McFarland LakeResearch Report

By: Michael Schmidt

Instructor: Mimi WagnerCompleted: Fall 2013

Class: LA 490L Independent Study

Iowa State University Landscape Architecture

Table of Contents1. Introduction

2. Background

3. Lake Conditions

4. My Findings

5. Recommendations

2.1 Site context2.2 Watershed2.3 Tile System

3.1 Fish Data3.2 Water Quality

4.1 Watershed4.2 Tile Maps4.3 Historic Photos4.4 Discharge Pipes and Culverts4.5 Vegetation Along Shoreline4.6 Shoreline Erosion4.7 Activity Zones4.8 Inlet Channels

5.1 Agriculture Watershed5.2 Shoreline Vegetation4.3 Shoreline Erosion4.4 Site Use Additions

pg.4

pg.5

pg.5-7

pg.7-15

pg.7-15

pg.7-9pg.9

pg.9-11pg.12

pg.12-13pg.13pg.14pg.15

pg.pg.

pg.pg.

pg.5-6pg.6-7

pg.5pg.5pg.5

6. Appendix6.1 Graphic6.2 Graphic6.3 Graphic6.4 Graphic

pg.pg.pg.

pg.pg.

6.5 Graphic6.6 Graphic6.7 Graphic6.8 Graphic6.9 Graphic6.10 Graphic

pg.pg.

pg.pg.

pg.pg.

7. Acknowledgments pg.

McFarland park is a public park near Ames, IA. Located within the park is a small man made lake named McFarland Lake, the offices of the Story County Conservation group, a public hiking trail, campgrounds, nature restoration areas, and many more activities. The purpose of my studies was to learn about lake shore management and all of the surrounding conditions that affect lakes. McFarland Lake provided a site with many positives and negative conditions current to lakeshore management. The Story County Conservation Group’s interest in the project and the resources they provided contributed to a successful research project. I am currently a fourth year student at Iowa State University seeking my bachelors degree in Landscape Architecture, with a double major in Environmental Studies. I have been in and around lakes my whole life and have developed a great interest in learning about them and what I can do as a Landscape Architect to improve lake conditions. I consulted with my professor, Mimi Wagner, about doing this research project, as she has the background and resources for this type of work, and would help me gain a better understanding of lake shore management. Together we selected McFarland Lake for our study site and developed the following report of my findings.

McFarland Park is a 200 acre park with a diverse land cover that contains a mix of tall grass prairie, woodland, and wetland habitats. The park attracts many visitors for activities including fishing, camping, picnicking, and hiking. The park contains a hard surface walking/hiking path called the Touch-a-Life trail that attracts many visitors from all over Story County and brings many people to McFarland Lake. The Story County Conservation offices. are located in the park, making McFarland Lake one of their most important assets and a showpiece of their hard work. The conservation groups hosts many classes and public events that help study and improve McFarland Park. It shows their eagerness to keep learning about improving their lake.

1. Introduction

This project will be used as a resource for people wanting to know about McFarland lake as well as a detailed report for Story County Conservation to support their plans in moving forward to improve the lake. The Conservation Group’s goals are to gain a better understanding of the lake, and to learn how surrounding practices may be negatively impacting it, to develop a plan to help improve erosion problems, and to create new activity areas on site. These areas would include handicap accessible locations to the lakeshore and a new canoe access point that would make it easier to get a boat in and out of the lake.

2. Background

2.1 Site Context

McFarland Park is located approximately 3 miles northeast of Ames, IA along Interstate 35. Ames has a total population of 60,634 according to the 2012 United State Census data. The 200 acre park is surrounded by agricultural fields and feeds into the South Skunk River. The park provides camping, conference rooms, cross country skiing, free parking, hiking, off-road bicycling, picnic tables, pond and river fishing, and public rest rooms.

Inte

rsta

te 3

5

Lincoln WayLincoln Way

Highway 30

Iowa StateUniversity

Ada Hayden Lake

Hig

hway

69

McFarland Lake

2.2 Watershed

The area of land that drains into McFarland Lake is its watershed. After calculating the watershed size from the topography maps of the area, the total size is 420.5 acres. The “My Findings” section of this document will provide detail of what land cover is in the watershed and what factors may be affecting the Lake.

2.3 Tile System

Tile Systems are put in to agricultural fields to help drain water off the land faster. Although this makes the crop fields more successful and efficient, it can cause dangers to bodies of water downstream such as McFarland Lake. A tile drainage system is located in the agricultural fields directly west of Interstate 35.

