A Water Quality Characterization and Urban
Development Assessment of Timber Lake
Kate Skaggs
Seniors Honors Project
Submitted in partial fulfillment of the graduation requirements
of the Westover Honors Program
Westover Honors Program
April 28, 2006
_________________________________________
Dr. Thomas Shahady, Committee Chair
_________________________________________
Dr. Nancy Cowden, Westover Committee Member
_________________________________________
Dr. David Perault, Committee Member
Abstract
I examined the water quality of Timber Lake and three streams entering above the lake:
Buffalo, Waterlick, and Brown. Timber Lake is located in Campbell County, Virginia
outside of Lynchburg, Virginia. Before monitoring began, construction permits were
granted to an independent corporation to build townhomes at the source of Waterlick
Creek. I hypothesized that Waterlick Creek, in an undeveloped portion of the watershed,
would have the best water quality, while each of the two other streams would have good
to moderate water quality. Biological assessment of Buffalo, Waterlick, and Brown
streams began in March of 2005. The assessment included fish shocking,
macroinvertebrate collection, and taking physical and chemical parameters for each
stream. Timber Lake’s watershed was additionally characterized for landuse using an
aerial photograph digitized into ArcView 3.3. Impairments from shoreline development
and development along each of the three streams have impacted Timber Lake. Although
still being controlled by in-lake function, increased total phosphorus levels after a rain
event illustrate the lake is being strongly influenced by riverine inputs. A high
percentage of Daphnia out of total zooplankton is preventing eutrophic lake signs from
being seen by keeping chlorophyll-a levels low. Each of the streams has good water
quality and Timber Lake is mesotrophic. Although the overall water quality of the three
streams and Timber Lake is good, each is more impacted than expected. Monitoring of
Timber Lake’s watershed is ongoing.
2
Introduction
Landuse
Past studies find a negative significant correlation between increases in development and
water quality of streams and lakes within the watershed (Bennett et al. 2001, Eilers et al.
2001, Jennings et al. 2003, Sudhira 2000). The land within a watershed provides
important resources for maintaining water quality; such as woody debris utilized as
buffers for runoff, nutrient and sediment control, and treatment of toxins. Increasing
watershed and shoreline development amplifies sediment and nutrient inputs into streams
and lakes (Jennings et al. 2003, Keen 1997, Lindauer 2001, Petts 1988). Nutrients such
as nitrogen and phosphorus are essential to the production in lakes and streams, however,
overloading of these nutrients causes rapid eutrophication of lakes and alters entire
freshwater ecosystems (Sudhira 2000, Bennett et al. 2001).
Because nitrogen is found in large quantities in the atmosphere, phosphorus is usually the
primary limiting factor within a lake. If too much phosphorus enters into a lake,
overproduction will take place resulting in the accelerated eutrophication of the lake
(Sudhira 2000). Excess phosphorus produces algal blooms that have the potential to
deteriorate the quality of the lake by utilizing the nutrients within the lake and
diminishing the amount of sunlight entering the water (Dodson et al. 1998, Dodson 2005,
Closs et al. 2004).
Changes in land management of the watershed initiate phosphorus loss from soil by
means of construction and development or clearing land for agriculture (Bennett et al.
3
2001, Petts 1988). More development reduces the amount of woody debris that could
potentially filter and slow runoff from impervious surfaces (Christensen et al. 1996).
Increases in sediment flow will relatively increase the flow rate of nutrients, such as
phosphorus and nitrogen, into the lake’s watershed. In almost all cases, phosphorus is the
limiting nutrient in lakes and reservoirs because it is less abundant than nitrogen
(Carpenter et al. 1998). When lake phosphorus inputs increase to where phosphorus is no
longer limiting, production relatively increases leading to algal blooms (Carpenter et al.
1998, Kung and Ying 1990). Algal blooms use up lake resources that would otherwise
be distributed throughout the lake, such as sunlight and nitrogen. Further, urban
construction has the possibility of altering entire food chains within the lake’s watershed.
Impervious surfaces greatly increase the rate at which runoff from rain events enters into
a watershed. Faster rates of flow of sediments and nutrients into a lake cause decreases
in water quality. High flow rates lead to high levels of sediment flow, high levels of
phosphorus and nutrients entering the lake, and runoff having less time and opportunity
to be filtered. Buffers such as coarse woody debris help to raise pH levels of runoff and
reduce overall pollution found in rivers (Christensen 1996).
The energy source for the food chain in streams comes from the decay of coarse woody
debris (Christensen 1996). When the energy source is lost, repercussions can be seen
within streams. Organisms in a stream require a specific amount of energy, light, and
nutrients to survive. If any of these are disturbed, the food chain of the stream will
eventually lead to a reduction of water quality within the streams and lake.
4
Trophic Status
In a healthy, oligotrophic lake, the energy production of the lake is controlled by
biological factors (Dodson et al. 1998). There is little organic matter and turbidity is low.
