Fall 2021

Water Quality Takes Front Stage During Drought

Duckweed 2Among the many impacts this drought year has had on our region, one of the most noticeable for us has been the proliferation of floating aquatic vegetation on lakes and ponds, especially at Big Hollow Lake. 

Hot, dry, and calm conditions are the perfect recipe for growing duckweed, the floating plant that covers the surface of lakes and ponds throughout the region. With Big Hollow being just that, a big hollow, much of the lake is sheltered from the winds that, in more open lakes, help control duckweed. Add the fact that all of the lake’s developed amenities such as the boat ramp and beach are on the north shore, a prevailing southerly summer wind only serves to exacerbate the problem.

Years like this, when nearly the entire lake turns green, really bring our water quality issues to the forefront. Big Hollow Lake suffers from an excessive diet of nutrients, namely phosphorous, due to runoff and erosion across its 4,600 acre watershed. It’s not necessarily dangerous from a health perspective, it’s just that the resulting algae blooms really impact the intended uses of the lake such as fishing, boating, paddling, and swimming. 

We’ve been working on the lake’s water quality since at least 2014. It took until 2018 for the state to collect enough data to land the lake on the state’s list of “impaired waters,” in our case due to the excessive phosphorous and resulting pH issues. That qualified us for grants to finally do something about it and in 2019, in partnership with other agencies including the Des Moines County Soil and Water Conservation District, we landed a federal grant to hire a consultant (FYRA Engineering) to develop what’s called a Nine-Element Plan. This plan, coupled with the DNR-prepared Water Quality Improvement Plan (aka WQIP, aka TMDL for “Total Maximum Daily Load”), will identify the actions and practices to implement throughout Big Hollow Lake's watershed to improve the lake's water quality without having to take drastic measures like draining the lake like what was done at nearby Lake Geode State Park starting in 2018. 

Algae at beachFurthermore, once the Nine-Element Plan is approved by the EPA, the lake will then be eligible for federal funding through the Clean Water Act as well as other local, state, and federal programs. We anticipate the plan being complete this year, with federal approval coming sometime in 2022 after which we will start applying for funding.

Additionally, we recently started taking water quality samples in several locations throughout the watershed. The results of these samples will establish some “baseline” data for us to gauge improvements as conservation practices are applied in various areas throughout the watershed. Previously, water quality sampling had only been done in the lake itself.

So what does this all mean for water quality in the short term? What are we doing, or what can we do, about the vegetation already covering the lake? The short answer, unfortunately, is “not much.” In small ponds, aquatic vegetation can be controlled with chemicals or sometimes by mechanical means (skimming or aerating). But in a 178-acre lake that has 30 acres draining into it for every acre of surface water, chemical application is impractical. A single application sufficient enough to kill off the duckweed would cost hundreds of thousands of dollars, if not more, and the resultant decay of the dead vegetation would deplete the water’s oxygen, killing most of the fish. Considering the lake is well known for 15” crappie and 5-pound bass, that’s simply not a practical approach. 

What maybe is possible is blocking off and treating certain areas of the lake such as the beach and boat ramp areas. We’re actively exploring those options and may experiment in the coming years with different ideas. They may or may not work so bear with us as we try to figure this out. 

In the long run, however, the only way to improve water quality in the lake is to improve the water quality in the watershed. This is true not just at Big Hollow, but everywhere. We have to stop the nutrients from reaching the lake in the first place and that requires land management practices such as buffer strips, cover crops, streambank improvements, construction of sediment ponds, and many other things. There is no one silver bullet to improving water quality. It takes time and cooperation among landowners, homeowners, and agencies such as ours. And most of all it takes a willingness to see one of the county’s greatest outdoor recreation assets improved. 

We have no doubt that, together as a community, we’ll do just that. 

To learn more about our efforts to improve the water quality at Big Hollow Lake, visit our Water Quality Project page on our website. 

DMCC Recognizes Our Great Volunteers

Every year, we take a little time out of our summer to recognize the volunteers that help us with so many things. We do this at an annual volunteer recognition dinner which we have at Starr’s Cave. During the event, we always give awards out to volunteers that went above and beyond. Here are this year’s winners. 

