Iowa River Iowa City - US1
Analysis Summary for Series #1419
Benthic Macroinvertebrate Index of Biotic Integrity (BMIBI)
| Metric Name | Value | Score |
|---|---|---|
| MH Total Taxa | 17 | 3.27 |
| SH Total Taxa | 3 | 1.32 |
| MH EPT Taxa | 4 | 1.48 |
| SH EPT Taxa | 1 | 0.68 |
| MH Sensitive Taxa | 0 | 0 |
| SH Ephem % | 0 | 0 |
| SH EPT % | 5.23 | 0.55 |
| SH Chiron % | 79.51 | 2.07 |
| SH Scraper % | 0 | 0 |
| SH Top3Dom % | 100 | 0 |
| SH Dom FFG % | 94.77 | 0.87 |
| MHBI | 6.35 | 2.41 |
| *Mouse-over metric for full name | ||
| **Final IBI is sum of scores multiplied by 0.8333 | ||
Analysis Factors
| Factor | Value |
|---|---|
| BMIBI Type | Warm Water |
| Sample Date | 9/14/2012 |
| Sampling Series | Series #1419 |
| Drainage Area (mi2) | 3158 |
| Log(DA) | 3.49941212567228 |
| Calculation Last Updated | 7/22/2025 3:39:20 PM |
| Sampling Gear | ArtSub |
Sessions used in this analysis
Warm Water
Poor
This reach is always low velocity, especially at low flows. Beginning of bryozoa colonization.
BMIBI Score Explained
This site was analyzed using the BMIBI-Warm Water assessment methodology.
Sites that score between 0 - 30 are considered poor. Severely impaired macroinvertebrate community. Low numbers of taxa present, sensitive species not present, EPT taxa are rare or not present; community extremely unbalanced; dominated by a few pollution tolerant organisms; some trophic functional feeding groups are not represented. Total numbers of organisms may be low. Total taxa richness and EPT taxa richness are noticeably reduced from optimum levels; sensitive species and habitat specialists are rare; EPT taxa no longer dominate the macroinvertebrate community. Taxa that are tolerant of organic enrichment and/or excessive sediment loads are dominant; the community is unbalanced; a few generalist taxa make up a high percentage of the organisms present; collector-gatherers or collector-filterers are very dominant.
This location has been classified as a survey site. Survey sites are compared to reference sites within the same ecoregion. A reference site represents natural stream qualities that are least disturbed by human activities within the watershed. Reference sites are grouped by ecoregion to establish a benchmark against which these survey streams are compared.
EcoRegion Comparison
Scores for a sampling session are compared against reference sites within the same ecoregion:
| Max | 86 |
| 75th Percentile | 70 |
| Median | 62 |
| 25th Percentile | 54 |
| Min | 20 |
| This Session's Score | 11 |
| Total Reference Site Samples | 120 |
| Mean | 61.41 |
| Standard Deviation | 10.8 |