South Skunk River Cleanup – Spring 2024

by Dan Haug | Apr 24, 2024

16 people participated in the cleanup (2 not pictured, photo credit: Jake Moore)

On April 20, volunteers cleaned up trash along a 3.5 mile stretch of the South Skunk River in Ames, from River Valley Park to S. 16th St. Several people also ventured up Ioway Creek, and those who stayed on shore had plenty to do. The fast current meant we arrived at the destination earlier than expected, where we set to work clearing out an abandoned campsite. Judging by some of the items we found, families with children had stayed there, so please support organizations that work on affordable housing and provide emergency assistance. In between stops at sandbars to retrieve trash, there was ample opportunity to enjoy the river. The fast current made for a fun ride through some mini-rapids (nobody tipped!), and we saw kingfishers, great blue heron, and a bald eagle.

Volunteers launched canoes at N. River Valley Park in Ames (credit: Liz Calhoun)

Chilly weather (high of 48 degrees) may have dampened some of the initial enthusiasm for our spring 2024 creek cleanup event. We went from having not enough canoes for everyone who registered, to several extra canoes. With a smaller flotilla than last spring, we can’t claim a record breaking haul, but we did remove more more trash per person! In addition to the usual cans, bottles, plastic and styrofoam, finds included four tires, seven empty propane tanks, a shopping cart and a microwave.

April 2023: 3,020 pounds/40 people = 76 pounds/person
April 2024: 2,100 pounds/16 people = 131 pounds/person

Tony Geerts likely exceeded that average figure, arriving at the take out point with a big tractor tire. It would have made a great picture, but as I was rushing up to capture the moment, my phone slipped out of my hands and into the river! Fortunately, other people took photos and have shared them with me.

Volunteers with 2500 trash removed from South Skunk River

Assembling the tools, canoes, food, and people was a collaborative effort involving Prairie Rivers of Iowa, the City of Ames, Story County Conservation, the Skunk River Paddlers, and the Outdoor Alliance of Story County. Thank you to all who volunteered, organized, and supported the event.

Water quality results for 2023 in Story County

by Dan Haug | Apr 15, 2024

Our 2023 Annual Report is now available with results of both volunteer and lab testing of water quality in lakes and streams in Story County. The 56-page report can be navigating by clicking on headings in the table of contents or by using the “Bookmarks” feature in your PDF reader. Below are some of the key findings.

Amelia Whitener leads a water monitoring demonstration at a trash cleanup event.

The volunteer program continues to grow and improve in consistency.

49 volunteers entered 969 data sheets into the Clean Water Hub this season.
Many volunteers are monitoring their assigned site biweekly, with 20 sites sampled at least 20 times.

Mayfly larvae (nymph) under magnifying glass

This was a challenging year for fish and aquatic insects.

In addition to many creeks drying up, volunteers observed dissolved oxygen drop to low levels at 53% of stream sites.
Biological surveys showed mixed results, with some streams scoring poorly but sensitive insects like mayflies present in others.

Cows with access to creeks are one possible source of E. coli bacteria

E. coli bacteria levels in streams remained high.

All thirteen streams with enough data to evaluate this season exceeded the primary contact recreation standard. Three streams exceeded the secondary contact recreation standard: (West Indian Creek, College Creek, and Ballard Creek.
However, over the last four years, most sites on the South Skunk River meet the standard when there is enough water to float a canoe.

UV disinfection system at Ames Water Pollution Control Facility

Wastewater treatment plants are not yet capable of removing some of the pollutants we monitor, and can have a large influence during drought when effluent is less diluted.

Effluent from the old sewage treatment plant in Nevada was found to be a major source of E. coli bacteria. The new plant, currently under construction, includes a disinfection system that should address the problem.
Stream sites downstream of sewage treatment plants tend to have elevated chloride and phosphate.

The encouraging trends we noted in the 2022 report held up with another year of data. Water quality trends are often driven by weather, but we pulled out subsets based on streamflow to remove some of this influence.

E. coli in the South Skunk River below the Ames Water Pollution Control Facility has improved relative to the pre-2014 baseline period, especially during dry conditions when wastewater has the greatest influence.
Nitrate in the South Skunk River below the confluence with Ioway Creek improved relative to the pre-2014 baseline period, even after excluding dry periods. This pattern is consistent with improvement from conservation practices.

Paddling While Impaired

by Dan Haug | Mar 16, 2024

For safety’s sake, I wish people would not mix boats and alcohol, but I’m writing about the other type of impairment that can get in way of having a fun and safe experience on Iowa’s lakes and rivers: water quality. Every two years, the Iowa Department of Natural Resources takes stock of which lakes and rivers have water quality good enough to fully support recreation, fishing, drinking water supply, and other beneficial uses. Those that don’t go on the Impaired Waters List. The draft 2024 Impaired Waters List has been published and you can make public comment through April 12.

