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The White Cloud site on the Blue River is located near Corydon, Indiana. It is off of Highway 62 in Harrison County at the end of Harrison Spring Road where a bridge previously connected this area with the small town of White Cloud.
White Cloud is located in the Eastern Deciduous Biome and the unglaciated, steep sloped Escarpment Section of the Shawnee Hills Natural Region. The main soil type along the stream is the Corydon Stony Silt Loam, with the banks exhibiting evidence of soil erosion. The bedrock is composed of rocks primarily Middle and Upper Mississippian in age.
The area is the site of an old mill dam that is partly intact. Over time, the mill pool above the dam has silted in, and the upper pool water level was judged to be lower because the middle of the dam has been carved out so that canoes do not have to portage over the dam. As with the Stage Stop Campground site, the water has been redirected through a narrow area. Unlike Stage Stop, however, the alteration occurred several years ago when canoeing was becoming popular in this stream. This is also a historic area for fishes. It is the site where the first spotted darters were collected in the Blue River system. At that time (roughly 20 years ago) the iron bridge was still present, and the dam was mostly undisturbed.
This site was evaluated on October 5, 1999 at 1:25 P.M. EDT. The weather was sunny and breezy with an air temperature of 63 F and relatively low humidity. The river discharge had been extremely low in the months proceeding the study due to an extended drought period in the area. At the time of the study, however, the rate of discharge was only slightly lower than the normal amount for this time of year. The water temp at the site was 59 F. The west bank at this location was steep and rocky making accessibility from this bank difficult. The east bank was moderately steep and not quite as high as the western bank.
Riparian features here included about 80% coverage, including some 8 sycamores and 5 silver maples in the study area. Considerable vines and shrubs were noted on the banks in this area. The vegetational cover was judged to be excellent. Instream cover was considerable with boulders, water willows, logs, leaves and 3 actual and 2 potential root wads present. Water willow and duckweed were abundant along the edge of the river. The algae maps were thicker here at the time of this study than had been noted in any previous study done here.
The manmade riffle through the dam was 15 ft. wide and twenty yards in length. It had an average depth of 9 inches, and a maximum depth of 17 in. The average velocity was 6 ft. per second. The discharge was 75 cubic ft. per second. Further water testing indicated a slightly alkaline pH of 7.5. While dissolved oxygen levels were only 4 mg/L at the top of the test riffle, levels were 7 mg/L at the bottom of the riffle. Nitrate levels were at .6mg/L and E. coli levels were found in the amount of 230 colonies per 100 milliliters using fecal coliform testing.
The riffle substrate consisted of small rocks, flattened rocks and cobble weathered by the stream, large gravel and larger embedded boulders. Most rocks were extracted from the dam when the canoe chute was constructed. There was also a smaller riffle to the right side of the test riffle (facing downstream) that had a bed consisting of sand and small gravel. A majority of the rocks in this area were covered with algae. Large algae mats were noted near the banks of the stream near the test riffle as well. In the gravel outwash community, driftwood and logs were lodged against the trees as a result of previous flooding here in the past. The floodplains were mainly agricultural with typical corn and soybean fields dominating them.
Triangular kick net samples of the macro-invertebrates in the riffle produced stonefly nymphs, caddis fly larvae, aquatic worms, mayfly nymphs, right-handed snails and Asiatic clams. The PTI water quality rating of 20 indicated that the stream quality at this site was good.
Fish samples included banded sculpin, spotted darters, stonerollers, and greenside darters. One of the greenside darters collected was perhaps the largest collected during the study. A rather large male spotted darter was also collected in the riffle.