3. Lake Conditions

McFarland Lake Watershed & Topography Map

3.1 Fish Data McFarland Lake is a public fishery that is managed by the Iowa Department of Natural Resources. This data was provided was provided by Andy Otting and Ben Dodd from the Boone County DNR. They Report a mix of Bluegill, Largemouth Bass, Catfish, Sunfish, and Grass Carp with the two primary fish being Bluegill and Largemouth Bass. The water in McFarland lake is very clear and with the surrounding dense vegetation, it limits the effectiveness of some of the sampling gear. With that being said, the following data was collected in 2012 with methods of electrofishing and hoop netting. The charts below show the length in inches of the fish caught and the relative weight of the fish. The Largemouth Bass population in McFarland Lake is likely larger then what the data currently shows. When the DNR conducted the sampling of Largemouth Bass they used Electrofishing as their sampling type. They collected

Watershed LimitTile SystemMcFarland Lake

0 2 4 6 8 10 12 14 16 18

20

40

60

80

100

120

Rel

ativ

e W

eigh

t (W

R)

Length (in)

Largemouth Bass Data

The Bluegill population in McFarland Lake is one of the more dominant populations. When the DNR conducted the sampling of Bluegill, they used primarily a hoop netting sampling technique. They were able to catch 37 Bluegill that ranged in length from 5 inches to 9 inches. The Bluegill had relative weights between 67 and 112. This is a larger range of difference in relative weights compared to the Largemouth Bass data due to the larger sample size of the Bluegill population. The majority of the relative weights of the fish sampled were right around 90, which means that the population is in balance.

0 2 4 6 8 10

20

40

60

80

100

120

140

Rel

ativ

e W

eigh

t (W

R)

Length (in)

Bluegill Data

a total of 8 large mouth bass ranging in lengths from 9.2 inches to 15.3 inches. All of the fish had relative weights between 85 and 106. The chart below shows the line of best fit through the points and shows that, on average, the Largemouth Population have a relative weight of 100 around the size of 10 inches, then gradually declines as size increases. Generally, a fish population is balanced with relative weights around 90. This shows the Largemouth Bass population appears to be balanced in McFarland Lake.

3.2 Water Quality The following water quality information is from the most recent data taken. It is a report done by James L. Anthony and the students of the Animal Ecology 410 class in the fall of 2000. Their report is titled: The Chemical and Biological Composition of McFarland Pond, Story, County, Iowa during the Fall of 2000. This report addresses the topics of bathymetry and morphology, temperature and thermal structure, pH, alkalinity, color, turbidity, chlorophyll, oxygen, major nutrients, flora and fauna, and microbiology.

McFarland Lake is characterized as a stratified aquatic system with declining temperatures with increasing depth. The thermocline is located around 12.8 feet to 14.4 feet, which is around the max depth of the pond. This shows that almost all living organisms in the pond are organisms that can survive above the thermocline. In late summer, the hypolimnion (the area below the thermocline) is nearly absent. From their findings in the summer of 2000, the temperature varied from 75.2 degrees Fahrenheit at the surface to 57.2 degrees Fahrenheit at a depth of 14.4 feet. The temperature was relatively consistent untill a depth of around 11 feet when it started to drop of drastically to the bottom depths of the lake.

Temperature & Thermal Structure

pH, Alkalinity, Color The pH, or acidity, in McFarland Lake was relatively high in shallow waters of the lake but declined and became more neutral in greater depths of the lake. Around the level of the thermocline, pH levels dropped of drastically. The alkalinity of a lake is the ability of the lake’s water to buffer changes in pH levels. The alkalinity levels of McFarland Lake were quite high and oscillated in depth. The color of the water shows the amount of dissolved substances in the water. The color of the water remained consistent through the water with the exception of a quick change at depths of 3 feet to 4 feet.

Turbidity, Chlorophyll, Oxygen Turbidity is the measure of suspended solids in the water such as sediment and phytoplankton. Turbidity levels in McFarland Lake remain low untill around the thermocline and then increase drastically at the thermocline and in the hypolimnion. The measure of chlorophyll in the water represents algal production and therefore represents a constituent

Ammonium and Total Phosphorus In freshwaters, the major limiting nutrient is total phosphorus. In 2000, the total phosphorus levels ranged from .29ppm to .11ppm. According to the US EPA, total phosphorus levels greater then .1ppm can become dangerous to humans and animals and cause digestive problems and other issues. The ammonium levels ranged from .38ppm to .29ppm in McFarland Lake. A lake should hope to have ammonia levels of around 0 because that would signify that the lake is in balance. Again, this data was collected in 2000 by the Animal Ecology 410 class at Iowa State University. These numbers have more than likely changed over the years and may not be exactly the same today. In the My Findings section of this report, I have had added predictions of how these levels may have changed and what we can do to fix them.

of turbidity. Levels of chlorophyll increase rapidly again at levels at and below the thermocline. This is likely due to the fact that light does not penetrate McFarland Lake below a level of 3.2 feet, and higher chlorophyll levels reflects dead or dying phytoplankton trapped below the thermocline due to changes in water density. Dissolved oxygen was also measured in the fall of 2000 at levels of 12mg/L at the surface and at 0.0mg/L near the bottom of the lake. The oxygen saturation ranged from 107% (supersaturated) to 10% near the bottom of the lake.