In an oligotrophic state, nutrient inputs create a steady state where transparency,
chlorophyll-a, and total phosphorus levels within the lake create a balanced environment
(Dodson et al. 1998). In this environment, phosphorus levels limit primary production to
a healthy level. A healthy level is determined by an amount of algal production that
zooplankton consume efficiently. Planktivores feed on zooplankton, and consequently
piscivores feed on planktivores (Dodson et al. 1998).
Each lake has its own level of resilience. Resilience is the ability of the lake to withstand
increased levels of stress inputs such as phosphorus (Dodson et al. 1998). When the lake
exceeds its resilience level it changes states. For example, an oligotrophic lake that
surpasses its resilience level from increased nutrients changes to a eutrophic state. Lakes
can recover from modest amount of phosphorus inputs; however, if enough phosphorus is
stressed upon a lake’s ecosystem, the lake will stabilize at a eutrophic state (Dodson et. al
1998). A eutrophic lake is not controlled by biotic factors, but rather by the nutrient
inputs. When a lake becomes eutrophic the primary production dramatically increases
(Dodson et al. 1998). Large levels of primary production overwhelm zooplankton and
limit their consumption. The effect of excess production results in algal blooms and
oxygen used for the decay of algae rather than by fish and other lake organisms (Dodson
5
et al. 1998). This lake is controlled by phosphorus and other nutrient levels that enter the
lake, rather than by the consumption of algae by zooplankton.
To make characterizing a lake’s trophic status easier for comparison, trophic state indices
exist to compare specific water quality indicators. The Carlson trophic state index (TSI)
is used to characterize the trophic status of lakes (Carlson 1977). The Carlson index uses
the Secchi depth, total phosphorus, and chlorophyll-a levels (Carlson 1977). Each
parameter is given an individual TSI value and is found with the following equations:
Total phosphorus TSI (TSIP) = 14.42*[ln(TP average)] + 4.15
[1]
Chlorophyll-a TSI (TSIC) = 9.81*[ln(Chlorophyll-a average)] + 30.6
[2]
Secchi disk TSI (TSIS) = 60 – (14.41*[ln(Secchi average)])
[3]
Based on the data collected for these three indicators, a number between 30 and 80 is
assigned to the lake to describe that lake’s specific trophic state between oligotrophic,
mesotrophic, eutrophic, and hypereutrophic. A TSI value of less than 30 is an
oligotrophic lake, a value of 40-50 is a mesotrophic lake, 50-60 represents a slightly
eutrophic lake, 60-70 is eutrophic, and a lake with a TSI value of 70-80 is considered
hypereutrophic (Carlson 1977). Lower levels of TP and chlorophyll-a, and deeper Secchi
depths produce oligotrophic lakes while higher levels of TP, chlorophyll-a, and Secchi
depths produce more eutrophic lakes (Carlson 1977).
6
Eutrophication is caused by continuously increasing amounts of nutrients added to a
lake’s ecosystem (Dodson 2005). Higher nutrient and sediment flows into lakes are
usually the result of increased development, erosion from construction sites, and inputs
from fertilizers for lawns or agricultural use (Dodson 2005). An example of a eutrophic
lake can be seen in College Lake in Lynchburg, Virginia. College Lake is no longer
controlled by biotic factors but instead by abiotic, solely by the sediment and nutrient
inputs into the lake. Attempts were made to reverse the effects of eutrophication in the
Great Lakes and it was found that the most effective methods involved the management
of point and non-point sources of phosphorus loading (Medine and Lamarra 1984). It
was also found that through the remediation process, as water quality objectives became
more stringent, the cost of remediation increased dramatically (Medine and Lamarra
1984). In addition, the amount of shoreline development and development within the
lake’s watershed made it complicated to evaluate and manage non-point source pollution
of phosphorus and other nutrients (Medine, 1984). Relating to Timber Lake, the most
effective way to prevent eutrophication would be to regulate point source and non-point
source pollution. Regulating the construction on the Waterlick site will be imperative to
preserving and improving the water quality of Timber Lake.
History of Timber Lake
Timber Lake was originally dammed in 1926. The Timber Lake area initially served as
an area of recreation and vacation, including only a few log cabins, a main tavern used
7
for dances and large gatherings. Currently what were once summer homes have been
converted into year-round houses. Increases in residential development showed
noticeable effects on the lake beginning around 1990. An unpublished study done by two
Radford University professors in 1991 found that the amount of precipitation ending up
in the lake had increased almost 100 percent from the time the dam was built to 1990.
The amount of shoreline development and other urban development within the lake’s
watershed dramatically increased the percentage of impervious surfaces increasing the
rate of runoff entering the lake. In 1993 Timber Lake had a noticeable vegetation and
sediment problem. Coves around the lake were filling in and the option to dredge the
lake was being considered as a course of action. In the summer of 1995 a torrential rain
storm dropped enough precipitation into the lake within a short period of time to cause
the dam to break (Berghom 2005a, 2005b). To repair the lake, Timber Lake was dredged
and the dam was rebuilt; Timber Lake is now a relatively young lake and not the same
lake that has been present since 1926.
