Artificial Lakes In Iowa

Lance Kinseth, Evening On Brushy Creek, ink

IN THE LATE 1980s, summer, I was hiking upstream on Brushy Creek.  I had come to this landscape because it was evident that this natural canyon would be under water due to the pending construction of an artificial lake.

I would amble and then perch, and listen to the orchestration of wild sound and look into the changing patterns of sun and shadow and color and, eventually, evening moonlight.

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In 1967, the Iowa DNR offered an immediately controversial proposal to flood this canyon.  The proposal was debated for 25+ years.  In 1998, the Iowa DNR sought two million dollars from the Iowa Lottery Fund for park/lake construction.  In 1989, construction of a lake and 6000 acre park was initiated (reducing the original proposal of a 1000 acre lake to a 690 acre lake).  

Local economic stimulus resulting from park visits and recreation outweighed the loss of a non-commercial natural canyon and its archeological and natural value/standing in its own right that had been developing so for millennia. 

The park and lake were seen as emerging from a relatively unused piece of local land.  There was limited sense of this landscape being already integral to a larger landscape.

Brushy Creek lies near the top of a river landscape the the Des Moines River Watershed that from here south to Boone involves steep valleys that ware forested due to the impossibility of agriculture being predominant and that had been proposed as a possible national park.

This particular area of this large steep river valley is home to rather exotic landscape such as Dolliver State Park, wildcat cave, woodman’s hollow, etc.  And there is a strong argument for maintaining continuity for, in no other reason, the eco-diversity that comes from having such a long wildlife corridor.  As a canyon creek it is uncommon in a flat table of agriculture and part of an edge--an ecotone--that begins to protect the larger Des Moines River valley--a diverse, wild precision gift to generations to come.  Indigenous flora an fauna favor undisturbed terrain and complex interrelationships across species.

Undeveloped Brushy Creek was uncommon in a state with less than one percent of the surface area publicly maintained for wildlife--49th among the states--where private land continues to be rapidly deforested. 

But as a canyon creek, it was a target for damming and artificial lake development.

We have learned to not see such landscapes.  Our identity is social, not bioregional.  And lake development in Iowa is social, not bioregional.  Brushy Creek lies within the Des Moines River drainage basin/watershed, a 14,540 square mile area.  Our approach is one of usage and commodity.  Our most honest “land ethic” has been essentially landless in terms of consideration given to the land.  Stewardship is more like depletion.   To do something, land must be used.  What has saved much of the Des Moines River Greenbelt is that it is too steep to use.  “nothing” vs. economic opportunity seems an easy choice to make.  But when we look at our use of the land, we can begin to see how much it costs us to use it, and the cost is not a one-time cost, but rather an perpetual economic drain, AND a continuing loss of the free economic quality of the landscape that appears to us to be doing nothing.  We miss the precision and wisdom of the landscape and we overlook the degrading feedback we get from using it.

If you could have come to this creek before it became a lake, you might have been whirled around both by little things and by the large wild vestigial tail of a glacier.  You see it in the glacial-made cobble and the deep ice sheet-cut shape of this region.  Going down in to such a gap in the Earth can have the feel of being in a kiva, a place of deep origination.  And when we go to such places and slow down, the day-today, moment -by-moment events of such a landscape become clarified as life to us, sustaining and renewing the landscape rather than depleting it, sustaining a deep foundation, a deep ground.

In Desert Solitaire, Edward Abbey describes a rafting trip with his friend Ralph Newcomb, down the Colorado River to see the Glen Canyon, that “portion of the earth’s original paradise,” before it was lost under the man-made Lake Powell.  The damming of Brushy Creek seems to pale in comparison to Glen Canyon.   And so, what chance for an obscure midwestern stream valley?

When I ambled on Brushy Creek, I saw enough to sway my vote.  There was a miracle of commonness, and a way to see something of value beyond a short-term view.  To paraphrase a geologist quoted in John McPhee’s Basin and Range, we see two generations forward and two behind.  How to talk about such wonder and a longer range economy in everyday budgetary terms?  

The commonness of Brushy Creek is a rarity in Iowa.  In the long run, we would not be saving this place for wildlife (which is the typical argument); we would be saving it for our own deep interest as an ecotone--an insulating edge between use and the larger Des Moines River Greenbelt.  Instead, we opted for a holding tank for agricultural runoff that we will have to pay a bundle of $$$ for to keep functional for recreation.

