Birds from Erv

by Dan Haug | Jul 11, 2024

photo montage of Erv Klaas and a whooping crane

Erwin “Erv” Klaas died on Saturday July 6. His passing is a great loss for Prairie Rivers of Iowa. He served on the board since its founding in 2001, started an endowment for the organization in honor of his wife Janet, and was a reliable presence at our events.

I received the news of his death on Sunday while visiting the International Crane Foundation with my family. We were watching a whooping crane, and my mother immediately recalled a birding trip that Erv had led to Nebraska’s Platte River many years back, perhaps as a contribution for our church’s silent auction. Among the awe-inspiring flocks of thousands of grey-feathered sandhill cranes, Erv had his binoculars trained on a single white-feathered whooping crane and was trying to help the rest of the group spot it. Mom said it was like a page out of “Where’s Waldo!” It’s a fun image to recall a one-of-kind ornithologist who loved sharing his passion for nature with other people.

Let’s think of Erv whenever we raise our binoculars! Here are five other birds (plus one plant and two insects) that remind me of his life and legacy.

Horned lark. Photo by Kenneth Cole Schneider.

Horned Lark (Eremophila alpestris)

Shortly after I was hired, Erv took me for a driving tour of the Ioway Creek watershed. As an assistant commissioner for the Story County Soil & Water Conservation District (and a representative for the group on the Watershed Management Authority), he was well-aware of how some farming practices could degrade soil, water, and wildlife habitat, while other farming practices could preserve them. He pointed out examples of both on our drive. At one point, he told me to pull over so he could take out his binoculars and get a better look at a flock of non-descript birds hopping and fluttering about on the open fields. Up close, they’re adorable! Horned larks are gregarious birds that form large, mixed-species flocks, which could describe Erv too!

Drawing of a passenger pigeon hunt. (Public domain)

Passenger Pigeon (Ectopistes migratorius)

Erv believed that care for the land and its creatures is an ethical imperative. Toward that end, he organized a regular event where residents of Ames and the surrounding area would gather to read passages from Sand County Almanac and other essays by Aldo Leopold. One that I find especially moving is “On a Monument to the Pigeon,” first delivered in 1947, which includes poetic lines like this:

There will always be pigeons in books and in museums, but these are effigies and images, dead to all hardships and to all delights. Book-pigeons cannot dive out of a cloud to make the deer run for cover, or clap their wings in thunderous applause of mast-laden woods. Book-pigeons cannot breakfast on new-mown wheat in Minnesota, and dine on blueberries in Canada. They know no urge of seasons; they feel no kiss of sun, no lash of wind and weather. They live forever by not living at all.

Trumpeter swan, spotted on Ioway Creek watershed tour with Erv (2017-09-15)

Trumpeter swan (Cygnus buccinator)

The trumpeter swan could have gone the way of the passenger pigeon (there were only 69 birds remaining in the continental US in the 1930s) but the population has made an impressive recovery (63,000 by 2015). Erv is part of that conservation success story: in 1971 he joined the US Fish and Wildlife Service and conducted research on the effects of DDT on birds that helped lead to a national ban in 1973. It’s been a great joy to see large flocks of trumpeter swans on the lake at Ada Hayden Heritage Park, another of Erv’s signature projects. They also like CREP wetlands constructed to improve water quality; that’s where we spotted this one!

Vallisneria americana - by Fredlyfish4 via Wikimedia commons

Tape grass (Vallisneria americana)

This aquatic plant is an important food source for waterfowl and nursery for fish. It has an amazing pollination strategy, with boat-like male flowers and corkscrew-stemmed female flowers! Anne Kimber (my stepmother) studied this plant for her PhD and remembers Erv’s kindness when she ran into difficulties with the field work. I have similar memories. After some setbacks with a data analysis project, I received a phone call from Erv offering encouragement. He told me that I was a scientist in practice if not in credentials, that my work was important, and encouraged me to seek out collaborators and look for ways to bring it to completion. I took his advice.

Eastern pondhawk dragonfly, by Erv Klaas

Eastern Pondhawk (Erythemis simplicicollis)

This is one of many photos that Erv took of adult dragonflies and damselflies at Ada Hayden Heritage Park, continuing his dedication to science in retirement as a volunteer. The aquatic juveniles showed up in his nets when he surveyed benthic macroinvertebrates for the IOWATER program. He monitored water quality monthly at two sites on Ioway Creek from 2002 to 2015, at one point finding unusual bacteria results that were traced back to a cracked sanitary sewer. The IOWATER program is ended, but Prairie Rivers of Iowa continues to support volunteer water monitoring in Story County and is building tools and relationships to help groups across the state learn more from the data they are collecting.

