Below, photos and field observations on the Oldman Dam the Oldman River, southwest Alberta
From below="My samples and observations clearly show the massive destruction of the natural ecological river system in the area and the almost complete elimination of the benthic community. There is also growth of unusual masses of algae downstream, and there is a water temperature reduction in the summer. This is the usual type of damage and destruction done by hypolimnion dams. Dams,Research Thermal This is contrary to conclusions of University and Government reports from Alberta." see below.
(See Table 1, about 1/3 from the top of the River at Saskatoon page, for a summary of the effects of Gardiner Dam on the river at Saskatoon. Notice- Zero insects in the benthos at Gardiner Dam outlet.)
In addition to the Bow and Red Deer Rivers in Alberta, Canada, the Oldman River is one of three which join to form the South Saskatchewan River, most of which is in Saskatchewan. The S.Sask. River forms in Alberta. Within a relatively short distance in the area north of Medicine Hat, and south of Oyen, Alberta, waters from the three join and flow past Lemsford Ferry, which I have described as having one of the most unique aquatic communities in the world, especially for Mayflies. See Home,Rare Species, and other pages on this site.
A dam was constructed on the Oldman River in 1992. The impact of dams on river systems in general and this river system in particular has long been known (Thermal Research). In spite of such research on the Saskatchewan River an the damage done by dams, it is reported that:
" the construction of the Oldman River Dam required an environmental assessment impact,----"and this was not conducted at all, by Ralph Klein's government.
"An environmental assessment impact is a neccessity according to the "Navigable Waters Protection Act", where it would be determined if its construction would have any notable environmental impacts on this region. The Friends of the Oldman River strongly felt that the construction of the Oldman River Dam, would severely alter and damage local riparian biomes, wildlife habitat, and aquatic life in down stream from the dam." see: http://www.uleth.ca/vft/Oldman_River/OldmanDam.html
Even more strange than the failure to do an environmental impact study before the dam was built is the fact that a government study was conducted after the construction of the dam, and this Government report concluded that no environmental damage was done.
A study was "conducted by the government, and found the dam to have no significant environmental impact; but the Friends of the Oldman River Society amongst others regard it with much suspect. Again, see:
My samples and observations clearly show the massive destruction of the natural ecological river system in the area and the almost complete elimination of the benthic community. There is also growth of unusual masses of algae downstream, and there is a water temperature reduction in the summer. This is the usual type of damage and destruction done by hypolimnion dams. Dams,Research Thermal This is contrary to conclusions of University and Government reports from Alberta.
Thus the concerns expressed on Environmental Laws Canada seem to be clearly illuminated- lack of meaningful public input or influence, failure to reflect current scientific knowledge and methods, entanglements involving Federal, Provincial, and other interests, etc. etc.
In the past, it seems that the same technique was used in planning to build the Meridian Dam on the South Saskatchewan River- no scientific environmental studies- see Home, but this dam was not built because of economic and political reasons. Lucky for Lemsford Ferry, the South Saskatchewan River, and the environment.
For the present and future, it seems that the same technique of no concern for current and complete science, excessive discretion, etc. is still in play. The planned dam at the river confluence in Saskatchewan has been declared non-damaging to the environment by committees, etc. Too bad for the Main Saskatchewan River in this case. It probably will go ahead as pre-planned. Again, see Home.Home and Environmental Laws.
A small part of the Upstream collection from the Oldman River, north from Hwy 3 on Hwy 22, which crosses the Oldman River. See photo below of Oldman River.
About 10 species are in the photo above, including two species of stoneflies (one not shown),: and a number of Mayflies: e.g. three Ameletus species, Epeorus longimanus, two additional Heptageniid species with 3 caudal filaments, an Ephemerellid (not shown), a Paraleptophlebia species (not shown) and one or more Baetidae.
The Oldman Dam seems to almost completely eliminate the aquatic community at the dam outlet, as is the case for the Gardiner Dam in Saskatchewan.
The water temperature upstream, in the unaltered Oldman and a tributary, was 10 C. At the outlet, water was 6 C, thus leading to the conclusion that the Oldman Dam is of the hypolimnion drain type of construction, issuing water from the cold depths into the downstream river, and thus eliminating most species.
The insects collected a km below the dam outlet. One live stonefly and one live Baetid were collected. To the left and at the bottom of the photo below are specimens flattened but complete. These are intact insects, just distorted but not missing body parts. There are two baetids and one heptageniid. These flat specimens were a mytery until it occured to me that they look as if they had dried completely, and been re-wetted- as sometimes happens in the lab by accident. Thus, I speculate that water flow is completely cut off from the outflow from time to time, and the river bed dries in lagre areas, leading to the dried and subsequently re-wetted specimens. This is speculation at present.
Here, north of Medicine Hat, and south of Oyen, Alberta, the Oldman and Bow Rivers have joined, forming the South Saskatchewan River on the Alberta side near the Saskatchewan border. The area is high Badlands, as can be seen in the photo. Of interest is that the highway crosses a western lobe of the the interesting glacial feathre, the Great Saskatchewan Sandhills, just south of where this picture was taken. The river here is wide with a variety of habitats.
The area would have been destroyed if the Meridian Dam had been built. I am not aware of any ecological samples or studies that are available. See Meridian Dam and past threats near the top of the Home page.
Red Deer River, south of Oyen and north of Medicine Hat, Alberta, near the Saskatchwan border. The floodplain is very wide, surrounding hills are low, and the river is winding with many sand bars. Near here and to the east across the Saskatchewan border, the Red Deer River enters the South Saskatchewan (above) as the final major tributary forming the main So. Sask. River.
For photos of the South Saskatchewan River across the Saskatchewan border to the east, see Lemsford Ferry.Lemsford Ferry
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