4.1 Watershed Characteristics The area of land that drains into McFarland Lake is its watershed. After calculating the watershed size from the topography maps of the area, the total size is 420.5 acres. This equals approximately ¼ the size of the Iowa State University’s campus. Over 75% of the land area in the watershed is not located in the park and is not under the control of Story County. This causes untreated water runoff that travels through multiple different land cover types that could bring in harmful pollutants to the lake. Located in the McFarland Lake watershed is cropland, grasses, open water, developed land, deciduous forests, herbaceous grasslands, woody wetlands, and herbaceous wetlands.

crops included in the 2012 cropland were corn, soybeans, and oats. Water runoff from these sites can be carrying chemicals used for the crops and be getting dumped off into the lake, causing excessive nitrogen and phosphorus levels. The agricultural land in the watershed should be monitored and it is encouraged that water runoff be treated for the lake to become heathier

The second largest land cover in the watershed is developed land, totaling 64.3 acres (15.3%). A ma-jority of this developed land is Interstate 35, located directly east of the lake. Although most of the water runoff from I-35 is captured in swales and taken away from the watershed, some pollutants from cars could be entering the lake. Other developed land includes the Story County Conservation offices, roads, and small homes on the farms. The land cover located directly around the lake’s edge are open water, woody wetlands, deciduous forests, herbaceous grasslands, and developed land. The land cover in this area is

Watershed Land Cover DataTable 1

Cropland (Corn, Soybeans, Oats)Grasses

Developed LandDeciduous ForestGrassland HerbaceousWoody WetlandsHerbaceous Wetlands

Land Cover Type Size in Acres

Total Watershed Size

269.30.75.1

64.314.260.74.9

Open Water

1.3420.5

Cropland64%

Herbaceous Wetlands0.3%

Woody Wetlands1.2%

Grasses0.2%

Open Water5.1%

Developed Land15.3%

Deciduous Forest3.4%

GrasslandHerbaceous

14.4%

4. My Findings

The largest percentage of the watershed is cropland, equaling 269.3 acres (64%). The primary

Land Cover Source: 2012 NASS Cropland Data Layer

Cropland

Grasses

Open Water

Developed Land

Deciduous Forest

Grassland Herbaceous

Woody Wetlands

Herbaceous Wetlands

2012 Land Cover and Tile Drainage Map

Tile System

Land Cover Source: 2012 NASS Cropland Data Layer

maintained well by Story County and is less of a concern in terms of water runoff as compared to the surrounding cropland.

4.2 Tile Drainage Maps

McFarland Lake Tile Systems Map

Watershed Boundary

Tile System

McFarland Lake

Tile drainage systems have been in the agricultural fields to the east of McFarland Lake. The systems were put in to help drain their agriculture fields by transporting water off their land faster. Although this makes the crop fields more successful and efficient, it can cause dangers to bodies of water downstream such as McFarland Lake. As you can see from the map below, the tile system currently captures water from approximately 50% of the crop land to the east of Interstate 35. These fields that grow corn, soybeans, and oats can be using chemicals for plant growth that could be harmful for vegetation in McFarland Lake. Also, all of the water run off that once stayed on or near the croplands and filtered naturally to ground water or a near by stream no longer does that. The water is all sent to this tile system that carries the water

underneath Interstate 35 where it is dumped into the inlet channel of the lake at a much higher rate.

Although tile systems are very effective for the farmer’s crops, they can be very harmful to the rest of the watershed and could be affecting McFarland Lake directly. The major concern for McFarland park is the velocity at which this water is coming into the lake. Water that once sheet flowed down the landscape and was able to infiltrate naturally is now more concentrated and moving at a higher velocity into McFarland lake and causing erosion. The tile systems are something that will need to be monitored and altered to help keep McFarland Lake a healthy and successful lake.

4.3 Historic Photos I have included aerial photos of McFarland Lake from 1930-2011. These photos are available GIS layer downloads for the public and provide views of how the land has changed over the past 80 years. The photos show that McFarland Lake was constructed sometime between 1930 and 1950. Originally the area was a stream that lead to the South Skunk river. Story County decided they wanted a lake there and put a dam on the northwest side of the lake is to create it. The current topography in the surrounding area shows this general slope towards the South Skunk River and that is where the overflow to the lake currently flows to. There have been a few major development over the years that have changed the McFarland Lake Watershed. Interstate 35 was built in the area around 1970. This caused major topography changes in the area and the need for drainage pipes to lead water under the highway. The Touch-A-Life trails started to appear in the aerial photos around 1980 and the Story County Offices were also built around this time.

Over the years the vegetation has grown more around the lake due to age of the vegetation, as well as the efforts of the Story County Conservation. This has caused the land directly around the lake to become a very dense deciduous tree canopy. Also the installation of tile systems by the agriculture farms start to become visible over the years. Clear paths of wetlands developed where the farms were moving water and unable to plant crops.

1930’s 1950’s

1960’s 1970’s

1980’s 1990’s

2005 2011

McFarland Watershed Historic Photos

1930’s 1950’s

1960’s 1970’s

1980’s 1990’s

2005 2011

McFarland Lake Historic Photos

4.4 Discharge Pipes & Culverts

At McFarland Lake there are both discharge pipes and culverts bringing in water to the lake. Discharge pipes usually cause the most problems for the lake and are bringing in the largest amount of water. Discharge pipes are used when capturing water away from site and discharging it into a body of water. As a result, many things could harm McFarland Lake including pollutants, volumes of water, and high velocity of water. The pipes must be monitored to keep McFarland healthy.