Greater yellowlegs, by VJAnderson (CC-By SA).

Greater Yellowlegs (Tringa melanoleuca)

I saw one of these unmistakable shorebirds while paddling on the Skunk River below Ames. It was on its spring migration from the Gulf Coast to the Hudson Bay. They are pretty common now, but could be in trouble as the planet warms. Erv was deeply concerned about the impact of climate change on wildlife, water and people here in Iowa and around the world, and founded the Ames Climate Action Team to nudge the City government toward more aggressive action. It’s a great example of “think globally, act locally.”

A monarch obstacle course, with osprey overhead

Osprey (Pandion haliaetus) & Monarch Butterfly (Danaus plexippus)

While families were tagging monarch butterflies and doing hands-on educational activities at Ada Hayden Heritage Park, I spotted this osprey soaring overhead. The “Monarch Magic” event in 2023 exemplifies what Prairie Rivers of Iowa does best: initiating conversations and building partnerships to do things together that no one organization would have attempted on their own, and educating the public to deepen our connections to the places where we live. Our new pollinator specialist (Katelyn Rinicker) is already working on planning the next one. It’s one way Erv’s legacy lives on, even among people who never met him.

How Big is the Elephant in the Room?

by Dan Haug | May 15, 2024

Iowa has a lot of hogs, poultry and cattle raised in concentrated animal feeding operations (CAFOs). They produce a lot of manure. However, CAFOs are not evenly distributed across the state, and it’s rarely practical to haul the manure long distances. Do rivers with more CAFOs in the watershed have worse water quality? I was curious and recently completed a big data analysis project to find out. I’ve omitted some of the technical details in the interests of making this article easier to read, but hope to eventually submit this research to a scientific journal for peer review. Get ready for a nuanced, data-driven look at the elephant in the room!

Livestock Density by Watershed

The water quality data for this study comes from 60 sites in Iowa DNR’s ambient stream monitoring network. (Two sites were later dropped because of incomplete data). For each monitoring site, I delineated a watershed (the land draining to that point) and overlaid databases of animal feeding operations. CAFO density in these watersheds varies greatly: from 12 animal units per square mile in Cedar Creek near Bussey, to 883 animal units per square mile in the Floyd River near Sioux City.

Animal units are a way of standardizing herd size across ages and species. For regulatory purposes, one 1000 pound steer is equivalent to 10 pigs under 55 pounds, 2.5 pigs over 55 pounds, 55 turkeys, or 82 layer hens. Feedlots with at least 300 animal units are tracked in Iowa’s database. Feedlots with 500 animal units require a manure management plan, and feedlots with 1000 animal units require a construction permit. The Iowa Environmental Council continues to follow and raise concerns about these rules.

Initial Findings and Complications

In the article that inspired this project, “The Fair, the Marginal, and the Ugly”, Chris Jones used this same dataset to rank water quality in Iowa’s rivers and noted that the river with the worst water quality has the most CAFOs. The Floyd River had the highest nitrogen and total phosphorus, the third highest turbidity, and the sixth worst E. coli. Sticking with the same time period (2016-2020) and similar metrics, I plotted water quality against livestock density for 58 sites to see if the Floyd River is part of a larger pattern. For nitrate, yes; for total phosphorus, maybe; for turbidity and E. coli, no. The relationship with turbidity is weakly negative; rivers with muddier water actually tend to have fewer CAFOs in the watershed.

The best explanation for this is that there is a third factor influencing both water quality and CAFO density: terrain. CAFOs are most common in flatter parts of the state where construction permits are more likely to be approved and there is plenty of cropland nearby to spread the manure. The notable exception to the pattern is Bloody Run, a trout stream in northeastern Iowa. In 2021, the Iowa DNR approved the construction of a 11,600 head cattle feedlot in this watershed, despite the steep terrain and abundant sinkholes. Given the timing, I am excluding this site from analysis and hope we do not have to find out what happens to water quality when this much manure is added to an environmentally sensitive area.