In 1999 Timber Lake’s watershed was established as a watershed improvement district
(WID). Declaring Timber Lake as a WID gives homeowners within the watershed the
power to establish a governing body with jurisdiction over the watershed. The governing
body is made up of the directors from the soil and water conservation district
encompassing the improvement district. The directors appoint three landowners within
the WID as trustees to the governing body. The trustees carry out administrative duties
with powers delegated to them by the directors. A WID has all the powers of the soil and
water conservation district. These powers include the power to tax landowners within the
8
improvement district. The dredging and rebuilding of Timber Lake required a large
amount of money that was offered by residents of the community surrounding Timber
Lake. Maintaining the lake also involves large sums of money. With the designation of
Timber Lake as a WID, a homeowners’ association has the ability to tax residents of the
lake. This tax ensures that there are funds to maintain Timber Lake and preserve the
lake.
The Braxton Park development project is a proposal for 200 townhomes and four
commercial properties. Braxton has agreed to follow Virginia’s Best Management
Practices including four storm water management ponds to provide sustainability for 10year storm water capability. In addition, Braxton will invest $20,000 towards the
improvement of Timber Lake. The area encompassing this development site represents
four percent of the total vacant acreage in the Timber Lake watershed. Finally, Braxton
has offered to help with the cost of adding a sewage pumping station to the property,
located along Waterlick stream to pump sewage to Lynchburg’s sewage system
(Campbell County Board of Supervisors Meeting 2005).
This study examines the water quality of Timber Lake and three streams entering into the
lake, Buffalo, Waterlick, and Brown outside of Lynchburg, Virginia. If the water quality
of the three streams is healthy, then I predict that the water quality of Timber Lake will
be representatively healthy as well. I hypothesize that Waterlick Creek, in an
undeveloped portion of the watershed will have the best water quality. I expect that the
water quality of Timber Lake will be good. Additionally, if urban development occurs at
9
the headwaters of the streams then I predict decreased water quality of the streams and
lake. The quality will decrease because nutrient and sediment levels will rise with a
reduced buffer to filter runoff. If the streams are polluted then the lake’s water quality
will be relatively polluted as well.
Methods
Stream Water Quality
Buffalo, Waterlick, and Brown Creek water quality was analyzed by using a YSI probe
for dissolved oxygen, temperature, conductivity, and pH. Using standard analysis
methods, total phosphorus samples were collected from each stream. Fish shocking,
macroinvertabrate collection and identification, and Ephemeroptera Plecoptera
Trichoptera (EPT), (Appendix C), tests were used to analyze the biological water quality
of the streams. Macroinvertebrates were collected using a Hess sampler. Three samples
were taken at three points along each stream. Each sample site was spaced
approximately 8 m apart. Nine macroinvertebrate samples were collected from Waterlick
stream. After each sample was identified and counted, the data were analyzed for FBI
(Appendix A), EPT, species richness (Appendix B), and PMA (Appendix D). Four
macroinvertebrate samples were collected from Buffalo stream. Samples from Waterlick
and Buffalo streams were identified, counted, and analyzed identically using Family
Biotic Index (FBI) (Hilsenhoff 1988, Appendix A), EPT test (Lenat 1988, Appendix B),
species richness (Plafkin et al. 1989, Appendix C), and Percent Model Affinity (PMA)
10
(Novak and Bode 1992, Appendix D). Macroinvertebrates were identified using Voshell
(2002).
Nine samples were collected along Waterlick Creek, while three samples were collected
along Buffalo and Brown Creeks. To show that three macroinvertebrate samples are
sufficient to accurately characterize the water quality of a stream, the mean total number
of macroinvertebrates and the mean species richness were compared to all possible three
sample collections along Waterlick Creek. Using the nine samples collected from
Waterlick, there are 27 possible three sample collections. The mean total number of
macroinvertebrates and mean species richness were found for each 27 possible sample
collections. The standard deviation for the mean total number of macroinvertebrates and
mean species richness for the nine samples was applied to the possible 27, three sample
collections. One-hundred percent of the mean total number species and mean species
richness found for the 27 possible samples were within one standard deviation from the
nine samples. These data illustrate that any three sample combination along Waterlick
Creek would be sufficient to characterize accurately stream water quality based on
macroinvertebrate sampling.
Lake Water Quality
Timber Lake was sampled once on June 17, 2005 and once on July 26, 2005. These two
dates compare early summer lake productivity to late summer productivity. On each
sampling date Secchi depths, physical data using Hydrolab and a Self-Contained Under
Fluorescence Apparatus (SCUFA) equipment, and zooplankton samples were taken.
11
Secchi depth readings were taken at three sample site locations on Timber Lake (Figure
1). One sample site was at the dam, the second sample site where Brown and Waterlick
Creeks enter the lake, and third at the entrance of Buffalo Creek entering the lake. The
Secchi depth taken on June 17 at the Brown/Waterlick sample site reached the bottom of
the lake. Secchi depth readings were taken further away from shore on July 26 to avoid
reaching to bottom.
12
Brown/Waterlick
Sample Site – June 17
Brown/Waterlick
Sample Site – July 26
Buffalo Sample Site
Dam Sample Site
Figure 1. – Aerial photograph of Timber Lake and designated sampling sites for June 17
and July 26.