The second type of pipe on site are the culverts. A culvert is used to carry water underneath a paved surface to help avoid sheet flow on the pavement. On site currently, they are used to carry water underneath the sidewalks. Topography is heavily used to help move the water to the start of the culvert. The major cause for concern is where the culvert is dumping the water back onto the surface near the shore line. The outlets of the culverts can be poorly located and can be causing erosion due to high velocity and volumes of water and bring sediment directly into the lake.

At McFarland Park there are three major discharge pipes and 9 culverts that run underneath the Touch-a-Life sidewalk. The two major discharge pipes are located at the start of the major inlets to the lake. They carry water from catchment areas on the opposite sides of Interstate 35 and 180th street. They both have long vegetated channels that carry the water into McFarland Lake. The 10 culverts on site are capturing surface runoff from the surrounding topography and sending the water to the lake through pipes.

4.5 Vegetation Along the Shoreline

The shoreline vegetation at McFarland Lake has a combination of Canopy Trees, shrubs, herbaceous plants, and mowed lawn. During my visits to the lake, I studied what vegetation currently exists on site.

Canopy Trees

American Elm

Basswood

Black Walnut

Burr Oak

Butternut

Eastern Redcedar

Red Elm

Red Oak

Russian Olive

Sandbar Willow

Shagbarck Hickory

Silver MapleSycamore

Canopy Trees within 15’ of Shoreline

On one of my visits to McFarland Lake, I marked with a GPS unit every tree within the first 15 feet of the shoreline that had a trunk diameter larger tan six inches. I was able to mark a total of 173 trees and below is a map of where those trees are located. There is a combination of American Elm, Basswood, Black Walnut, Burr Oak, Butternut, Eastern Redcedar, Red Elm, Russian Olive, Sandbar Willow, Shagbark Hickory, Silver Maple, and Sycamore. The tree quantities chart to the right shows that a majority of the trees are Basswood, Burr Oak, and Eastern Redcedar. The tree sizes varied around the lake as well and my chart for Basswood trunk sizes shows the variability of the trunk sizes of that species and has similar variation to the other species. Again, these were the trees that had a trunk diameter of larger then 6 inches. A majority of the shoreline has a large amount of smaller trees and tree shoots filling the canopy.

Discharge Pipes & Culverts

CulvertsDischarge Pipes

America

n Elm

Bassw

ood

Black W

alnut

Burr O

akButt

ernut

Easte

rn R

edce

dar

Red E

lmRed

Oak

Russia

n Oliv

e

Sand

bar W

illow

Shag

bark

Hick

ory

Silve

r Map

leSy

camor

e010203040506070

Tree Quantities within 15’ of Shoreline

6”-11” 12”-23” 24”-35” 36”-47” 48”-65” Multi-Stem

02468

101214161820

Basswood Trunk Diameter Sizes

Num

ber o

f Tre

es

Trunk Sizes (inches)

Herbaceous Vegetation The majority of the herbaceous layer at McFarland Park has been taken over by Reed Canary Grass. Reed Canary Grass is an invasive species and a major problem all over freshwater ecosystems in Iowa. The grass grows so vigorously that it takes over other competing plants. The Reed Canary Grass problem is something that will need to be addressed in future projects with McFarland Park. There are other natives that still exist on site and include Indian Grass, Big Blue Stem, Cat Tail, etc. There is a lack of emergent vegetation in McFarland Lake because of the presence of Carp in the lake. The carp eat and tear up any emergent vegetation before it has time to get established. Emergent vegetation could provide water quality, soil stabilization, and habitat benefits and is something that needs to be addressed.

4.6 Shoreline Erosion

McFarland Lake Shoreline Erosion Problem Areas

Shoreline erosion is a problem in a few select locations around McFarland Lake. Erosion problems are caused by unstable soils being washed away by water movement. The sediment from the erosion then washes into the lake and settles on the bottom,

Below is a map of where the major erosion problems that need to be addressed currently exist. The area that is the most affected and has the most visible erosion is the southwest corner of the lake. Water comes into the lake through the tile system and during large storms it comes into this area at high speeds, eroding this corner of the lake. Steep banks at the lake’s edge are very visible and show an immediate need for attention.

Another concern the Story County Conservation Group has is erosion at the Touch-a-Life trail that runs around the lake. There is little damage to the path and surrounding soil at this point because of the group’s minor erosion control efforts but they are concerned what will happen to the path if actions aren’t taken to help prevent erosion. This is a problem for the lake because erosion from around the trail can be traveling down slope to the water and filling the lake with sediment. The conservation group has started multiple practices to address erosion issues. Invasive removal has been occurring on the north side of the lake to create a more open and natural look to the landscape and serves a stronger purpose of erosion control. A goal of the conservation group is to get an Oak and Hickory dominated canopy with native grasses in the understory. Prescribed burning and temporary grazing has been used to help stop the spread of invasives. Lastly, chemical application has been used to remove species such as Honeysuckle, Crown Vetch, Sumac, etc. These practices are helpful but also need to be expanded on.

altering the existing ecosystems of the lake. The major problem causing erosion is the lack of vegetation in the understory of the shore edge. The dense tree cover makes erosion preventing vegetation have difficulty growing.

