Conservation

Water Quality

Water Quality

The quality of the water flowing through Iowa has been a concern for many years. The change of our landscape from prairie to almost exclusively agriculture and urban areas has degraded our rivers, lakes, and streams through increased pollution and storm water runoff. Ultimately, the pollutants leave our state and travel into the Mississippi River, eventually ending up in the Gulf of Mexico. High nitrate levels are of particular concern in Iowa due to the large amount of land in agriculture. These nitrates we see in our waterways are effecting our local drinking water sources and are directly contributing to the hypoxic zone within the Gulf of Mexico. Nitrates aren’t the only concern, though, high sediment, chlorides, and even bacteria are seen in our streams which can be traced back to both urban and agricultural inputs.

We must act together to address our water quality and each do our part to improve it. At Polk County Conservation we are working to improve the water quality within our parks, as well as guiding others throughout the county to improve the quality of our water. One of the ways we do this is by determining what the quality of water currently is in the county so we can target the areas of highest concern.

Polk County Conservation Water Quality Monitoring Program

Polk County Conservation Board’s mission is to provide the citizens of Polk County with quality outdoor recreation, conservation education, and long term protection of Polk County’s natural heritage.

To accomplish our mission, it is important that we have current and relevant information about the streams that flow within the watersheds of Polk County. As a result, we established the Polk County Conservation Water Quality Monitoring Program (PCCWQMP) in 2015. Support for this program evolved from the passing of the Polk County Water and Land Legacy Bond in 2012.

Polk County Conservation is dedicated to environmental health and recognizes water quality as a fundamental priority in this region. The goal of the water monitoring program is to assess the water quality of watersheds within Polk County. Specific objectives include:

  • establish a baseline for determining stream health based on chemical, physical, habitat and biological parameters
  • assess the health of the local watersheds within Polk County and target areas in need of water quality improvement
  • create partnerships with the public in order to grow our water monitoring program
  • better understand the needs of our watershed system within Polk County

PLAN & PROCEDURE

Twice per month, staff from Polk County Conservation and the cities of Altoona, Ankeny, Des Moines, Johnston, and West Des Moines, and volunteers, trained in monitoring procedures, test 70 sites across Polk County. Field monitors record water transparency and temperature, pH, dissolved oxygen, nitrates/nitrites, chloride, and phosphates. Observations such as weather, stream conditions, water depth, odor and color, and the presence of animals, tile lines and piping are noted.

Regular monitoring will provide baseline data to enable detection in changes to water quality in the future. The data collected will be used to determine overall health of the watershed and identify areas of concern.

With several years of data in place, trends in water quality are emerging. The effectiveness of conservation measures and habitat improvement for any watershed can be evaluated based on the comparison of future data to these emerging trends. Seasonal changes and dramatic weather events such as flooding, drought, and extreme temperatures cause variability in results. The continuation of data collection allows staff to detect changes in water quality and better assess the health of our watersheds. We can then share this information with our watershed and governmental partners to aid in our future efforts.  To view the several years of data already collected, visit the EPA’s website here.

What can you do going forward? Consider becoming a trained volunteer so you can begin to monitor streams or creeks near you.

For more information about the water quality monitoring program, contact Ginny Malcomson at 515-323-5300 or ginny.malcomson@polkcountyiowa.gov.

Polk County Conservation is currently working with Drake University to analyze the data collected through the water quality monitoring program. The outputs from this study will be used to guide decisions on where to target water quality improvement projects. The results will also serve as a starting point when discussing potential management changes within our organization as well as groups throughout the county.

Story Map

Water Monitoring Testing & Studies Timeline & Other Projects

As a citizen of Polk County, you can help us by taking small steps on your own property that will help improve water quality. Check out the links below to learn how:

Water Quality Monitoring Program - Polk County Conservation
Twice per month, staff and volunteers trained in IOWATER monitoring procedures from Polk County Conservation, and the cities of Altoona, Ankeny, Des Moines, Johnston, and West Des Moines test 70 sites across Polk County. Field monitors record water transparency and temperature, pH,  dissolved oxygen, nitrates/nitrites, chloride, and phosphates. Observations such as water odor and color, and the presence of animals, tile lines and piping are noted. Regular monitoring should be able to detect changes to water quality in the future. The data collected will be used to determine overall health of the watershed and identify areas of concern.


Fourmile & Walnut Creek Whole Stream Health Study - Drake University
This three-year study will determine the overall stream health of Fourmile and Walnut Creeks. Monitoring sensors have been placed at three locations along each creek; rural, suburban, and heavily urban. Data will be compared to develop trends and determine ecological stream health
as it moves through each of these vastly different landscapes. The gathered information will be used in the future to determine effectiveness of planned restoration activities.


Multi-Species Monitoring Study - Drake University
This study involves establishing one test area at eight different parks owned and managed by Polk County Conservation. Within each test area, three years of sampling will take place on mammals, birds, butterflies, reptiles, amphibians, dragonflies, and damselflies. Data will be used to determine how restoration activities, surrounding land use, and site disturbances effect wildlife species over time.


E.coli & Turbidity for Public Recreational Safety Testing - University of Iowa IIHR - Hydroscience & Engineering
Through the Greater Des Moines Water Trails Plan, over 85 water access points are planned for waterways throughout the metro. Currently, measuring for E.coli is the method used to determine public safety of a water body for beaches along lakes and ponds. This type of measurement is difficult in running streams and rivers because the E.coli testing takes 24 hours to get results, in which time the water tested has flowed far downstream. In order to gain more instantaneous knowledge, previous studies have shown that it is possible that high turbidity levels (cloudiness of the water) may correlate to high E.coli levels. Unlike direct E.coli testing, turbidity can be measured onsite with instant results. 

 

Potential Health Risk Evaluation from Exposure to Human Pathogens US Department of Agricultural Research - Agricultural Research Service Laboratory for Infectious Diseases
E.coli testing is used most widely when determining whether there is a potential presence of pathogens that may cause illness to humans recreating in our waterways. However, strength of the correlation between E.coli and these pathogens has been shown to vary significantly. This study will test the strength of this relationship, determining if E.coli is really the best indicator of the safety of water for recreating. Along with testing this association, samples will be taken to determine what dangerous pathogens, if any, are within our waterways and where these pathogens may be coming from. This study will complement the turbidity vs E.coli study (above) as part of the Greater Des Moines Water Trails Plan and determine the overall health risk for the public as we implement this plan.

Read the results of the study!


For more information, contact:
Amanda Brown, Conservation Ecologist
amanda.brown@polkcountyiowa.gov