Volunteer of the Year: Jim Steer
Jim has been a long time volunteer with our organization, having served over a decade as a board member and even after leaving the board, he continues to serve on our local foundation. He helped establish and continues to lead our bluebird box program, and has been a mentor to several staff members during his many years of service.


Volunteer Group of the Year: Southeast Iowa Astronomy Club

The Southeast Iowa Astronomy Club (SIAC) has operated the Witte Observatory Complex at Big Hollow for decades. As the park has grown, so have the numbers of people wanting to see the cosmos. The visitation to the park has grown so much that in 2019, there were times when the volunteers at SIAC had to accommodate 100+ people in a night. Then the pandemic struck and everything shut down. But as soon as they could, the great volunteers with the astronomy club worked with us to figure out how to still connect people to the wonders of the cosmos safely. They worked with the camp host to schedule small group showings for campers and set up a reservation system through which they can do showings with small groups. Like with everything else pandemic-related, they had to learn to adapt to a new normal and they did it well.


Environmental Educators of the Year
This year’s award went to husband and wife team, Dave and Vicki Philabaum for their tireless efforts connecting camp kids to the wonders of astronomy. As we brought back summer camps post-shutdown, the Philabaums were our go-to contact at SIAC to arrange showings with camp kids. They were always accommodating and their knowledge of the cosmos made the observatory experience something those camp kids likely will never forget.


Annual Report Now Available 

Every year, Des Moines County Conservation publishes an annual report highlighting its major achievements and providing details on its operations, programming, and finances. All annual reports can be found here.

EE Update:

We’re back in the schools running programs and it feels great! New this year, we are renting out program kits! Teachers can rent a program kit from us to teach one of their favorite lessons. These kits contain everything needed to teach the program including the lesson write-up. Our latest program guide is on our website. If you’d like to schedule an in-person program or kit rental call Starr’s Cave Nature Center at 319-753-5808.

This school year, Starr’s Cave staff is running an afterschool club at Aldo Leopold Intermediate School through Burlington Community School District’s PiECES program. Once a week we take a group of students into the Aldo Leopold Prairie to play games, journal, do citizen science, and learn about the natural world around them. The club is off to a great start, and we’re excited for the projects we’ve got planned for the remainder of the school year including building Leopold benches and bluebird boxes, monitoring bird feeders, and learning how to use a compass.  

We have partnered with Des Moines County Extension and Outreach to host a Growing Up Wild training on Saturday, October 23rd. Growing Up Wild is an early childhood education program for ages 3-7. The $5 registration fee gets you 4 hours of DHS training credit, snacks, and your own Growing Up Wild: Exploring Nature and Young Children Activity Guide! Participants should be prepared to spend time both indoors and out. If you have questions or would like to register, contact Dawn Dunnegan at 319-217-9474 or dunnegan@iastate.edu.

Beginning October 1, Starr’s Cave Nature Center will be open Tuesday-Friday from 7:00am-2:00pm. Due to a busy schedule of programs, we encourage you to call before you stop by to make sure someone will be there. As always if you’re out here and the sign says “Open” feel free to stop in!

featured park: linder conservation area

Linder 1The Harold and Mildred Linder Conservation Area is a 105 acre parcel of land along 170th St., a mile west of Highway 61 between Burlington and Sperry. The land was partially donated to the county by the Linder Family in 2018. The remainder of the purchase was made possible through a REAP grant. The property is maintained as a conservation area so it’s primary purpose is wildlife habitat and natural resources. Activities such as hunting, hiking, and wildlife viewing are allowed on the property as per state laws pertaining to public wildlife areas. Portions of the property are still farmed through a local tenant agreement. Visitors should take care to avoid damaging crops.  

The effort to turn the Linder Property into a public wildlife area dates back nearly two decades when the landowner, local conservationist Harold Linder, suggested the conservation department purchase the property and turn it into a public wildlife area. Unable to secure the necessary grants, the project was tabled while the department focused on the major development efforts at Big Hollow and the Flint River Trail. Aware of their father's desire to see land protected and made available to the public, Harold's two children renewed the effort to have the conservation department acquire the property following his passing. Throughout 2016 and 2017, the conservation department worked with the Linders and the Iowa Natural Heritage Foundation, eventually agreeing to accept a donation of almost half the land's value and securing a REAP grant for the remainder of the purchase.