PrarieRestoration

PrarieRestoration

Woodlands

Woodlands

Camping Area

Camping Area Picnic

Area

PicnicAreas

PicnicArea

Oak Savanna Restoration

Inlet/WetlandArea

Inlet/WetlandArea

Open Access to Water

Open Access to Water

Canoe/ Boat Access Points

4.7 Activity Zones This is an activity zone map for McFarland Lake that I created after talking with the Story County Conservation group about how they currently use the site. The different colors of zones represent the different zones as labeled on the map. The different types of zones include woodlands, areas open for water access, inlet/wetland areas, oak savanna restoration, prairie restoration, picnic areas, camping areas, and boat access points. There are two inlet areas that have been designated on site. The main inlet is on the south east edge of the lake and the secondary one is on the south edge of the lake. These areas have drastic topography to guide water into the lake. The area is densely vegetation with herbaceous plants, shrubs, and a dense tree canopy lining the edges. These areas are not meant for people to be walking in but do have bridges across them for people to continue on the Touch-a-Life trail. There are also woodlands, oak savanna restoration areas, and prairie restoration areas on site. The woodlands are in locations where the vegetation under the canopy has been cleared to allow people to move through on trails. The oak savanna restoration

has been put on the north east edge of the lake to maintain a natural vegetation transition from the prairie area. The prairie restoration areas are not at the lakes edge but are a significant feature in the park. They bring in natural vegetation to the park and help filter surface water running off into the lake. There are also two open access areas to the water that contain a couple of canoe/boat access points. One of these areas is located on the northwest corner of the lake where the outlet/overflow point for the lake is. This area includes two access points for boats that are primarily used by the DNR and the Story County Conservation group. There is another open access area to the water on the south edge of the area closest to the Story County Conservation offices. This area consists of designated picnic areas and a canoe access point for the conservation group and the classes they hold in the park. There are also designated camping/picnic areas on site. The two primary camping areas are located on the north and northwest eges of the lake. Both Camping areas are in close proximity to the lakes edge but are also close to the north woodlands where trails are available. There are also two large picnic areas available that have large tables and are

4.8 Inlet Channels There are 2 major inlets to the lake where tile systems release into McFarland Lake. The major inlet is at the far southwest corner of the lake and has a long wetland ecosystem that connects it to the lake. The second inlet is slightly smaller and is located on the southern edge of the lake close to the Story County Offices. This wetland has less herbaceous plants and is dominated by a dense canopy.

Major Inlet

Second Inlet

5.1 Agriculture Watershed

5. Recommendations

With the surrounding land in the watershed being privately owned, it is difficult for the Story County Conservation to implement any environmental changes. The most important thing they can do is educate the community and the property owners about what needs to be done to keep McFarland Lake healthy and around for a long time. In these meetings, they can describe processes to reduce water runoff, cover crops, and buffer strips. The public needs to be aware of the damages that are occurring, what they need to do to resolve them, and the costs and benefits of these actions.

Reducing Water Runoff Reducing water runoff is a key factor that needs to happen in the McFarland watershed. One way property owners can solve this is by installing water retention ponds on their property. Although this takes away cropland that they could profit from, it is a way they can capture water off their land that may be polluted from chemicals. This gives the water a chance to stay away from the rest of the watershed and be filtered and infiltrated on site. Another practice the property owners could utilize is the installation of bioswales along their property lines that can carry water to larger water storage systems. Bioswales could filtrate and run the water off of their site to a location meant for storing and treating polluted water, keeping it away from McFarland Lake. Most importantly, property owners need to be made aware of where the water from their land is traveling to and what they are able to do to help improve the overall watershed.

Cover Crops Cover crops are crops that are planted with the purpose of improving and maintaining the ecosystem. For the ecosystem, cover crops enhance biodiversity, increase soil infiltration, and create wildlife habitat. These are all benefits that would not only help the property owner’s land, but also the whole watershed and McFarland Lake. Cover crops also have an effect on the farmer’s land as well. They reduce erosion, improve soil quality through improved porosity, add soil organic matter, improve the water holding capacity, add beneficial microbes, retain nutrients that would otherwise be lost, add nitrogen through fixation, combat weeds, and break disease cycles. Cover crop species include grasses, legumes, brassicas, and other non-legume broad leaves. Below is an example of what a possible cover crop installation could look like.

Cover Crop Example

http://fromfieldtofield.com/2011/12/05/turnip-cover-crops/

designated along the path that connects the two larger picnic areas.