Understanding the numbers

Most of the op-eds and news stories about the impaired waters list focus on the numbers. There are 572 rivers and streams, 137 lakes, and 12 wetlands on the impaired list. If you had forgotten that Iowa has water quality problems, here’s your biennial reminder!

This year, there are fewer impaired waters than in the 2022 cycle. Much will be made of that, and will be much ado about nothing. The Impaired Waters List is not very useful for evaluating water quality trends, because the number of waters assessed and the methodology used to assess them is always changing. It’s also worth noting that the assessment period (2020-2022) included long stretches of drought, which means less runoff, so it’s possible that some of the 97 waters removed from the list will go back on the impaired list when we get some wetter weather.

Missing data

Not too long ago, the biggest category in the integrated report was waters not assessed. This year, it has dropped to 49% of rivers, 44% of lakes, and 21% of wetlands. We can claim a little bit of credit for this. Eight stream segments formerly in the not assessed category were tested for E. coli as part of the Story County water monitoring program and are now in a category called Waters in Need of Further Investigation (WINOFI). There’s a state law that prevents IDNR from using third-party data for regulatory decisions, but I still appreciate that they reached out and included our data in the report!

An example of Waters in Need of Further Investigation (WINOFI)

Seasonal E. coli averages for West Indian Creek, from our local monitoring program.

Finding clean waters

I’m most interested in which waters are impaired and why. For rivers, the leading cause of impairment is E. coli bacteria, an indicator of fecal contamination and a proxy for other pathogens that could potentially make people sick if they swallow some water while recreating.

I am sometimes asked where to go in Iowa to find clean water for paddling, swimming, floating in an inner tube, or just letting the kids splash and catch crayfish in the creek. A map or list of impaired waters is not very helpful for this, because the waters that aren’t included might be clean, or they might not have been assessed. So I made an interactive map, color-coded to show which lakes and rivers met or exceeded the primary and secondary contact recreation standards, in the last four recreational seasons. Hopefully this a just a prototype for something even better and more comprehensive.

Improving Impaired Waters

We don’t want to just avoid the impaired waters, we want to know how to clean them up. The Impaired Waters List is also a waiting list for a water quality improvement plan, or Total Maximum Daily Load (TMDL). IDNR has studied swimming beaches at several lakes (including Hickory Grove Lake in Story County), and found that E. coli is highest in the wet sand at the beach, and lower in the lake and tributaries. For these lakes, that suggests that the biggest sources of contamination are located at the beach, things like geese and diaper malfunctions. For rivers impaired by E. coli, we don’t know the cause. Many rivers have been waiting decades for a TMDL in a low priority tier, and a TMDL that was written in 2017 for the Iowa River seemed incomplete.

However, after attending the Raccoon River Watershed Association’s annual conference on March 9, I no longer feel like Iowa has given up on recreational water quality in rivers. Robin Fortney shared reminiscences of many river trips. Jon Wenck (IDNR) and Pat Boddy (ICON) talked about Iowa’s growing network of water trails. It’s clear there are people who care about our rivers and see how they can benefit quality of life and economic development. Claire Hruby (Drake University) shared some early results from microbial source tracking and microbial risk assessment research in Polk County. With these approaches, can find out which pathogens are present in the water (not as many as we feared) and whether waste is coming from livestock, wildlife, or humans or a combination!

My contribution to the conference was a nuanced look at exactly how CAFOs (big feedlots) impact water quality. I hope to share a video of the presentation and a report in our April newsletter. There are far too many spills and leaking manure storage structures, and manure management plans don’t prevent over-application of nitrogen and phosphorus. However, the claim that waste from factory farms is responsible for most of Iowa’s impaired waters is just not supported by the data. Here is one figure from my presentation. Notice that Iowa has many rivers with extremely high E. coli levels but fairly low livestock densities in the watershed. To understand E. coli contamination, you have to consider not just the amount of feces produced, but how it likely it is that feces will reach the water before the bacteria die off.

Graph of E. coli vs livestock density in 58 Iowa watersheds

The Fine Print

If you explore the Impaired Waters List and the rest of the assessment database, you will likely run across some things that don’t make sense. I share your frustration! This pair of short videos from our “Clean Water Act: 50 Years, 50 Facts” series contrasts how Section 305(b) and 303(d) of the Clean Water Act should work in theory, and how it can go wrong in practice. However, I continue to see improvements in the assessment database (ADBNet) and water quality database (AQuIA) and want to express my appreciation to IDNR for the data they collect and their efforts to be make it available to the public.

