Frequently Asked Questions About Rogue Riverkeeper's Water Quality Monitoring Program
Every summer, Rogue Riverkeeper samples surface water at numerous locations commonly used for water recreation. This year, with the help of a seasonal field technician, volunteers, and partner organizations, we are reporting the water quality sampling results of 20 locations in the Rogue basin through the Swim Guide app and on our webpage. Many people are concerned with water quality where they swim and boat, especially as we get to the end of summer and stream flows get lower. Here are some of the questions we commonly get about the Rogue Riverkeeper water quality monitoring program:
What does Rogue Riverkeeper sample for?
Rogue Riverkeeper samples lake, stream and river water for one thing: one type of bacteria Escherichia coli (the abbreviated name is E. coli). E. coli bacteria live normally in the intestines of healthy people and warm-blooded animals such as birds and mammals. Most types of E. coli are harmless or cause relatively brief diarrhea. A few strains can cause severe illness. Those strains are the ones we hear about in the news, often from food borne sources.
The presence of E. coli indicates fecal contamination from some kind of warm-blooded animal. Fecal contamination is commonly associated with illness. The state of Oregon uses the presence of E. coli as the standard by which the state determines water is safe for human contact. If there is a high presence of E. coli, there are probably other fecally transmitted disease-causing organisms present as well. But the presence of E. coli does not necessarily mean someone will get severely ill from one of the more dangerous strains of E. coli or anything else. But generally the more fecal contamination, the higher the probability of some kind of illness.
There are many other substances in water which can make people sick that Rogue Riverkeeper does not sample and analyze for. Here are a few of them:
chemical contamination
Staphylococcus bacteria which includes MRSA
How do we analyze water for E. coli?
The lighter colored cells in this photo are the ones showing positive presence of E. coli.
Water samples are kept cool and analyzed within 8 hours of collection. Rogue Riverkeeper has a small lab at our office with equipment and supplies to analyze for E. coli. The water sample is mixed with a reagent to grow the bacteria. The sample is incubated for 24 hours at a controlled temperature, then the sample tray is viewed under a black light and the number of fluorescing cells in the sample tray are counted. We use the Quanti-tray system which uses a formula to translate the number of glowing cells into a measurement of E. coli. The resulting number is in units called “most probable number” or “MPN” because bacteria are quite variable and even with testing, there is no hard and fast number for bacteria organisms present.
How do you know if the water is safe to swim in?
The visible appearance, temperature, presence of bubbles, or smell of water do not necessarily indicate whether it is safe or if it meets the standard for water contact safety. Even if water looks cloudy or dark with sediment, that does not mean there are disease causing substances in it. To determine the presence of bacteria and many other substances, one has to sample and analyze the water.
Who else monitors and samples surface water regularly?
As the state agency with the primary responsibility for protecting water quality through the federal Clean Water Act, the OR Dept. of Environmental Quality does regular sampling of surface water in many locations of the state, but very infrequently, with many locations only sampled a few times or once a year. In our region, a small special district, the Rogue Valley Council of Governments, is funded by the cities, counties, and other jurisdictions to sample local streams as part of a requirement to comply with the Clean Water Act. That sampling is performed monthly. One can find data up to June 2021 in their Water Quality Data Library.
Why do some Swim Guide locations fail to meet the standard for water contact?
In Swim Guide we report on a variety of locations from the upper reaches of the Rogue basin at Lost Creek Lake, Emigrant Lake, and the Illinois River, to many small streams that are tributaries connected to the Rogue. No matter where we are sampling, it is the watershed area, that land which is draining water to our sampling location that determines what is in the water. The activities and substances on the land and water upstream of the sampling site can be very different from location to location. Small streams in our region might flow through forests, towns and agricultural areas. Each of these areas and their activities can impact the stream in different ways. Each stream will have different volumes of clean water diluting whatever pollutants may be present.
Here are a few common reasons why a location on Swim Guide may not meet the water contact standard during the summer:
The sampling location is impacted by agricultural activities and irrigation practices and there is little dilution from rain, groundwater, or other contributing streams. This is most likely the cause of high bacteria levels at smaller streams like Little Butte Creek in Eagle Point, Evans Creek in the City of Rogue River, and Wagner Creek in Talent. These streams are used both as a source of agricultural irrigation water and as a means by which to move the irrigation from user to user.
The sampling location is frequented by waterfowl (ducks, geese, etc.). At Baker Park on the Rogue in Grants Pass, there are often large flocks of waterfowl on the shore and in the water. While other locations on the main stem of the Rogue typically have low bacteria presence, this site sometimes has problems with higher levels of bacteria.
What do we do with the data and why does it matter?
Rogue Riverkeeper follows accepted sampling and analysis protocols and submits data to the Dept. of Environmental Quality (DEQ) Volunteer Monitoring Program at the end of the season. This data along with all the other data collected by the DEQ is public information and can be used for anyone looking to understand more about a waterbody in our region. Because bacteria is one of the substances regulated under the Clean Water Act, having quantifiable data from different water bodies helps us know which streams or lakes may not meet the standards set by the Clean Water Act.
How much does it cost Rogue Riverkeeper to sample?
Each sample we take costs almost $9 in materials to analyze and involves driving over 150 miles each week to sample at numerous locations. We raise funds through donations and grants to pay for our monitoring. Your financial support helps our work.
To see where we sample, the last time we sampled, whether a site meets the Oregon standard for water contact go to the Swim Guide app and the Rogue Riverkeeper webpage. Always use your own best judgment when considering safety. If you see pollution and wish to file a complaint with the OR DEQ, use the online complaint form.
SOURCES:
Mayo Clinic page on E. coli
CDC page on Harmful Algal Blooms