Slope and cropland are also correlated with livestock density.

Primary drivers of water quality

To better understand the interactions of multiple variables without a lot of statistics, I like to color-code one of them (in this case, CAFO density) and then focus on a narrow range (in this case, watersheds with less than 160 animal units/square mile). You’ll see this technique several times in this article. This shows how slope and cropland in the watershed influence water quality, independent of CAFOs.

Slope: As you’d expect, turbidity in rivers is strongly correlated with the average slope of land in the watershed. Steep hills are more susceptible to runoff and erosion. Phosphorus and E. coli are also attached to sediment and carried by runoff, so are moderately correlated with turbidity, and weakly correlated with slope.

Cropland: Nitrate in rivers is strongly correlated with corn and soybean acres in the watershed. Long-term nitrate trends can also be explained by changes in cropping patterns (a replacement of hay and small grains with corn and soybeans). I’ve heard corn and soybeans described as a leaky system, and want to echo that. Whether the nitrogen comes from manure, ammonia, or soil organic matter, if you don’t have something green and growing in the early spring, you’re going to lose a lot of it.

Graph of turbidity vs slope for watersheds with few CAFOs

Nitrate vs cropland in watershed, for watersheds with few CAFOs

Manure and Bacteria in the Water

E. coli is a bacteria found in the guts of birds and mammals, an easy-to-measure proxy for poop in the water and the pathogens that might come with it. For many environmentalists, the reason for Iowa’s long list of impaired waters seems frustratingly obvious. Hogs, poultry, and cattle outnumber humans, dogs, geese, raccoons, and deer, so they must be the main source of E. coli. Here’s an example of that kind of thinking from a report by the Environmental Integrity Project.

“Iowa is America’s hog capital – and also one of the most unhealthy areas in America to swim in rivers and streams. That’s in part because of the vast amounts of hog waste and farm runoff polluting the state’s waterways.”

The same logic showed up in the watershed management plan for Ioway Creek (and some others like it), which assessed likely bacteria sources based on the population of various kinds of animals and the amount of manure they excrete per day. While the consultants were careful not to say that hog confinements in Hamilton County were the main reason for chronically high E. coli in the creek, I sure got that impression from reading the maps and tables.

Looking at livestock populations turns out to be an unreliable way to guess which rivers will have bacterial impairments. Statewide, there is no correlation between E. coli in the river and livestock density in the watershed. The three worst rivers for E. coli in this dataset (the Soldier River near Pisgah, Maquoketa River near Maquoketa, and W. Nodaway River near Shambaugh) have less than 320 animal units per square mile, on the low side for Iowa.

More sophisticated models take into account the fraction of manure that reaches streams, how long it takes to get there, and how much of the bacteria dies off in the meantime. Unsewered communities, geese on the beach, raccoons in the storm sewer, and cows wading in the creek produce much less manure than animals in CAFOs, but a larger fraction of the manure is delivered directly to the water when it’s still fresh. That’s not to say that manure from CAFOs have no influence on E. coli in rivers. Once rivers with slopes steeper than 4% were excluded, the remaining sites had a moderate correlation between E. coli and livestock density.

E. coli vs livestock density for sites with less than 4% slope

Manure Nutrients in the Water

If manure is applied to fields that are not too steep and set back from streams, during appropriate weather conditions, and especially if the manure is knifed into the soil, very little of the solids, E. coli bacteria and pathogens in the manure should reach streams. The same is not true of the nutrients in the manure. Nutrients cycle between different forms, and the more readily dissolved forms (nitrate and orthophosphate) can easily leak out of the root zone during periods when crops aren’t growing, and make their way to streams.

Watersheds with a high density of CAFOs tend to have much higher nitrate concentrations, but most of that is because those watersheds also have a large proportion of the land in row crops. However, focusing on sites with at least 80% of the watershed in row crop production, there is still a positive correlation between livestock density and both nitrate and total phosphorus.

In the science assessment for the Iowa Nutrient Reduction Strategy, manure was not treated as a challenge for nutrient reduction, it was treated as a best management practice. It makes a certain amount of sense: manure is a slow-release fertilizer that adds organic matter to the soil. Compared to plots fertilized with commercial fertilizer, plots fertilized with swine manure had 4% less nitrate loss by 46% less phosphorus loss, mainly due to soil improvements that reduced the amount of runoff. However, those agronomic trials must have used a different set of application rates than usually occurs in practice. If you look at both commercial fertilizer sales and manure availability, counties with many CAFOs apply nitrogen and phosphorus at higher rates, with consequences for water quality. Here’s one study from Minnesota and another from Iowa that document this.