Buffer Strips Buffer strips are small strips of land that have strong biodiversity, designed to intercept pollutants and manage environmental concerns. Informing property owners of this practice can help mitigate the movement of sediment, nutrients, and pesticides from the agricultural fields. This is a less costly option for the farmers because the strips take up less land but act as a good buffer between their property and the rest of the watershed. Some benefits of buffer strips include soil erosion control, improved soil quality, enhanced fish and wildife habitat, flood reduction, and biodiversity conservation.

5.2 McFarland Park

When looking at the shoreline vegetation for McFarland Lake, you will see mainly dense tree cover and the herbaceous layer being dominated by reed canary grass. This has created a non-diverse plant palate and lacks the possibilities a diverse ecosystem can carry. My goal for McFarland Lake is to focus on improving its herbaceous layer with the removal of Reed Canary Grass and the installation of plants from the Wet Mesic Community and the Mesic Community.

Desired Herbaceous Layer Plant List

Andropogon gerardiiCarex bicknelliiCarex inopsJuncus interiorKoeleria macranthaLiatris pycnostachyaPanicum virgatumPascopytrum smithiiRatibida columniferaSchizachyrium scopariumSorghastrum nutansSporobolus heterolepis

Big Bluestem Bicknell’s SedgeSun SedgeInland RushJune GrassPrairie Blazing StarSwitchgrassWestern wheatgrassLong-headed ConeflowerLittle BluestemIndian GrassPrairie Dropseed

Warm SeasonCool SeasonCool SeasonCool SeasonCool SeasonWarm SeasonWarm SeasonCool SeasonCool SeasonWarm SeasonWarm SeasonWarm Season

2’ - 5’18” - 30”6”-12”2’ - 3’12” - 24”2’ - 4’3’ - 5’1’ - 3’1’ - 3’1’ - 3’3’ - 8’2’ - 3’

4106276524549

Scientific Name Common Name Season Height C of C

I created a desired herbaceous layer plant list shown in the chart below. These are all plants that can survive in the area from the high water level line and above the saturation limit. By combining the two lists, I was able to create one that had a mix of warm and cold season plants, a range of plant heights, and a range of the level of Coefficient of Conservation (C of C). The C of C ranks plants on their importants of being conserved in the area with 10 being the highest and 1 being the lowest.

Some of the benefits of increasing the biodiversity of the herbaceous layer at the shoreline include sediment reduction, nutrient reduction, natural aesthetics, infrastructure protection (walking trails), and wildlife habitat. Vegetation in this zone would help stabilize the soil and prevent erosion from wave action and water runoff. Habitat would be increased for insects and habitats. These habitats could provide environmental benefits for the lake as well as being an attraction at the lake’s edge and bring people closer to the water. Most importantly, it would improve the natural aesthetics of the lake. The natural vegetation around the lake has been taken over by Reed Canary Grass over the years and has lost the natural beauty of mixed colors, heights, and advantages. By improving this plant community, McFarland Lake can be healthier overall, as well as a more beautiful attraction for the people of Iowa. On the next page is a diagram of what the plant and habitat communities could possibly be gaining if this project was installed.

Shoreline Vegetationhttp://www.spencenursery.com/Index/lake_edge_enhancement_system.php

Sedg

e M

edow

Com

mun

ity

Touc

h-A

-Life

Tra

il

Des

ired

Shor

elin

e H

abita

t

Exam

ple

of p

oten

tial

colo

rs a

nd a

esth

etic

s tha

t co

uld

be im

plem

ente

d al

ong

shor

elin

e.Po

tent

ial W

ildlif

e Ex

ampl

es

Ben

efits

-Sed

imen

t red

uctio

n in

the

lake

-Aes

thet

ic b

eaut

y th

roug

h co

lors

and

text

ures

-Nut

rient

redu

ctio

n in

the

lake

-Div

ers w

ildlif

e ha

bita

t

Sedg

e M

edow

Com

mun

ity

At the two major inlets to McFarland Lake, the areas have become silted in and overtaken by Reed Canary Grass. The picture below is an example of what the inlet currently looks like today. This is a problem because Reed Canary Grass is an invasive species and dominates the environment that native plants could thrive in. The native plants could treat water pollutants and add a much stronger visual appeal to the park. Moving forward, the Story County Conservation needs to take action to control the Reed Canary Grass and restore the natural wetland flora of the area, in order to enjoy the benefits that come from it.

Inlet Wetland Restoration

Reed Canary Grass is a grass found in wetlands , including marshes, wet prairies, wet meadows, stream banks, and swales. There are a couple of ways that this problem can be managed at McFarland Lake. The first would be to remove the plantings using a herbicide that is appropriate for aquatic habitats. This is probably the most cost effective and feasible method in an area where the trees are spaced too closely to get equipment to the water’s edge. There is also the possibility of using controlled fires in the large stands of Canary Grass in the inlets. This is a much riskier application because you would not want to affect the other vegetation around the lake that shouldn’t be burnt. Once the Reed Canary Grass has been removed from the inlets, it will be up to the Story County Conservation to control the re-spread of the species through fires, herbicides, and hand picking small patches. After the removal of the invasives that have taken over the inlets, the goal will be to restore the natural wetland flora of Iowa. The plants can vary greatly from what can be planted, but a good

mix of height, color, and benefits will make the wetland more successful. Some plants that could be considered are Giant Bur Reed, Common Cattail, Water Plantain, Arrowhead, Water Smartweed, etc. The variety of vegetation will create many benefits for the wetlands, McFarland Lake, and the Watershed.

