Macroinvertebrate Testing


     Ideally, the macroinvertebrate testing sites would match the sites where the physical/chemical testing took place. However, some of those sites were not appropriate for macro testing due to inaccessibility or other factors. Two sites – O’Neil Woods and Granger Road at Crystal Lake – were accessible and appropriate, and were tested.

     The macroinvertebrates that were identified and quantified by the sampling fall into three groups according to their sensitivity to pollution, including silt and sand (sedimentation from water runoff): (1) sensitive; (2) somewhat sensitive; and (3) pollution tolerant. The more diversity of types of macroinvertebrates, especially in the first group (pollution sensitive), the better the water quality. This is quantified by first categorizing the macroinvertebrates by species, then counting the number found in each species. A letter code is assigned according to the count, e.g. A = 1 to 9; B = 10 to 99; and C = 100 or more. However, the number of each type species found in its specific species category is not taken into account in the final overall score for the sampling. That is, it does not matter whether the count was 8 or 88. It is the pollution sensitivity of the species and the number of types found that determine the final score.

     Examples of species in the first group are water penny larvae, mayfly and stonefly nymphs, and caddisfly larvae. In the second group are dragonfly larvae and crayfish. In the third group are aquatic worms, leeches, and certain snails. Each species in the first group are assigned a number score of 3; in the second group, 2; and in the third, 1. Therefore, if 5 different species are found in the pollution sensitive group (Group 1), 5 is multiplied by 3, resulting in an index value of 15. The index values of each of the 3 groups are then added resulting in the Cumulative Index Value, or Stream Quality Assessment: Excellent, Good, Fair or Poor.

     The samplings at O’Neil Woods in 2011 were consistently Poor. In 2012 the samplings rose somewhat to Fair with one Good reading in September. In 2013 the assessments resulted again in the Fair to Poor levels, with a Good result in October (raw score of 20). This is consistent with prior readings at that site which is part of the MetroParks Serving Summit County. Their records also indicate historically low scores beginning approximately in 2006.

     This part of Yellow Creek has very steep slopes, some approaching 90 degrees, and is surrounded by a residential area with impervious surfaces on one side, and a road and wooded area on the other side. Yellow Creek generally is a “flashy” stream as well. As one park employee described this site, the volume and velocity of the stream water at this point can be so high that the macroinvertebrates are literally scrubbed from the stream bed. Our reading in August of 2014 resulted in a Stream Quality Assessment of 15 (Fair), but all of the species collected were in the pollution intolerant category. We also often spot small fish, or darters, at the testing site as well, which may be another indicator of good water quality.

     Also of note are the observations of a person who from 2013 to 2014 consistently fished this area and the public area upstream from our testing site behind the red barn on Bath Road. His fly fishing resulted in the capture and release of the following species: Bluegill, Pumpkinseed, Creekchub, striped shiner, Hornyhead Chub, Striped Shiner, Spotfin Shiner, Bluntnose Minnow, Suckermouth Minnow, Northern Hog Sucker, Common White Sucker, Common Carp (some individuals exceeding 25"), Grass Carp (at least one individual exceeding 35"), Rainbow Trout, Spotted Bass (very rare for this region), Largemouth Bass and Rockbass. Impressive. The last fish species survey was performed by the Ohio EPA at another location in 1996, but they are not due back until 2016, depending on funding.

     There are insufficient data at the site located at Granger and Crystal Lake Roads (Ghent Church) to draw any conclusion, but the readings have ranged from Poor to Good from 2010 to 2013.

      Finally, the fourth location is at Wye Road near the bridge where the North Fork flows into Bath Creek from the north. This location may have better water quality assessments due to the protection of the headwaters in Richfield. In 2012 to 2013 the readings are equally Fair to Good. However, this site is located on private property, and the owner revoked his consent to our use of this location. Easy access is not available nearby.


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Click here for the Summit County Metro Parks assessment instructions.

Aqua Bugs

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