13
A Hydrolab was used to measure dissolved oxygen, pH, conductivity, temperature, and
ORP profiles. SCUFA measured chlorophyll-a profiles in Timber Lake. Water samples
were taken at the dam and at the entrance of Buffalo creek into Timber Lake and at the
convergence of Waterlick and Brown streams entrances into Timber Lake. At each
sampling, six water samples were taken; two samples at each sample site at surface and 3
meters. On June 17 water samples were collected from 5 m rather than 3 m. By human
error, on July 26 water samples were collected from 3 m. The water samples were
immediately frozen and preserved for total phosphorus analysis. Zooplankton samples
were collected once on each sampling date at the dam sample site using a 154 µm
Wisconsin net.
The trophic state index of Timber Lake was determined using the Carlson Trophic State
Index (Carlson 1977). The total phosphorus was analyzed using PhospVer 3 with acid
persulfate digestion. The total phosphorus samples were digested with ammonium
persulfate. A Genesys spectrometer was used for comparison to a standard curve.
Percent Daphnia was calculated by pooling two zooplankton samples from June 17, 2005
and July 26, 2005. On June 17, 2005, all zooplankton were identified. On July 26, 2005
only Daphnia were identified. Zooplankton data was pooled to illustrate Daphnia
percentage throughout summer.
14
Watershed Analysis
An aerial photograph from of the Timber Lake watershed was used to digitize land use
within the lake’s watershed. Timber Lake’s watershed land use was analyzed with
ArcView 3.3, GIS. Eight points within the Timber Lake watershed were found using
GPS. These points were used to georeference the aerial photograph. The aerial
photograph was then digitized into ArcView 3.3 using heads-up digitizing. Land use was
determined by visually assessing the aerial photograph and drawing distinctions between
different uses of the watershed in ArcView 3.3. The watershed was characterized using
seven land use categories: forested, forested residential, open residential, grass, bare
ground, water, and urban.
Results
Timberlake Water Quality
Secchi depths were very good for a lake of this size and drainage area (Table 1). In the
other portions of the reservoir Secchi readings reached the bottom. Secchi depths
produced a TSI of 41.9, classifying this lake as mesotrophic. On June 17 there were clear
skies and no rain 24 hours prior to sampling. At the dam on June 17, water was
extremely clear and resulted in a Secchi depth of 3.5 m. Brown/Waterlick sample site
had a Secchi depth of 1.5 m, hitting the bottom of the lake. On July 26 the weather was
15
partly cloudy. A rain event occurred the night prior to sampling. The Secchi depth
recorded at the dam site on July 26 was 0.75 m less than the depth on June 17.
16
Table 1. – Secchi depths and calculated TSI from the three sample sites on Timber Lake
on June 17, 2005 and July 26, 2005.
Sample site
Dam
6/17/05
TSI
Secchi (m)
3.5
42
7/26/05
TSI
Secchi (m)
2.75
45
Brown/Waterlick
1.5
54
2.65
46
Buffalo
3
44
2
50
17
Dissolved oxygen levels are highest at the surface and slowly decrease until
approximately 0.5 m at all sites (Figure 2). Surface dissolved oxygen readings ranged
between 9 mg/L at the Buffalo Creek sampling site to above 13 mg/L at the
Brown/Waterlick Creek sampling site. At a depth of approximately 0.90 m a reading of
13 mg/L was taken at Buffalo Creek sample site. Between 1 m and 1.34 m DO levels
increase with depth at all sample sites. Between 0.5 m and 1.5 m there is an increase in
oxygen that is very slight at the Dam site. This increase is much higher at stream sites
and more pronounced at the Buffalo site. At 1.5 m, on July 26, Buffalo and
Brown/Waterlick sample sites reach their highest DO levels. The Brown site has a DO
level of approximately 13 mg/L and Brown/Waterlick has a DO level of approximately
12 mg/L. The Dam sample site slightly decreases at 1.5 m to just below 10 mg/L. Dam
site reaches a maximum DO level at 2.5 m before dropping dramatically to about 1 mg/L
at 5 m. This overall trend is noticeably the same on June 17 but is not as defined.
Maximum DO levels at the dam site are just above 10 mg/L. Brown/Waterlick site has
the higher DO level of the two stream sites at 9 mg/L. Changes in DO levels at all
samples sites are more gradual and are less extreme on June 17. No anoxic DO levels
were found at any of the sample sites.
18
Timber Lake DO Profile for June 17, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
DO (mg/L)
0
2
Dam
4
Brow n/Waterlick
Buffalo
6
8
10
12
14
Timber Lake DO Profile for July 26, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0
2
DO (mg/L)
4
Dam
Brow n/Waterlick
Buffalo
6
8
10
12
14
Figure 2. – Dissolved oxygen profiles for Timber Lake on June 17, 2005 and July 26,
2005 from samples taken at the Dam sample site, Brown/Waterlick, and Buffalo sample
sites.
19
Temperature profiles at all sample sites in June and July are very similar (Figure 3). A
difference in temperature profiles between the dam and stream samples site is more
noticeable in June than July. July temperatures at all sites are warmer compared to June.