There are many benefits to wetland restoration at McFarland Park. First is flood mitigation, as it would help lower the speed and quantity of water runoff through it’s own ability to store water. Second, the wetlands would improve water quality of the lake because the native plants will be able to use and filtrate a lot of the harmful pollutants in the water entering the lake. Third, it could provide habitat for wildlife that currently has no natural place to live in the park. Lastly, the restored wetlands would become much more aesthetically pleasing through its rich biodiversity and could act as an area to teach the students that visit the park.

Current Inlet Conditions

http://arcticlcc.org/projects/landscape/changing-climate-biomes

Proposed Wetland

The current shoreline erosion in locations pointed out earlier in this report need to be addressed to keep McFarland Lake healthy. The erosion is bringing sediment into the lake and destroying habitats within the lake. In addition, the park is loosing land area around the lake. The troubles with dealing with this problem at McFarland Lake because of the amount of tree cover around the lake. The tree cover is so dense that it makes it impossible to get the equipment needed for larger projects to the lake shore. So when looking at what can be done at McFarland Lake, it will be important to consider methods of erosion control that can be installed by hand. The primary method of erosion of control I am suggesting is the Toe-Wood Saw Mat.

Shoreline Erosion

The Toe-Wood-Saw Mat is a system of creating a bench of debris at the shoreline to help stabilize the shore by absorbing the force of the water movement. Above is section profile of the Wood-Toe Saw Mat. The construction process starts with clearing the shelf to provide room for the proposed shelf coming in. Then, the bench is placed and consists of logs, branches, brush, roots, and all things that are moveable by hand. The bench will then be filled with soil to help stabilize the material. Then, the bench is covered with a layer of live cutting and topped with a layer of sod mats. This will give the structure a nice vegetated look on top and a strong sturdy bottom to protect the soil. The structure will eventually break down over years, but by then the soil and plants behind will have been able to settle enough to where it can start protecting itself. Below is an image that shows a shoreline where erosion is occurring and this practice could be constructed.

Eroding Shoreline

The outlets for the culverts and discharge pipes are often poorly located. With distances around 10 feet from the shoreline, this leaves excess land area that the water needs to be running down and causes erosion. Below is an image of a culvert outlet point and the gully it has began to create on its path to the lake.

Culvert & Discharge Pipe Outlets

Current Pipe Outlet Location

The way I propose to fix this problem is to extend the pipes down the hill and let the outlet point be right next to the water’s edge. This will prevent land from being eroded up hill that would be otherwise. At the new outlet point locations, rock and small rip-rap may be placed to take the force of this initial discharge of water from the pipe before entering the lake. This is a very simple yet necessary fix to a problem at McFarland Lake.

Toe-Wood-Saw Mat Section Profile

http://files.dnr.state.mn.us/publications/waters/toe_woodsod_mat_dec2010.pdf

180th st

Handicap Accessible Dock

New RecreationalDock

Canoe Access Point

Pedestrian Use and Circulation

Pedestrian use and circulation need to be a major focus moving forward with the success of McFarland Park. McFarland Lake is a major attraction in Story County and improving pedestrians’ experience at the park will encourage them to come back and bring new people. Currently the park has designated places for a dock and canoe access on the lake but many of these locations need to be updated or improved for pedestrians to be aware of them and to want to use them. The Story County Conservation group has expressed interest in fixing some of these issues in the upcoming years, and my recommendations are

focused on giving examples and details on how they can address their concerns. With the Touch-a-Life trail around the lake and park recently attended to and repaired, my recommendations are focused on the lake’s edge and getting people engaged with the water. The lake’s current dock needs to be fixed and redesigned to become handicap accessible, new docks need to be added to give new locations for fishing, and a permanent natural canoe access needs to be established. The areas I recommend for these changes are marked below and the following pages provide more detail.

Dispersion

http://www.access-board.gov/attachments/article/590/fishing.pdf

Pedestrian Use and Circulation:Handicap Accessible Dock

Current Situation

Character Images

McFarland Park is in need of a ADA approved handicap accessible dock. The only floating structure that currently exists on the lake is pictured to the right and has become run down over the years. There is steep slope with a large bump to get up to the dock and the space and slope on the wood structure itself does not comply with ADA standards. Fixing or redesigning the current dock to be the new ADA Accessible dock makes sense because it is in a good spot in relation to the Story County offices and would be the easiest place for handicapped access. A gangway, or a the walkway linking land with a floating structure, needs to be established on site. ADA requires a maximum slope of 8.33% on gangways that provide a smooth transition from the land to the platform. Currently the sidewalk has shifted by the dock creating a step up that does not meet ADA standards. A gangway would need to be established to make an ADA certified fishing pier. The railings of the dock will also need to be adjusted to meet ADA standards. It is required that 25% of the railings on the dock have to have a maximum height of 34” which will allow a person in a wheelchair to fish over it. This does not currently exist on site. Dispersion can be added to help meet these guidelines (pictured to the right). Dispersion is spreading out the 34” railings around the dock platform to give handicapped people multiple choices of where to fish from. A 2” vertical edge protector is also required in locations of railings

and guardrails to prevent wheelchairs from slipping off the platform.