Brushy Creek Lake

The watershed or drainage area for Brushy Creek that is dammed to create a lake drains 56,919 acres with 48,635 crop acres into 690 acre lake.  The lake to drainage area is a ratio of 1/82 the size of watershed.  A ratio of 1/20 is the preferred high end ratio to sustain lake quality.  Right off the bat, this means a big problem.  If all else was OK, that would lead to the major problem being sediment coming into the lake.  But in the case of Brushy Creek, even the sediment from such a large drainage means a faster and a larger problem.  As a result, an estimated 16,194 tons of sediment runs into the lake annually.

The quality of the lake is compromised even more severely by the fact that the majority of land use in the Brushy Creek drainage basin is industrialized agriculture.   The cover has been stripped meaning more silt for the lake and more soil loss for the farm.  The drainage area for Brushy Creek is 86% cropland--90% corn/soy rotation with high chemical usage.  The rest involves 1,254 acres of farmsteads, urban development [Duncombe/Vincent], and commercial development with household septic and municipal treatment.  There are 50 landowners with livestock and 6 confinement feedlot operations producing manure.  And there is an anhydrous ammonia plant in center of watershed.

From 2009 through 2011, there was a $1.5 million project to make Brushy Creek above the lake safe for water “contact recreation.”  Upper Brushy Creek was the site of multiple fish kills that resulted then primarily from problems with manure transport from feedlots into streams.  At the end of the project, there was still E. coli at the lower end of the project, but declared safe for contact.

A ground-down glacial flat landscape that is significantly tiled to maximize dry fields speed up nitrogen flow into streams.  In Brushy Creek lake, nitrates, nitrites, chloride, phosphate, alter natural water Ph [from 7], and lower dissolved O2 levels and contribute to poor water clarity.

Brushy Creek Lake is largely runoff-fed, not spring-fed.

DNR online park description for Brushy Creek State Park presents extensive press on the threats to water quality to encourage public awareness of the extreme need to do many things to try to maintain some of the water quality.  By their nature of being artificial “impounded water,” lakes such as Brushy Creek do provide recreation and economic value to the local region, but they are high-cost projects if they try to maintain both the physical body of the lake {due to high levels of incoming sediment that is trapped there by damming] and water quality.  And continued required maintenance will never stabilize the degradation that they endure. 

Costs: There are, of course, 

• the millions of dollars to construct artificial lakes,
• ongoing costs to maintain a park vs. an undeveloped property (e.g., 2011, for Brushy Creek: shower, $168,000, salaries, machinery, housing, infrastructure, shelters, utilities, roads, as well as flood repair (e.g., 2011, FEMA funds, $30,272) so that facilities can be used, and
• ongoing costs to mitigate sediment and chemical intake, spills and land application of manure [filter strips, wetlands, timber stand improvements, conservation cover, household septic system improvement, stream bank stability, minimum tillage, open-air hoop building cattle confinement, denitrifying bioreactors, grass waterways, terraces, “proper” manure-spreading, etc.]  These costs are extensive [quickly reaching $100,000 to $million for even smaller interventions] and will not meet the needs that exist in such large drainage areas, due both to such high costs [and the absence of government subsidies at such a level of demand and agricultural producers resistance--due either to making a living with low profits or disinterest or corporate contribution that are noteworthy but minuscule compared to the need].

Summary

A University of Iowa study suggests that Iowa has 48 glacial lakes/32,000 acres and 148,000 acres of artificial or “impounded water.”  

Glacial lakes in Iowa tend to be shallow allowing for high nutrient content from agricultural runoff.  In Iowa, lakes stand a good chance of becoming eutrophic [i.e., “a water body rich in nutrients and so supporting a dense plant population, the decomposition of which kills animal life by depriving it of oxygen”] as opposed to remaining oligotrophic [i.e., “low in plan nutrients and containing abundant oxygen in the deeper parts”].   As a result, there will never be nutrient-clean lakes in Iowa, and the costs of mitigating both sediment inflow and nutrient pollution will be high to the degree that a decision is made to dredge or do up-stream mitigation.  Overall, the Federal and state regulations favor a rather unrestricted agriculture that dominates the acres in all of these lakes’ watersheds.