Thermoclines for all sites occur between 1 m and 1.5 m. Stream sample site temperature
profiles on June 17 and July 26 are slightly more gradual and warmer than at the dam
site. In July the Buffalo site reached 33 degrees Celsius and the dam site in July reached
32 degrees Celsius. The greatest increase of DO at Buffalo and Brown/Waterlick’s
sample sites occurs at their thermoclines for June and July.
20
Timber Lake Temperature Profile on June 17, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0
Dam
Temperature (C)
5
Brow n/Waterlick
10
Buffalo
15
20
25
30
35
Timber Lake Temperature Profiles for July 26, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0
Temperature (C)
5
10
Dam
Brow n/Waterlick
Buffalo
15
20
25
30
35
Figure 3. – Temperature profiles for Timber Lake on June 17, 2005 and July 26, 2005 at
the Dam, Brown/Waterlick, and Buffalo sample sites.
21
Although Secchi depth readings were very good, chlorophyll-a readings were
unexpectedly high, decreasing the Trophic State Index. Chlorophyll-a profiles at all
sample sites differed noticeably between June and July (Figure 4). In June all sample
sites, from the surface to 2.5 m, have similar chlorophyll-a levels and a very gradual
increase. At 3 m Brown/Waterlick site has a very dramatic increase in chlorophyll-a to
over 100 µg/L. In June, the dam profile is extremely low from surface to bottom. There
is almost no change in chlorophyll-a levels from 2.5 m to 3.5 m. Chlorophyll-a levels
increase noticeably at stream sample sites after 2.5 m. Chlorophyll-a levels for Timber
Lake in July produced a 53 TSI, classifying Timber Lake as eutrophic. Chlorophyll-a
levels in Timber Lake at all sites between the surface and 1.5 m more than double from
June 17 to July 26. Chlorophyll-a levels at all sites in July gradually increase or remain
the same until approximately 1.5 m. At 2 m Buffalo sample site reaches a high
chlorophyll-a of 21 µg/L. In June Buffalo sample site had a level of 4 µg/L at 2 m. In
July the overall temperature of Timber Lake increases, DO levels increase, and
chlorophyll-a production increases.
22
Timber Lake Chlorophyll-a Profile on June 17, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
Chlorophyll-a (micrograms/L)
0
20
40
60
Dam
80
Brow n/Waterlick
Buffalo
100
120
Timber Lake Chlorophyll-a Profile for July 26, 2005
Depth (m )
0
0.5
1
1.5
2
2.5
3
3.5
Chlorophyll-a (micrograms/L)
0
20
40
60
Dam
80
100
Brow n/Waterlick
Buffalo
120
Figure 4. – Chlorophyll-a profiles at Dam, Brown/Waterlick, and Buffalo sample sites to
a depth of 3.5 m taken June 17, 2005 and July 26, 2005.
23
Total phosphorus concentrations range from 0 µg/L to 103.4 µg/L (Table 2). Possible
data errors occurred at Buffalo and at Brown/Waterlick sample sites. The surface sample
at Buffalo on June 17 and both samples taken at Brown/Waterlick on July 26 resulted in
negligible amounts of total phosphorous (Table 2). On both sampling dates all sites, with
the exception of those just mentioned, have higher phosphorus concentrations at the
bottom depth sample than the surface sample. All sites bottom TP levels are higher than
surface levels. This stratification is also shown in Timber Lake’s temperature profiles
(Figure 4). Total phosphorus levels are expected to be lower, later in summer (Berman
1970). This expected trend is inconsistent with data collected from Timber Lake in June
and July. July total phosphorus levels are higher than June levels. Total phosphorus
concentrations at the dam surface site and at 5 m on June 17 are 7.88 µg/L and 55.64
µg/L, respectively. These TP levels are noticeably lower than concentrations collected at
the dam sample site on July 26. The July TP concentration at the dam site is 103.4 µg/L.
There was a rain event before July sampling. Higher TP levels suggest impacts of
riverine inputs after a storm event.
24
Table 2. – Total phosphorus levels at all Timber Lake sample sites collected on June 17,
2005 and July 26, 2005.
Date
6-17-05
Sample Site
Dam
Dam
Buffalo
Buffalo
Waterlick/Brown
Waterlick/Brown
Depth (m)
Surface
5
Surface
3
Surface
3
P (µg/L)
7.88
55.64
7.88
0
0.716
5.49
7-26-05
Dam
Dam
Buffalo
Buffalo
Waterlick/Brown
Waterlick/Brown
Surface
3
Surface
3
Surface
3
26.99
103.4
41.31
46.09
0
0
25
High numbers of zooplankton were found in Timber Lake. The total number of
zooplankton collected from both sample dates was 168 zooplankton per liter. Combining
data from both collection dates, out of all zooplankton there was a higher percentage of
Daphnia than all other species combined (Figure 5). Of the total zooplankton samples 98
zooplankton per liter identified as being Daphnia species. A very high percentage of the
pooled zooplankton is Daphnia, 58%. Of the total 168 zooplankton per liter, 42 percent
of the organisms were identified to be a species other than Daphnia. Other zooplankton
taxa identified were Mesocyclops, Bosmina, Diaptomus, Holopedium, Nauplii, and
Diaphanosoma.