Closing thoughts

Prairie Rivers of Iowa has worked with some large swine and cattle producers who were early adopters of cover crops and who are very careful about how they manage manure. We salute their efforts to improve soil health and protect water quality. A study like this can only address the impacts of the industry as a whole.

Swine manure leaked into a creek in Greene County in summer of 2023.

This project was funded in part by a research grant from the Raccoon River Watershed Association, which has been monitoring water quality in Greene County. Last summer, the group watched with alarm as hog manure leaking from an earthen storage basin turned the water in a creek brown and caused the dissolved oxygen in the water to drop to zero. These kinds of incidents happen way too often, but usually affect a small stretch of stream for a short period of time, so don’t show up in monthly water quality datasets.

The correlations between water quality and livestock density disappeared entirely when I looked at two drought years (2021-2022). During dry periods, runoff and tile drainage from farmland is minimal, but effluent from sewage treatment plants and industry (including meatpacking plants) can have a bigger influence on water quality. Manure from CAFOs definitely impacts water quality in Iowa, but if we’re too quick to blame them in every situation, we may miss what’s really going on.

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

Can Infrastructure Spending Help Iowa’s Polluted Rivers?

by Dan Haug | Jan 1, 2024

The display department for the plans. If you've read Douglas Adams, you'll appreciate the joke.

“But look, you found the notice didn’t you?”
“Yes,” said Arthur, “yes I did. It was on display in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying Beware of the Leopard.”

– Douglas Adams, The Hitchhiker’s Guide to the Galaxy

I was reminded of this scene after spending a long day cross-referencing the Raccoon River TMDL (a pollution budget for nitrate and E. coli) with permits and monitoring data for wastewater treatment plants. In this case, I suspected that polluters were getting away with something, but I’ve had just as much trouble finding information when I wanted to document a success story.

Effluent limits for nitrogen are not strict. Wastewater treatment plants and meatpacking plants in the Raccoon River watershed routinely discharge treated wastewater with nitrate 4-6x the drinking water standard. Why is this allowed? The 2008 Raccoon River TMDL capped pollution from point sources at the existing level, rather than calling for reductions. Due to limited data, the wasteload allocations were an over-estimate, assuming maximum flow and no removal during treatment.

That’s all above board, but someone else at the DNR went a step further. Wasteload allocations in the TMDL were further inflated by a factor of two or three to arrive at effluent limits in the permits, using a procedure justified in an obscure interdepartmental memo. The limits are expressed as total Kjeldahl nitrogen, even though the authors of the TMDL made it clear that other forms of nitrogen are readily converted to nitrate during treatment and in the river. In short, the limits in the permit allow more nitrogen to be discharged than normally comes in with the raw sewage!

For example:

The Storm Lake sewage treatment plant has an effluent limit of 2,052 lbs/day total Kjeldahl nitrogen (30-day avg). Total Kjeldahl nitrogen in the raw sewage is around 1000 lbs/day.
The Tyson meatpacking plant in Storm Lake has an effluent limit of 6,194 lbs/day total Kjeldahl nitrogen (30-day avg). Total Kjeldahl nitrogen in the raw influent is around 4,000 lbs/day.
I also checked a permit affected by the (now withdrawn) Cedar River TMDL. Same story. The Cedar Falls sewage treatment plant has an effluent limit of 1,303 lbs/day total nitrogen (30-day avg). Average total nitrogen in the raw sewage is between 1000-1500 lbs/day.
Confused about the units? That may be deliberate. Total Kjeldahl nitrogen includes ammonia and nitrogen in organic matter. Nitrogen in raw sewage is mostly in these forms, which need to converted to nitrate or removed with the sludge in order to meet other limits and avoid killing fish. Nitrogen in treated effluent is mostly in the form of nitrate. At the Tyson plant, the effluent leaving the plant has around 78 mg/L nitrate, versus 4 mg/L TKN, but figuring that out required several calculations. At smaller plants, the data to calculate nitrate pollution isn’t even collected.

