Fathead minnows used in testing are easy to maintain in a tank
Aquatic Toxicity Testing
A vast majority of our work is performing whole effluent toxicity testing (WET Tests) for wastewater treatment plants and other point-source elimination systems. The state of Indiana and the EPA (Environmental Protection Agency) require all point-source elimination meet specific standards of toxicity before the effluent can be safely discharged into a stream, river, or other waterbody. Our lab uses toxicity testing to accomplish this under EPA method EPA-821-R-02-013. Click on EPA Methodsto learn more. The results from toxicity testing provide data to not only determine if a discharger is in compliance, but also helps regulators make decisions on NPDES permit requirements.
When performing a toxicity test, there are two main species that are used and include the water flea (Ceriodaphnia dubia) and the fathead minnow (Pimephales promelas). Sometimes the green algae species Selenastrum capricornutum is also used. First, the wastewater (or effluent), is collected as a composite sample at the plant from an outfall. Second, six series of dilutions are made with the effluent including a control. Lastly, the test animals are added to each dilution (with replicates). Factors such as survival and growth (minnows) and survival and reproduction (water fleas) are measured over a seven day period (chronic testing). These animals can be quite sensitive to many contaminants in the water and are easily reared in the laboratory. Any negative effects of the effluent can be seen through reduced survival, growth, and reproductive rates.
Sometimes only acute testing is needed for a NPDES permit which typically last 48-96 hours. Along with the water flea and fathead minnow, a third species is sometimes used known as Daphnia magna or the giant water flea.
Water flea under a microscope
Lake and Stream Surveys/Watershed Diagnostic Studies
Our work is not only confined to the laboratory, we also specialize in performing various waterbody surveys and diagnostics of watersheds. Observing the quality of our waters sometimes requires being out there in direct contact with the environment. It is important to monitor the health and integrity of waterbodies as our landscape continues to change and can be measured by the abundance and diversity of aquatic communities. Fish, mussels, and macroinvertebrates are the most commonly used indicators of water quality. Watershed management, restoration practices, and lake and river enhancement are also used to enhance and restore water quality. We can then use this information to help our clients make better decisions and suggest Best Management Practices (BMP's) to address issues with water quality.
Some of the methods or measurements we can perform include:
Fish, mussel, and macroinvertebrate sampling
Qualitative Habitat Evaluation (QHEI)
Measuring parameters such as dissolved oxygen, pH, ammonia, chlorine, phosphorus, nitrates, and many other water quality parameters
Combined sewer overflow monitoring
Toxicity reduction evaluations
Observing a small pool for aquatic insects
Example of a soils map of the Sugar Creek Watershed in Boone and Clinton counties, IN
Geographic Information Systems (GIS)
There is a growing need to more effectively manage biological data, as over time this can accumulate as continuous monitoring is performed on waterbodies. GIS provides a great solution to this problem. Sometimes, it is beneficial for watershed projects to visualize and/or model trends in water quality or many other types of information related to the area of interest. That is where map making comes in. In order to make predictions or implement restoration/management of a watershed, it is always a good idea to incorporate the data a GIS can provide.
Watersheds can not only benefit from GIS, but municipalities and industries can too. It might be helpful to locate and monitor all CSO's or MS 4 and other elimination sites. If any construction in or within the vicinity of a waterway is planned, then finding out how to reduce sediment loads may make the process run more smoothly. A farmer may also want to know how to reduce nutrient inputs into a stream. A GIS can solve these issues and we can help!
We are just beginning to realize the potential a GIS can give many projects. We recently completed a watershed diagnostic of the Sugar Creek watershed. GIS was used various times for this project to gain a better understanding of the nature and properties of the watershed. A soil map depicting the soil complexes found within the watershed (shown left) was used to locate areas in the watershed that contain soils suitable for wetland and prairie restoration. Maps of land use, erodible and hydric soils, wetlands and floodplains, and locations of confined feeding operations were just some of the maps used to help identify areas in the watershed that may be degraded. For more information on this project, please click on the link below.
You can also download a shapefile of our study sites for this project that contains information about location and some water quality parameters measured at each location. Creating shapefiles and feature classes so that they may be viewed in ArcDesktop or ArcExplorer is another service we can provide for your data. *ArcExplorer is a free program that can be downloaded here: ArcExplorer Free GIS for all
Pathogens in Biolsolids
Biosolids are a by-product of the treatment process at wastewater treatment facilities. Most of the time this material is either put into a landfill or is incinerated. If the WWTP decides to recycle the biosolids for land application as a fertilizer, it must be tested for pathogens to ensure safety to humans and the environment. E. coli, Salmonella, enteric viruses, helminth ova, and many other human pathogens can be detected and measured to meet federal standards before use.