Green Stuff in the Skunk River

by Dan Haug | Mar 14, 2024

On Tuesday, March 12, residents on the north edge of Ames noticed that the South Skunk River was cloudy and had turned an unusual shade of bluish green. By the time I looked at it on the afternoon of March 13, the color had faded and the water was less cloudy, but it still had a soupy, streaked appearance that I’ve seen before in lakes following a toxic algae bloom. I’m gonna go out on a limb here and say it’s blue-green algae (cyanobacteria).

Cyanobacteria bloom in the South Skunk River

Cyanobacteria bloom, showing paint-like streaks.

“Algae” is a word that gets lazily applied to any living thing that does photosynthesis but that isn’t a plant: from tiny glittering diatoms in a drop of pond water to giant kelp in the oceans. The other kind that I noticed in the South Skunk River this week is filamentous green algae, which forms slimy hair-like strands on rocks and globs on the water’s surface. Color is the least of the differences.

Cyanobacteria are tiny and simple. There’s strong evidence that the chloroplasts in the cells of plants and green algae are the captured descendants of cyanobacteria. This amazing phenonemon is called endosymbiosis, and it’s happened multiple times in the history of life on earth. If you’ve never heard of it, I’d recommend this YouTube video, which explains the concept with cartoons.

The practical reason to know if the green stuff in the water is cyanobacteria is because they can produce toxins. I wasn’t able to get a sample tested for microcystin (and chances are, this algae bloom will have dispersed by the time you read this), but I would recommend keeping your dog out of water that looks like paint or pea soup, to be on the safe side.

Green algae in the South Skunk River (Rick Dietz)

A simple guide for green stuff in the water.

Why is the water so green, so early? Algae growth is limited by the availability of light, heat, and fertilizer–phosphorus in freshwater, and to a lesser extent nitrogen. We’re getting unseasonably warm weather before there’s any leaves on the trees to shade the water. As for the fertilizer, I’m not sure where it came from, or when. Rick Dietz and I tested nitrate and phosphate with field kits on Wednesday and measured 0 mg/L. Nitrate and phosphorus levels were also fairly low at this site when we collect grab samples in February. Maybe something was washed into the river earlier in the week, but it has since been used up by the algae or has washed downstream. I’ll amend this article if I find out something conclusive.

Metrics from the 2023 monitoring season

by Dan Haug | Feb 8, 2024

Monitoring a stream once or twice a month is a big commitment, but our locally-led water monitoring program (which started in Story County but has expanded to Hamilton County) has no shortage of committed volunteers! The following metrics show the continued growth of the program in size and consistency.

Also, let’s give a shoutout to the people who work behind the scenes to make it happen! Sara Carmichael of Story County Conservation keeps everyone on track and equipped with supplies. Heather Wilson of the Izaak Walton League of America helps train volunteers and has been leading up the new Nitrate Watch initiative. We rely on the IWLA’s Save Our Streams program for training materials and the Clean Water Hub for data entry. In addition to volunteer monitoring, Maryann Ryan and her team at the City of Ames Laboratory Services Division process weekly samples from 3 sites and monthly samples from 15 sites.

2022 Season

Volunteers participating

Sites tested at least once

Sites tested at least 20 times

Data sheets entered in the Clean Water Hub

2023 Season

Volunteers participating

Sites tested at least once

Sites tested at least 20 times

Data sheets entered in the Clean Water Hub

In March, Prairie Rivers will release a report detailing the findings. Here are a few preliminary numbers that give a sense of how 2023 stacks up to the previous year.

2022 Season

Weeks in Drought

E. coli (geomean) at best site

E. coli (geomean) at worst site

"Poor" readings in Clean Water Hub

2023 Season

Weeks in drought

E. coli (geomean) at best site

E. coli (geomean) at worst site

"Poor" readings in Clean Water Hub

Drought continues to limit where we have flowing water. Sometimes, most of the water in a creek is coming from sewage treatment plants, which are able to remove some pollutants but not others. E. coli bacteria (an indicator of fecal contamination) continues to be high in most waters, likely coming from multiple sources. Looking at E. coli averages (geometric means) for the 2023 recreation season, two swimming beaches in the county met the primary contact recreation standard (126 colonies/100mL) but only 1 of 14 streams with enough data to evaluate did, and three exceeded the secondary contact recreation standard (630 colonies/100mL). Due to restrictive state laws about “credible data”, these sites might appear on a list of “Waters in Need of Further Investigation” but won’t be counted on the 2024 Impaired Waters List.

We continue to work with partners locally and around the state on ways to interpret water quality data and make it more accessible.

Story County Water Monitoring Program

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