characteristics for an ideal fish ladder, which would enable the passage of targeted fish while ensuring that the operation of the structure and the dam be efficient.

Other than the copper redhorse, for which we wish to give access to spawning grounds in the Chambly basin, the restoration of conditions for free upstream passage on the Saint-Ours dam will also enable the improvement of the situation for other species a precarious status, in the St. Lawrence ecosystem, such as, the lake sturgeon, the river redhorse and the American shad. The American eel, a much valued commercial species, formerly highly profitable in the St. Lawrence and Richelieu will, once again, ensure regaining access to Lake Champlain.

Photo : Parks Canada Design of the multi-species fish ladder on the Saint-Ours dam.	Photo : Parks Canada State of construction work in November 2000.

The design of the fish ladder on the Saint-Ours dam took into account requirements and characteristics of each of the targeted species. The main criteria that were considered were:

The migration periods of the targeted species, which are:

	Lake Sturgeon :	May 7 to June 7
	American Shad :	May 15 to June 15
	Copper Redhorse :	June 1 to July 7
	River Redhorse :	du 1er juin au 7 juillet
	American Eel :	June 15 to October 15

the size of the species that varies from eels going upstream (0.2 m) and the maximal size of yellow sturgeons that may go upstream on the Richelieu (2.0);

the fact that the American shad and redhorses cannot bounce;

the size of eels observed at the Saint-Ours dam does not enable them to fight currents over 1 m/sec.;

the change in water levels (tidal range) upstream of the Saint-Ours dam is 0.3 m while downstream is 1.5 m.

the height of the obstacle to climb (upstream, downstream levels) during the summer is about 2.4 m.

experimental fishing carried out under Phase II of SLV2000 showed that no matter what management scenario was considered for the operation of the floodgates of the dam, the fish were more attracted to areas located in the middle or middle-west of the river.

the solution chosen must be permanent and have a low maintenance and repair cost. The solution must enable a follow-up with, a possibility of judging of the efficiency of the structure.

Among several types of existing fish ladders, the single vertically slit ladder was considered to be the best choice for four of the targeted species. As this structure was not appropriate for eels, it was agreed to add an eel ladder. The structure is thus made up of a multi-species fish ladder with single vertical slits for the redhorse, the sturgeon, the shad and, in addition, an eel ladder consisting of an inclined surface next to the fish ladder.

The multi-species fish ladder

This multi-species fish ladder is made up of an entrance basin, sixteen successive basins with vertical slits , as well as, an exit basin. The approximate size of each basin is 3 m by 3.5 m and the difference in levels between them is 150 mm. The bottom level is covered with gravel. Water flows through the structure at a speed of 1 m3/s and the flow used to attract the fish at the entrance is about 5 m3/s. Furthermore, to add a degree of operational flexibility in order to meet with the specific requirements for each species, the fish ladder has two water flow diffusion systems to attract the fish, one from the bottom of the structure and the other from the sides.

Illustration : Parks Canada Scheme of the multi-species fish ladder

An immerged camera has been installed to follow fish and help evaluate the efficiency of the ladder. A viewing window is built into basin no. 2, as well as, an access area for observers. The management plan for the Parks Canada Saint-Ours Canal National Historic Site includes, in the future, observation and interpretation activities that should explain the operation of the fish ladder.

The eel ladder

The concept for the eel ladder was inspired by that of an experimental ladder used by Hydro Quebec at the Chambly dam, upstream of the Saint-Ours dam. A breakwater was fixed on the first pillar of the dam in order to create a zone of calm water where small eels can gather together. A current, which attract them, will then lead them to a 50 degree inclined surface, covered with vertical tubes arranged in a random pattern. At the top, a rain pipe leads the eels to the river.

Photo : Parks Canada Eel ladder at the Hydro-Québec dam in Chambly: more than 10 000 eels used this ladder during its first year of operation in 1997.

Operation of the fish ladder

The construction of the fish ladder and the eel ladder was finished in the Spring of 2001. The fish ladder and the eel ladder are operational since June 2001. The eel ladder will now enable small eels to climb the dam up to mid-October.

Since the fish ladder has been open, about fifteen different species have use it.

Next steps

The inauguration of the Vianney-Legendre Fish Ladder will take place on August 29, 2001 at the Saint-Ours Canal National Historic Site of Canada in the presence of the Minister of Canadian Heritage, the president of the Société de la faune et des parcs du Québec, the president of the Fondation de la faune du Québec and a representative of Projet Rescousse.

Parks Canada is responsible for the implementation of the follow-up program and for monitoring of the efficiency of the ladders on the Saint-Ours dam, and this, in cooperation with Fisheries and Oceans Canada (Fish Habitat Management Division) and the Montérégie regional office of the Société de la faune et des parcs du Québec. Follow-up activities, started in June 2001, will evaluate the efficiency of the ladder with respect to various species. During the first year of operation, all eels will be captured, measured and marked by thermal tattooing and/or with an electronic chip.

Links to other interesting sites dealing with the copper redhorse and the Saint-Ours dam

Biodôme, Conservation programs, Copper Redhorse Environment Canada, Species at risk in Canada Redpath Museum - Quebec Biodiversity Web site - Fishes of Quebec Parks Canada, Saint-Ours Canal National Historic site Parks Canada, Releases BELrive school project (French only) Rescousse, Copper Redhorse Les chevaliers cuivrés passent (Le Devoir — Louis-Gilles Francoeur, in French only)

Pictures of the fish ladder

Work on the construction of a fish ladder on the Saint-Ours dam is just about finished. This photograph of the fish ladder was taken on March 7th 2001.

Photo : Parks Canada Fish ladder in operation, May 14th 2001	Fish observed through a window in the fish ladder

	Viewing window	Eel ladder
Photos : Luce Chamard, Environment Canada June 2001
Photos : Madeleine Papineau, Environment Canada June 2001
Photo: Céline Lachapelle Environnement Canada September 2001