As part of the Iowa Nutrient Reduction Strategy, large point source polluters are supposed to evaluate the feasibility of reducing nitrate to 10 mg/L, and phosphorus to 1 mg/L. Tyson did a feasibility study for phosphorus removal, and is now adding new treatment to its Storm Lake plant. However, it is not required to evaluate or implement further nitrogen reduction, “because it is already subject to a technology-based limit from the ELG.” This federal Effluent Limitation Guideline was challenged in court by environmental groups this year, and is now being revised by the EPA. It allows meatpacking plants to discharge a daily maximum of 194 mg/L total nitrogen!

Fortunately, all this creative permitting has little impact on the cost and safety of drinking water in the Des Moines metro. According to research in the TMDL, point sources only account for about 10% of the nitrogen load, on days when nitrate in the Raccoon River exceeds the drinking water standard. However, the figure is much higher (30%) for the North Raccoon River. I started looking at permits and effluent monitoring because I was trying to explain some unusual data from nitrate sensors, brought to my attention by friends with the Raccoon River Watershed Association. During a fall with very little rain (less than 0.04 inches in November at Storm Lake), nitrate in the North Raccoon River near Sac City remained very high (8 to 11 mg/L). The two largest point sources upstream of that site can easily account for half the nitrogen load during that period.

I was glad to be able to solve a mystery, and hope that this investigation can lead to some tools and teaching materials to help others identify when and where point sources could be influencing rivers. The load-duration curves in the 200-page Raccoon River TMDL are very good, but some people might benefit from something simpler, like this table. In general, the bigger the facility, the smaller the river, and the drier the weather, the more point sources of pollution can influence water quality, and the more wastewater treatment projects can make a difference.

Spreadsheet for estimating impact of wastewater.

I made this table to estimate how biological nutrient removal in Nevada and Oskaloosa (about 1 MGD each) could improve water quality in the South Skunk River (about 1000 cfs on average near Oskaloosa, but there could be greater benefit in tributaries, or when rivers are lower).

In this work, I’m supported by partners around the state and a grant from the Water Foundation. The project (Movement Infrastructure for Clean Water in Iowa) focuses on building connections and shared tools around water monitoring, and will continue through this spring and summer. The funders’ interest is in helping the environmental movement make the most of the “once-in-generation opportunity” presented by the Inflation Reduction Act and the Bipartisan Infrastructure Law. This fiscal year, the Bipartisan Infrastructure Law is adding $28 million to Iowa’s Clean Water State Revolving Fund, which provides low-interest loans to communities to replace aging sewer systems and treatment plants. Can that infrastructure spending help Iowa’s polluted rivers? We won’t know for sure without better use of water quality data, and greater transparency in state government.

Five Stages of Watershed Awareness

by Dan Haug | Oct 4, 2023

October is Watershed Awareness Month, by proclamation of Story County Conservation Board and city councils in Ames, Nevada, and Gilbert. Okay, so what exactly do we want people to be aware of? I would suggest the following progression…

Stage 1: What’s a watershed? Who cares?

A watershed is the land area that drains to a common outlet. Imagine a river valley between two mountain ridges. Now replace that mental image with gentle hills–we’re in Iowa. But more important than knowing the definition is understanding why it’s important: because water flows downhill, actions on land can have consequences for downstream water bodies.

Perhaps the best illustration of this principle is an incident from 2020. Following a power outage, some Hy-Vee employees in Ankeny poured 800 gallons of spoiled milk down a storm sewer, turning the nearby creek white, killing 2,000 fish, and costing their employer almost $25,000 in fines and restitution. The silver lining of this boneheaded decision was that it made the news and reminded many Iowans that yes, storm sewers drain to rivers (usually without any treatment) and so we should think twice about what we pour or let wash in. The same principle applies to ditches, gullies, and drainage tiles.

Want a more positive framing? Watch this one-minute video we created with the City of Ames about the South Skunk River, and how cities and farms in the watershed can make a difference.

Stage 2: What’s my watershed(s)?

It’s one thing to know that my actions could (in principle) help or harm some downstream water body. It’s another thing to know that what goes down my neighborhood storm drain ends up in Ioway Creek at Brookside Park, a place where I’ve taken my kids to play. In 2018, we partnered with Story County Conservation to put up watershed and creek signs, in hopes that more people make those kinds of connections.