Clear floor or ground space also needs to be provided as it is currently not on site. A space of 30”x48” must be provided where there is a 34” railing for a wheelchair. A 60” turning space or a T-shaped space must be provided to give room for a wheelchair or mobility device to turn around and access the rest of the dock.

Pedestrian Use and Circulation:Recreational Docks

Character Images

I am also recommending that additional docks be added on the lake at McFarland Park for recreational use. Currently there is only one dock for use and the addition of multiple docks in other spots around the lake will attract other anglers to explore the area. I pointed out on the aerial image 2 potential locations I would recommend to add new docks. This would provide different water edge conditions that other areas could be considered for the addition of more docks. The addition of new docks around the lake will help attract more anglers to the park. The docks help get anglers off the shoreline and increase the surface area of the lake that they are able to fish. The lack of docks right now force a lot of anglers to walk through vegetation along the shoreline to get to new locations to fish. This is causing erosion and difficulty for plants to survive under the increased foot traffic. Placing docks in multiple locations around the lake provides the Story County Conservation group the opportunity to focus their efforts of improving lake edge conditions where the new docks are present and the most activity exists. Another opportunity new docks would offer is the potential to use them more for educational purposes in the park. The docks will allow better access to the water and improve the ability to study emergent vegetation around the shoreline. This is where unique dock design options can be explored in the future to be integrated directly with the

shoreline vegetation. In the character images below, I provided a couple of examples of dock designs that let vegetation to be incorporated directly with it. This would be very beneficial because it allows both children and adult to study different vegetations and creatures they can’t reach standing along the shore.

Finally, new recreational docks will provide more places for people to get canoes in an out of the water separate from the designated boat access points. This allows McFarland Park to be a more desired location for people in Story County looking for a place to canoe. The docks would act as a sturdy surface that could be used at multiple locations around the lake and would be safe for people to get out of their boat.

Potential Locations of New Recreational Docks

Pedestrian Use and Circulation:Canoe Access Point

Character Images

Current Situation

The Story County Conservation group has expressed strong interest in a new canoe access point as an element for the development of McFarland Park. Canoeing to the water needs to be addressed. The group has identified two destinations the lake as boat access locations, but neither are easy or safe for people to get in and out of the water. I recommend that the conservation group considers creating a more structured and permanent solution by converting the boat access currently on the southwest side of the lake through use of either a natural look or a pre-fabricated dock element. I believe a “natural” appearance for a boat access at McFarland lake would compliment the efforts of Story County to establish natural lake shore vegetation and elements around the rest of the park. A “natural” appearance would consist of native stones, vegetation, and wood to create a safe and structured experience. Below are examples of what other lakes have done to create this type of access to the water. Wood creates a structured and clean appearance for the access, while stone creates a rough appearance that might replicate other landscape elements in Iowa. Vegetation in and around the boat access could be used to help stabilize the soil, given the amount of foot traffic in that area, and create a visual focal point from the water at the boat access.

that are designed for canoe access. This would be best implemented in locations discussed earlier in this report where new recreational docks would be located. There are benefits of pre-fabricated dock addition. They are very easy to install and implement. They are also easier for boaters to use. Many pre-fabricated canoe docks are ADA accessible and could be added to handicap accessible docks discussed earlier in this report. Although the pre-fabricated dock doesn’t provide the visual appeal that the natural boat access potentially could, it can be more functional and affordable in implement.

Another option to consider is the implementation of pre-fabricated dock extensions

When I was looking for a project to do for my independent study, I wanted a project that would be useful for me and whoever I completed it for. I feel that for this project, I provided a useful document for the Story County Conservation group but more importantly, it helped me gain knowledge on lake ecology as well as help me grow as Landscape Architect student. I would have been able to come up with a successful project without the help of all the people that contributed to my project over the semester.

First I would like to thank Carol William, Ryan Wiemold, Jerry Keys, and everyone from the Story County Conservation group that helped develop the idea for this project. I truly appreciate you bringing me and, telling me about McFarland Lake, and guiding me along through this project. Second, I would like to thank Andy Otting and Ben Dodd from the Iowa DNR. I enjoyed my visit with both of you and loved the opportunity to come into your office to see what you do for the DNR and to hear about the Lakes of Central Iowa. Thank you to Robin McNeely for the GIS assistance throughout the project and the guidance with GPS equipment and thank you to Bruce Carlson for the initial help in developing the idea for the project and providing his guidance.

Most importantly, thank you to Mimi Wagner for agreeing to do this project with me. You challenged me and taught me so much throughout this semester and they are all things I will use later in my career after school. Your knowledge and commitment to my development is something I will always remember and I look forward to getting to work together again.

Acknowledgments