Bacteria Monitoring
Frequently Asked Questions about bacteria in the Rivanna Watershed
What do the scores mean?
Bacteria scores reflect the number of E. coli colonies per 100 milliliters of water.
The maximum allowable amount of E. coli bacteria in a single sample of water is 235 colonies per 100 milliliters. This standard is set by the VA Department of Environmental Quality.
High counts of E. coli in a stream indicate that there is an elevated risk of illness from pathogenic organisms.
StreamWatch launched the bacteria monitoring program in July 2012. Our volunteers monitor 13 sites once per month using Coliscan© Easygel. Bacteria levels are one indicator used to determine if water is safe for swimming or other recreation. We monitor fecal bacteria levels, specifically Escherichia coli (E. coli), which are bacteria found in the intestines and fecal matter of warm blooded animals.
See below for a map and table of sites and their monthly bacteria scores.
After collecting 10 – 12 samples at each site, StreamWatch conducts an annual assessment for each site.
Bacteria Monitoring Map
Bacteria data are collected monthly. Click the symbols on the map for site names. Scroll to the table below for monthly sampling results.
Bacteria Monitoring Table – 2015 Monitoring Scores
Click here to see bacteria scores from 2012, 2013, & 2014.
For each site, the bacteria scores are listed by date. When two samples were taken on the same date, both scores are listed. Individual samples that fail the standard set by VA DEQ are highlighted in red.
Flow values
StreamWatch volunteers visually assess stream flow at the time of each bacteria sample. In addition, the US Geological Survey (USGS) provides daily stream flow data online. Two of our local USGS flow gauges are located on the Moormans River at Rt. 601 and on the Rivanna River at Palmyra. Values for both gauges are listed below. Flow values refer to the daily mean discharge, in cubic feet per second.
Precipitation values
StreamWatch obtains daily precipitation values from Weather Underground, which compiles data from local weather stations.
Data
Rivanna River @ Riverview Park – RVN09
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | ICE | normal | ice | ice | 0.03 |
| 4/5/15 | 34 & <34 | normal | 106 | 746 | 0 |
| 5/3/15 | <34 | normal | 103 | 883 | 0 |
| 6/4/15 | 534 | normal | 62 | 457 | 0 |
| 7/2/15 | 67 | normal | 32 | 400 | 0 |
| 7/30/15 | 0 | normal | 40 | 375 | 0 |
| 9/3/15 | 34 | normal | 13 | 73 | 0.22 |
| 10/4/15 | 934 | high | 663 | 5420 | 0.01 |
Rivanna River @ Crofton – RVN10
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | 34 | normal | ice | ice | 0.03 |
| 4/5/15 | 34 | normal | 106 | 746 | 0 |
| 5/3/15 | <34 | high | 103 | 883 | 0 |
| 6/4/15 | 67 | normal | 62 | 457 | 0 |
| 7/2/15 | 67 | normal | 32 | 400 | 0 |
| 7/30/15 | 0 | normal | 40 | 375 | 0 |
| 9/3/15 | 67 | normal | 13 | 73 | 0.22 |
| 10/4/15 | 1034 & 1334 | high | 663 | 5420 | 0.01 |
Moores Creek Upper in Azalea Park – MSV05
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 & <34 | normal | 48 | 376 | 0 |
| 3/1/15 | <34 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | high | 106 | 746 | 0 |
| 5/3/15 | 34 | high | 103 | 883 | 0 |
| 6/7/15 | 67 | normal | 62 | 457 | 0 |
| 7/5/15 | 267 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 67 | normal | 29 | 252 | 0 |
| 9/6/15 | 634 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 100 | high | 663 | 5420 | 0.01 |
Meade Creek @ Meade Park – MDC01
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | ice | normal | ice | ice | 0.03 |
| 4/5/15 | 167 & 167 | normal | 106 | 746 | 0 |
| 5/3/15 | 67 | normal | 103 | 883 | 0 |
| 6/7/15 | 367 | normal | 62 | 457 | 0 |
| 7/5/15 | 767 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 367 | normal | 29 | 252 | 0 |
| 9/6/15 | 167 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 267 | high | 663 | 5420 | 0.01 |
Biscuit Run West of Southern Pkwy – BSC01
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | 34 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | high | 106 | 746 | 0 |
| 5/3/15 | <34 | normal | 103 | 883 | 0 |