26
Percent Daphnia in Timberlake
42% Other
58% Daphnia
Figure 5. – Percent Daphnia compared to all other zooplankton. The total zooplankton
taken is pooled data from one sampling on June 17, 2005 and one sampling on July 26,
2005 at the dam site on Timber Lake.
27
Stream Water Quality
The three main tributaries flowing into Timber Lake show variable water quality (Table
3). The headwaters of Waterlick Creek had lower quality indices than downstream
Waterlick (Table 3). Upper Waterlick values classify the steam as fair/good. This is very
typical of a stream in this area. Although the greatest number of fish was shocked at
Upper Waterlick Creek, the lowest amount of fish diversity was found there (Table 4).
The lower stretch of Waterlick produced water quality good/excellent. Downstream
Waterlick produced the highest PMA, 69.1, the highest quality EPT, 15, and the best FBI,
4.6. The lower stretch of Waterlick has very good biodiversity as well as very good
macroinvertebrate habitat.
Buffalo Creek water illustrates mixed water quality results. EPT numbers are excellent
while FBI numbers are fairly poor (Table 3). Buffalo Creek has the highest Species
Richness of all streams, 16, and the second highest PMA, 52.3. Buffalo Creek has the
highest fish diversity and the second highest total fish count, 63 (Table 4).
Brown Creek water quality is the most consistent throughout the stream, ranging from
fair to good. Brown Creek’s FBI and EPT indices describe good quality. Species
richness and PMA show fair water quality (Table 3). Overall stream water quality is
good.
28
Table 3.-Water quality comparison number generated for upstream and downstream
Waterlick Creek, Brown Creek, and Buffalo Creek from macroinvertebrate samples
collected on March 21, 2005.
Water Body FBI
EPT
Species
Richness
PMA
Upstream
Waterlick
Downstream
Waterlick
Buffalo
Creek
Brown
Creek
4.3
5
10
41.3
4.6
15
15
69.1
6
11
16
52.3
4.5
6
11
36.7
29
All streams have a high numbers of crayfish. The types of fish found in largest quantities
were the Fantail darter, Creek chub, Blue gill, Mountain Red belly dace, and Spotted bass
(Table 4). The highest diversity of fish types are found in Buffalo Creek, 11 types.
Upstream and downstream Waterlick Creek had the least diversity with 7 types of fish.
Ten different fish species were found in Brown Creek. The Fantail darter has the highest
population overall as well as being the prevalent fish species found in upstream Waterlick
Creek and Buffalo Creek (Table 4). The fish species with the single highest population in
one stream is the Creek chub found in downstream Waterlick.
30
Table 4. – Species and number of fish shocked and identified upstream and downstream
Waterlick, Buffalo, and Brown Creeks during 30 minute shocks. Waterlick Creek was
shocked on March 21, 2005. Buffalo Creek was shocked on May 6, 2005, and Brown
Creek was shocked on November 1, 2005.
Sample Site:
Fish Species
Perca flavescens
Luxilus
cerasinus
Etheostoma
flabellare
Etheostoma
olmstedi
Percina roanoka
Esox niger
Semotilus
atromaculatus
Catostomus
commersoni
Lepomis
macrochirus
Nocomis
leptocephalus
Micropterus
dolomieu
Phoxinus oreas
Clinostomus
funduloides
Micropterus
punctulatus
Noturus insignis
Thoburnia
rhothoeca
Total
Upstream
Waterlick
Common Name
Yellow Perch
Crescent Shiner
Downstream
Waterlick
Buffalo
Brown
1
0
0
0
1
1
7
0
14
9
20
6
2
5
1
0
0
0
0
0
1
7
0
1
0
32
7
4
0
0
6
0
0
10
10
20
3
3
4
1
0
0
1
0
0
21
1
0
0
9
5
1
0
0
0
16
0
0
0
2
0
27
0
85
0
62
1
59
Fantail Darter
Johnny Darter
Roanoke Darter
Chain Pickeral
Creek Chub
White Sucker
Blue Gill
Blue Headed
Chub
Smallmouth
Bass
Mountain
Redbelly Dace
Rosy-sided
Dace
Spotted Bass
Margined
Mad Tom
Torrent Sucker
31
Downstream Waterlick has the best fish indicator species (Table 5). The highest
percentage, 81.48%, of intolerant fish is found in downstream Waterlick. Intolerant
species are sensitive to chemical and physical stream disturbances. Intolerant species
will be the first to disappear with increased nutrients and sedimentation. Brown Creek
has the lowest percentage of intolerant fish species, 27.12%. Upstream Waterlick has the
highest percentage of Cyprinidae, 77.6%, and the second highest percentage of tolerant
species, 52.94%. Cyprinidae are more than tolerant than Percids. More impacted
streams will have a higher percentage of Cyprinidae than Percids. Upstream Waterlick
also has the highest percentage of omnivores, 42.35%. Omnivores are predominantly
tolerant fish species. Increases in omnivore populations will occur with decreases in
water quality. Brown Creek has the highest percentage of tolerant species, 72.88%. The
highest species diversity is found in Buffalo and Brown Creeks, both 10. Typically, two
to ten fish species can be found in small Virginia creeks. Brown Creek has the highest
number of water column insectivores, 33.90%, while Downstream Waterlick had the
lowest number, 0. Water column insectivores indicate impact from removal of riparian
buffer. Pool-benthic insectivores are a measure of sedimentation and chanelization.