Creeks flow to rivers and rivers flow to the sea (except in endorheic basins) so we live in multiple, nested watersheds. A convenient way to represent this is with the US Geologic Survey’s Watershed Boundary Dataset, which has mapped American watersheds at six levels and assigned them each a unique hydrologic unit code (HUC). You can look up your “watershed address” with our interactive map. For example, that grocery store in Ankeny is in the lower Fourmile Creek watershed, within the watershed of Red Rock Lake, within the watershed of the Des Moines River, and within the upper part of the giant Mississippi River basin.

Stage 3: Who are the other people in my watershed?

One reason to learn which watershed you live in is to connect with other people who are concerned with flooding, water quality, fisheries, and recreation.

Twenty-eight watersheds in Iowa have a Watershed Management Authority with representatives from local governments in the watershed (cities, counties, and soil and water conservation districts) who might collaborate on water quality or flood control projects. Fourmile Creek WMA is one of the more active WMAs; its member jurisdictions pooled money to hire a watershed coordinator who can work with farmers and landowners. In some watersheds, farmers and landowners have access to additional cost-share programs or receive higher priority when they apply.

In some watersheds, a volunteer group, land trust, or other non-profit organization organizes projects to protect the water or raise public awareness. For example, the lake at Ada Hayden Heritage Park in Ames has a friends group, while the Raccoon River has a volunteer Watershed Association in addition to three WMAs.

Caveat

Unfortunately, I’m not aware of any central clearing house where one can find out what groups and projects are active in your watershed. I’m also not aware of any plans by state leaders to provide WMAs with stable funding or to delegate to them any powers that would help them accomplish their tasks. Watershed projects tend to be grant-funded (and thus short-lived) and watershed coordinator jobs often have high turnover.

Stage 4: What are the issues in my watershed?

Some watersheds have management plans (like this one for Fourmile Creek) that identify creek- or lake-specific problems and solutions. However, in many cases, the data needed to evaluate a problem and track progress toward solutions is missing until volunteers, universities or local government step up to do monitoring.

Knowing which issues go with which watershed can help us prioritize and find solutions.

Not every stream has the right conditions to support a trout fishery (like Bloody Run in Clayton County).
Not every stream has a history of destructive floods (like Fourmile Creek in Polk County).
Not every lake or reservoir has suffered from toxic algae blooms (like Brushy Creek Lake in Webster County).
Not every river is deep enough and has access for canoeing (like the South Skunk River in Story County).
Not every river affects the supply and safety of drinking water for thousands of people (like the Raccoon and Cedar rivers).

Stage 5: How big are the problems and solutions in my watershed?

The most difficult thing to understand about a watershed is the scale. It helps to have some familiar reference points. Here are some of mine. (I’ve used an app that makes it easy to delineate a watershed for any point of interest. The area is rounded to the nearest 100 acres.)

1,000 acres: Creek at Tedeco Environmental Learning Corridor, Ames.
5,900 acres: Peas Creek at the Ledges State Park.

At the HUC12 scale, most creeks are too wide to jump across, but shallow enough to wade. Watersheds are small enough to fit in one county.

14,100 acres: Walnut Creek at Neil Smith National Wildlife Refuge
24,000 acres: Bloody Run at Marquette.
56,800 acres: Fourmile Creek at Sargent Park in Des Moines.

At the HUC10 scale, it might be called a creek, but it often has enough water to float a canoe, and watersheds usually cross a few county and city lines.

132,700 acres: Ioway Creek at Brookside Park in Ames.
173,500 acres: Maquoketa River at Manchester.
209,300 acres: South Skunk River at River Valley Park in Ames.
356,100 acres: Rathbun Lake

At the HUC8 scale and beyond, the rivers are big and the watershed meetings can involve many jurisdictions and long drives.

586,400 acres: Floyd River at Sioux City
1,285,200 acres: North Raccoon River at Squirrel Hollow Park in Jefferson
2,306,200 acres: Racoon River at Waterworks Park, Des Moines
3,733,300 acres: Des Moines River at Saylorville Reservoir
97,191,700 acres: Mississippi River at Dubuque

For each of these watersheds, you’d need to plant about a third of the cropland to cover crops to reduce nitrogen and phosphorus in the stream by 10%. Most watershed plans will include more ambitious long-term goals and more complicated scenarios to achieve them, but this is a handy benchmark for thinking about the scale of change needed. Reaching the 1/3 mark for cover crops in a watershed would be good progress toward our 45% nutrient reduction goals and could produce a big enough improvement in water quality in the stream that we could conceivably measure it, though maybe not with test strips (i.e. from 10 to 9 mg/L of nitrate, from 0.40 to 0.36 mg/L of total phosphorus).

