Restoring Native Plants in Riparian Areas of Turkey Run

Abstract

The paper outlines the problems with the health of Turkey Run tributary and the ways in which one could rehabilitate certain sites along the bank to improve the health of the stream. Over time, the health of Turkey Run has decreased so it is imperative to restore the stream to a decent stream rating.  The text refers to different conservation sites which outline the parameters for maximum health of suburban streams as well as data taken by different AP Environmental classes to assess the current state of Turkey Run.

Introduction

The headwaters of Turkey Run tributary begin in northern Upper Arlington from stormwater drainage, and runs through and between residential and commercial areas. This, then, is the reason there are major problems with the health of the stream because the amount of runoff from nonpoint sources in the area is large. “Riparian zones help to prevent sediment, nitrogen, phosphorus, pesticides and other pollutants from reaching a stream,” so it is important to strengthen Turkey run with native plants (http://www.bae.ncsu.edu/programs/extension/wqg/sri/riparian5.pdf, 1*). The biggest problem is the fact that the stream and the areas around the stream are not maintained, so there has been gradual degradation.

Based on research done by the EPA, Turkey Run is not a very healthy stream. Both in 2001 and 2005, water quality tests were done to assess temperature, pH, dissolved oxygen content, dissolved solids, suspended solids, as well as levels of hard metals. Any figures that stood out as poor or very poor were underlined. The data in 2001 was not as extensive as that in 2005, because it only measured IBI (Index of Biological Integrity), ICI (macroinvertebrate communities), and QHEI (Qualitative Habitat Evaluation Index).Two of these data parameters were underlined as indicating very poor levels of macroinvertebrates and other organisms usually found in urban streams (http://www.epa.ohio.gov/portals/35/documents/OlentangyTSD.pdf, 17*). In 2005 more research was collected but overall, none of the data collected was too extremely out of place besides the low dissolved oxygen levels and high amounts of aluminum.  Despite the general lack of periodic data collection from Turkey Run, a lot can be told from these two data collections. In the future, however, there should be more frequent research conducted in order to assess the stream quality to be able to move forward with restoration  as well as upkeep.

The biggest problems with Turkey Run have to do with the development in Upper Arlington. Whether the stream is channelized to make room for more businesses and homes or there is excessive nutrients in the water as a result of fertilizers, this leads to unhealthy water conditions as well as major erosion which I noticed at the Fire Station site because on either side of the bank there are large roots exposed. Generally, “riparian buffers should range from 25 to 100 feet wide on each side of the stream.” Turkey Run is not a good representation of this general rule (2). As a result, this stream is seen as more of a hassle and eyesore than a healthy part of the environment. 

Restoration of Turkey Run is an essential step to creating a healthier watershed around central Ohio. Fixing the issue at the root allows for the most cost effective plan for the stream while also making better choices about preserving what little nature we are still able to have in these urban/suburban areas. “The benefits of healthy streams include clean water, reduced flooding, reduced streambank erosion, reduced river and reservoir sedimentation, and lowered infrastructure costs,” which is entirely a positive reaction, there is no downside besides possible cost which in this case would be funded by nonprofits or the EPA (http://soilandwater.ohiodnr.gov/water-conservation/stream-restoration#OVE, 1*). 

It is absolutely necessary that along with the restoration of Turkey Run that some sort of education be involved with it as well to keep the problem from arising in the future. Not only should the restoration call for students and parents and any people in Upper Arlington to join and aid, but flyers should be passed out in neighborhood areas close to the stream and possibly even a few presentations at different schools in order to increase awareness. 

The most important first step in restoration is to establish a general width estimate for the buffer zones by finding the height of the floodplain, which would be the area around the bank where if the stream depth was multiplied by two the water and bank would meet. Based on research which would be conducted on the population densities of different plants, one can select what should be reestablished. If possible, it would also be important to erect some sort of boundaries such as a fence to prohibit people from mowing to the edge of the riparian zone, allowing for a diverse population of different plants to thrive. Depending on the soil makeup in different parts along Turkey Run, “the site may benefit from pre‑planting preparation, including lime and/or fertilizer, and disking or plowing.” (http://soilandwater.ohiodnr.gov/portals/soilwater/pdf/stream/stfs13.pdf , 4*). 

This would allow for the best conditions for plant growth and softer loamy soil would be better than silty clay soil.

Testing the soil content would be important for deciding if it is optimal for plant growth and determining if any nutrients are at higher levels than others. There is generally a larger concentration of clay or silty soils so it would be necessary to provide some loam and or more porous soil types to balance out soil types. Soil porosity is an important factor in riparian zones because the higher the porosity of soil there is a smaller chance that the stream will flood too much and damage surrounding areas. Lower porosity soils, however, are very good at holding nutrients which are necessary for plants, so it would be important to have a good mixture of soil to allow for plants to grow but not too many nutrients that it will cause issues for the stream.

Another big issue with Turkey Run is the fact that in the areas close to businesses there is litter and some businesses refuse to aid in the upkeep of the stream. While some businesses have cooperated and done stream cleanups every month, some refuse to do anything including not mowing to the edge of the riparian zone. With rehabilitation of this stream, it is vital to have cooperation from businesses as well as the community at large. This could be done by preventing redirection of the stream and “removing vegetation,” such as invasive species (2).

In order to assess the full impact of the lack of buffer zone along Turkey Run tributary, the area must be divided into quadrants and looked at for population density of certain plants. Depending on the results of testing, the initial question would be whether or not the area is overrun with invasive species such as honeysuckle. If it is, it would be removed immediately. Depending on the population of native plants in each quadrant, it can be decided how many should be planted there in order to maintain the health of the stream. 

If the stream’s health increases, the proof would be mostly seen with the chemical properties of the water, macroinvertebrate populations, and general appearance of the stream. Given that the native plants remove excess nutrients, one would expect to see a drop in nitrates as well as phosphates (http://ohioline.osu.edu/ls-fact/0001.html*). Macroinvertebrate count would be much higher, and more would be found from the different categories of stream health. It would be a slow, gradual change but over time more and more should be seen. The general appearance of the stream would be better because the vegetation in the buffer zone would be much more lush, extreme erosion would be much less prevalent because sediments would no longer be quickly redistributed, and the roots of plants would no longer be visible because there would no longer be erosion. 

Six AP Environmental classes tested the quality of Turkey Run’s water both in the 2014-2015 and 2015-2016 school year, in which a class of about 20-25 people were divided into about 4-5 groups and spaced evenly at different points up and down the stream. Students tested for nitrates, phosphates, turbidity, salinity, etc. and found no major chemical issues besides a slightly higher level of nitrates. Depending on the site that was tested, some places there were only leeches but in others there were some macroinvertebrates and even in some cases some small darter fish. Some sites found higher nitrates most likely came from runoff and decomposition of dead leaves and small organisms which contributed to the poor water quality. The turbidity was low and the water was very clear, however there was not very healthy water flow partially because there was a man-made dam installed which prevents any large input of oxygen into the stream.

* this link is no longer available