Pool-benthic insectivores will decrease when sedimentation and stream chanelization
increase. Downstream Waterlick has the highest percent of intolerant species, percids,
and pool insectivores but has the lowest species diversity. The largest total number of
fish shocked was shocked at upstream Waterlick, 85.
32
Table 5. – Water quality indices comparing the results of one 30 minute fish shock on
each stream: downstream Waterlick, upstream Waterlick, Buffalo Creek, and Brown
Creek.
Downstream Upstream
Waterlick
Waterlick
Buffalo
Brown
7.00
7.00
10.00
10.00
Total Fish Species
Total # Fish Caught
% Percids
% Suckers
% Cyprinidae
% Catfishes
% Sunfish
% WC Insectivores
% Pool Insectivores
27.00
81.48
0.00
14.81
0.00
0.00
0.00
77.78
85.00
10.59
0.00
77.65
0.00
11.76
11.76
45.88
62.00
32.26
9.68
38.71
0.00
17.74
16.13
51.61
59.00
22.03
1.69
10.17
3.39
61.02
33.90
25.42
% Omnivores
% Carnivores
Total # WC
Insectivores
Total # Pool
Insectivores
% Tolerant
% Intolerant
14.84
7.41
0.00
42.35
0.00
10.00
29.03
3.23
10.00
11.86
28.81
20.00
22.00
39.00
32.00
15.00
18.52
81.48
52.94
47.06
46.77
53.23
72.88
27.12
33
Watershed Analysis
Timber Lake’s watershed consists predominantly of forested land and residential
development (Figure 6). Forested residential lands make up 27% of Timber Lake’s
watershed, 25% is open residential, and 24% is forested (Figure 6). Seventy-five percent
of Timber Lake’s watershed is forested and residential. A majority of urban land use is
located along route 460. Route 460 marks the horizontal southern border of Timber
Lake’s watershed and divides the watershed vertically to the east of Timber Lake. Most
of the open and forested residential land use is located to the northwest of route 460
(Figure 7). The portion of Timber Lake’s watershed southeast of route 460 is
predominantly open residential and forested land use. There is more forested land use
southeast of US route 460 than northwest of route 460. The northwest section of the
watershed is more forested residential and open residential than the southeast portion
(Figure 7).
34
Timberlake Watershed
Landuses
Bare Ground
Forested
2%
13%
4%
Forested
Residential
24%
Grass
25%
Open Residential
Urban
5%
27%
Water
Figure 6. – Timber Lake watershed percentages of land use.
35
4%
24%
27%
25%
25%
5%
13%
2%
Figure 7. – Timber Lake watershed land use map.
36
Discussion
Stream Water Quality
Waterlick, Buffalo, and Brown Creeks are somewhat impacted but have good water
quality. EPT, FBI, PMA, and SR indices illustrate three urban streams that are not
pristine but have much better quality than other streams found throughout Lynchburg,
Virginia. Waterlick Creek has very good FBI and PMA and an excellent EPT (Table 3).
Buffalo Creek has great Species Richness (Table 3). The impact on the streams is shown
occasionally. Buffalo Creek has an FBI of 6, being fairly poor and a SR of 16 being fair.
Brown Creek also has a fair Species Richness (Table 3).
Analyses of the fish shocked from each of the three streams illustrate stream water
quality similar to that found from macroinvertebrate analysis. Downstream Waterlick is
shown to be least impacted while Brown confirms effects of watershed development.
Macroinvertebrates indicate downstream Waterlick as having the best water quality based
on the EPT index and the best PMA. These results are consistent with the fish species
collected. Macroinvertebrate and fish data indicate Brown as the most impacted stream
and downstream Waterlick as least impacted.
Timber Lake’s tributaries have much better water quality than more urban streams
because the watershed is less developed (Table 6). There is less impervious surface area
in Timber Lake’s watershed so there is less direct storm water run-off, and run-off that
37
does occur has lower flow rates. Run-off entering Waterlick, Buffalo, and Brown Creeks
has more riparian buffers through which filtration occurs.
38
Table 6. – Compares water quality of Waterlick Creek to two other local Lynchburg
creeks.