I don’t mean to discourage anyone, but I’m not aware of any watershed project in Iowa that has achieved success on this scale.

Appreciating Water and Wastewater Workers

by Dan Haug | Aug 23, 2023

Water and Wastewater Workers of Iowa Week!

In August the governor issued a proclamation recognizing these essential workers. I’ve had the privilege to get to know some of the folks who make sure the water in the tap is clean enough to drink, that the wastewater we flush doesn’t contaminate rivers, and that the storm sewers drain the streets without causing downstream flooding or pollution.

Ames WPCF Superintendent Tyler Ver Meer at an open house. Note the watershed map!

Sure, these kinds of jobs can involve reading meters, reviewing construction documents, doing inspections, and testing water quality. But it can also involve live-trapping turtles to stop them from damaging an expensive baffle curtain in a wastewater treatment lagoon by sitting on it (Tim Mattingly, City of Gilbert). It can involve handing out rubber duckies and demonstrating a flood model for kids at a school science night (Liz Calhoun and Jake Moore, Ames Public Works). It can involve taking time out of a busy schedule to attend meetings about watersheds and water monitoring (thanks to staff from Ames, Gilbert, Nevada, Roland, and Huxley who have come to mine). And it can involve canceling that meeting and rushing to the sewage treatment plant to help contain a spill when a valve breaks (this happened once to Ashley Geesman and Neil Weiss, Ames Water & Pollution Control).

I’ve been getting even more appreciation for wastewater treatment plants and the people who run them as I’ve researched and filmed Facts 31-35 of our weekly video series, “The Clean Water Act: 50 Years, 50 Facts.”

At a basic level, sewage treatment involves harnessing microbes to break down organic matter that would otherwise consume the oxygen in the water as it decomposes, and improving water clarity by allowing the solid material to settle out. Widespread secondary treatment of wastewater has taken care of some of the worst pollution that was affecting America’s rivers when the Clean Water Act was passed in 1972. But processes aimed at TSS (a metric of water clarity)and CBOD5 (a metric of oxygen consumption) doesn’t always get various forms of nitrogen (nitrate and ammonia), phosphorus, E. coli bacteria, or chloride down to an acceptable level. We’ve seen that in some our water monitoring results.

However, communities in Iowa continue to invest in improvements to their sewage treatment systems. NPDES permits have to be renewed every five years, and additional requirements come into play when a facility is renovated to increase capacity or replace deteriorating infrastructure. Some examples from the South Skunk River watershed include:

The City of Nevada is building a new plant (to be completed in 2024) that will include systems to remove additional nitrogen and phosphorus. Ames, Oskaloosa, and Newton also are planning nutrient removal systems.
The City of Ames spends over $3 million each year to repair or replace aging sanitary sewers.
The City of Gilbert installed an extra stage to better treat ammonia during the winter months.
A homeowner’s association near Gilbert is switching its water source to reduce the need for water softeners and the chloride (salt) pollution that comes with it.
Over the last decade, UV disinfection systems to address fecal bacteria have been installed in sewage treatment plants in Ames, Newton, Story City, Huxley, Roland, Gilbert, Cambridge, and a neighborhood association. Colfax uses chlorine disinfection. Oskaloosa, Maxwell and Nevada have upgrades in the works.

However, if non-point sources of pollution like agricultural runoff and stormwater aren’t addressed, cities and towns reach a point of diminishing returns where sewer rates are going up but water quality in the river isn’t getting noticeably better. That’s why it’s exciting to see more water utilities breaking out of traditional silos and partnering with farmers on conservation projects in their watersheds.

(Edit 2023-12-29: The numbers I was using are potentially confusing and not relevant to the point I was making, so I have deleted them. According to models used for the Iowa Nutrient Reduction Strategy, point sources of pollution like wastewater account for 5% of the nitrogen load and 12% of the phosphorus load during the 2006-2010 benchmark period. The South Skunk River as a whole has a similar breakdown, but the stretch between Ames and Colfax has a higher percentage of pollution from point sources.)

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