| 6/7/15 | 67 | normal | 62 | 457 | 0 |
| 7/5/15 | 67 & 100 | high | 29 | 440 | 0.08 |
| 8/3/15 | <34 | normal | 29 | 252 | 0 |
| 9/6/15 | 67 | low | 8.4 | 83 | 0 |
| 10/4/15 | 100 | high | 663 | 5420 | 0.01 |
Lodge Creek near JPA – XRC03
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | <34 | normal | ice | ice | 0.03 |
| 4/5/15 | 34 | normal | 106 | 746 | 0 |
| 5/3/15 | <34 | normal | 103 | 883 | 0 |
| 6/7/15 | 300 | normal | 62 | 457 | 0 |
| 7/5/15 | 367 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 134 | normal | 29 | 252 | 0 |
| 9/6/15 | 300 & 267 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 100 | high | 663 | 5420 | 0.01 |
Lodge Creek East Tributary – XRC07A
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | 67 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | normal | 106 | 746 | 0 |
| 6/7/15 | 1200 | normal | 62 | 457 | 0 |
| 7/5/15 | 934 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 134 | normal | 29 | 252 | 0 |
| 9/6/15 | 134 & 200 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 100 | high | 663 | 5420 | 0.01 |
Lodge Creek West Tributary – XRC07B
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | 34 | normal | 48 | 376 | 0 |
| 3/1/15 | 34 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | normal | 106 | 746 | 0 |
| 5/3/15 | 34 | normal | 103 | 883 | 0 |
| 6/7/15 | 34 | normal | 62 | 457 | 0 |
| 7/5/15 | 434 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 167 | normal | 29 | 252 | 0 |
| 9/6/15 | 100 & 167 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 34 | high | 663 | 5420 | 0.01 |
Lodge Creek @ 5th St SW – XRC02
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | <34 & <34 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | normal | 106 | 746 | 0 |
| 5/3/15 | <34 | low | 103 | 883 | 0 |
| 6/7/15 | 67 | normal | 62 | 457 | 0 |
| 6/7/15 | 167 | normal | 62 | 457 | 0 |
| 7/5/15 | 500 | low | 29 | 440 | 0.08 |
| 8/3/15 | 67 | normal | 29 | 252 | 0 |
| 9/6/15 | 200 | low | 8.4 | 83 | 0 |
| 10/4/15 | 200 | high | 663 | 5420 | 0.01 |
Rock Creek @ 5th St SW – XMC01
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | normal | 48 | 376 | 0 |
| 3/1/15 | <34 & 67 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | normal | 106 | 746 | 0 |
| 5/3/15 | 100 | low | 103 | 883 | 0 |
| 6/7/15 | 234 | normal | 62 | 457 | 0 |
| 7/5/15 | 200 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 200 | normal | 29 | 252 | 0 |
| 9/6/15 | 100 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 34 | high | 663 | 5420 | 0.01 |
Meadow Creek @ Brandywine Dr. – MWC10
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | <34 | low | 48 | 376 | 0 |
| 3/1/15 | <34 | normal | ice | ice | 0.03 |
| 4/5/15 | 67 | normal | 106 | 746 | 0 |
| 5/3/15 | 134 & 334 | normal | 103 | 883 | 0 |
| 6/7/15 | 134 | normal | 62 | 457 | 0 |
| 7/5/15 | 100 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 167 | normal | 29 | 252 | 0 |
| 9/6/15 | 34 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 234 | high | 663 | 5420 | 0.01 |
Meadow Creek @ Meadowbrook Gardens – MWC11
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | 334 | low | 48 | 376 | 0 |
| 3/1/15 | <34 | normal | ice | ice | 0.03 |
| 4/5/15 | <34 | normal | 106 | 746 | 0 |
| 5/3/15 | 434 | normal | 103 | 883 | 0 |
| 6/7/15 | 134 | normal | 62 | 457 | 0 |
| 7/5/15 | 234 | normal | 29 | 440 | 0.08 |
| 8/3/15 | 200 & 267 | normal | 29 | 252 | 0 |
| 9/6/15 | 900 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 167 | high | 663 | 5420 | 0.01 |
Meadow Creek @ Copeley Rd. – MWC12
| Date | Score (CFU/100mL) | Visual Stream Flow Assessment | USGS Stream Flow, Moormans | USGS Stream Flow, Palmyra | Precipitation |
|---|---|---|---|---|---|
| 2/8/15 | 100 | low | 48 | 376 | 0 |
| 3/1/15 | 34 | normal | ice | ice | 0.03 |
| 4/5/15 | 34 | normal | 106 | 746 | 0 |
| 5/3/15 | 134 | none | 103 | 883 | 0 |
| 6/7/15 | 634 & 634 | normal | 62 | 457 | 0 |
| 7/5/15 | 200 | high | 29 | 440 | 0.08 |
| 8/3/15 | 300 | normal | 29 | 252 | 0 |
| 9/6/15 | 22,667 | normal | 8.4 | 83 | 0 |
| 10/4/15 | 100 | normal | 663 | 5420 | 0.01 |