Water Body FBI
EPT
Species
Richness
PMA
EPT %
Waterlick
Creek
3.79
14
18
56.4
78%
Rock Castle
Creek at
Cracker
Barrel on
Wards Road
Dreaming
Creek near
Charley’s
Restaurant
6.1
5
9
37.9
56%
7.5
1
8
34.1
12%
39
Water quality of tributaries directly relate to the water quality of the lakes they run in to
(Dodson 2005, Bennett et al. 2001, Mankin et al. 2003, Moore et al. 2001). Timber Lake
is currently influenced by riverine inputs, but still controlled by in-lake functions. This is
evident when temperature and total phosphorus profiles are examined (Figure 3 and
Table 2). Lake temperatures found at the dam sample site are relative to those found at
the stream sample sites. Impact on Timber Lake from the streams can be seen by
comparing total phosphorus concentrations from June and July. Following normal lake
functions, TP concentrations will become more limiting later in summer (Berman 1970).
This means that TP levels taken in July are expected to be lower than levels collected in
June. Table 3 shows that in Timber Lake, July TP concentrations are actually higher than
in June. The most likely cause of higher July concentrations is the rain event that
occurred the night before sampling in July. Higher TP concentrations will result in
spikes of chlorophyll-a (Dillon and Rigler 1974, Sakamoto 1966). Increased chlorophylla concentrations will decrease visibility and overwhelm Daphnia (McCauley et al. 1988,
Sarnell 1992).
Previous studies have shown that increased shoreline and watershed development will
decrease coarse woody debris and riparian buffers (Christensen et al. 1996, Eilers et al.
2001, Jennings et al. 2003, Moore et al. 2001). The result of fewer buffers along streams
results in increased runoff and storm water flow into streams. Without buffers storm
water runoff is not given a chance to be filtered. Raised levels of sediment and nutrient
flow into Waterlick, Buffalo, and Brown Creeks influence phosphorus levels in Timber
40
Lake. When construction of Braxton Park begins, the flow of sediment and nutrients into
Waterlick will dramatically increase.
A local example of a lake influenced by dramatic increases in watershed development is
College Lake. The City of Lynchburg has developed rapidly and extensively over the
past 70 years. Development that has taken place has failed to use successful Virginia’s
Best Management Practices and as a result, has severely degraded the water quality of
College Lake and other local streams. Streams within College Lake’s watershed bring
fast flowing storm water runoff with high levels of sediment and nutrients. Over the
course of more than 70 years, College Lake has become a eutrophic lake controlled by
completely riverine inputs. Dissolved oxygen levels by the College Lake dam are often
anoxic. Total Suspended Solids and Total Dissolved Solids are extremely high. College
Lake sediment depths are continually increasing. In addition, there are usually very low
levels of chlorophyll-a and relatively high total phosphorus concentrations. There are
occasions, however, when sunlight penetrates deeper than usual and toxic algal blooms
occur (Paerl 1988).
Brown, Waterlick, and Buffalo Creeks are in overall good condition (Table 6). Each is
somewhat impacted but good quality for urban streams. Development of Braxton Park
will diminish the streams’ water quality. The construction company has agreed to build
storm water ponds and abide by Virginia state standard Best Management Practices.
These precautions will prevent some sediment from the construction site running off into
41
the headwaters of Waterlick Creek but not enough to maintain Waterlick’s current water
quality.
Lake Water Quality
The trophic state of Timber Lake is currently around a mesotrophic level. The Secchi
TSI is 41.9, the chlorophyll-a TSI is 53, and the TP TSI is 51.9. Based on the Carlson
Trophic State Index, Timber Lake received a TSI value 40-50. The Carlson Index refers
to a lake in this range as “water moderately clear, but increasing probability of anoxia in
hypolimnion during summer” (Carlson 1977). There is a sufficient amount of
phosphorus inputs to stimulate algal growth, but it does not overwhelm the zooplankton.
The higher Secchi depths per unit phosphorus indicate the consumption of the smaller
celled chlorophyll-a producing organisms.
Lakes with similar trophic states in North Carolina showed characteristics that could be
correlated to those found in Timberlake. The Burlington Reservoir, in Alamance County,
was characterized as a mesotrophic lake (NC Assessment 1992). The drainage area of
the Burlington Reservoir consists primarily of forested acreage and lands used for
agriculture (NC Assessment 1992). Total phosphorus and chlorophyll-a levels were
similar to numbers found in Timberlake. It was found in Burlington Reservoir that the
zooplankton relationship with chlorophyll-a was also similar to Timberlake in that 40%
of the total biovolume made up only 2% of the total density (NC Assessment 1992).
Burlington Reservoir was found to have moderate nutrient concentrations, meaning a
42
healthy lake that is somewhat impacted, as was found with Timber Lake (NC Assessment
1992).
Timber Lake currently has a good lake state but shows signs of impact from
development. The water quality has the potential to change drastically with the
construction of buildings and the deforestation of the land surrounding the lake’s
watershed. At a given point the lake will rapidly shift trophic states from mesotrophic to
eutrophic. This will occur when nutrient and sediment inputs increase dramatically above
current levels. This is supported by the high percentage of Daphnia found in Timber
Lake and the related low chlorophyll-a levels (Figure 4). The total phosphorus levels are
high enough to represent a eutrophic lake. The high levels of Daphnia grazing on
phytoplankton are preventing high levels of chlorophyll-a and algal blooms from
occurring. Once the lake is nutrient-enriched, Daphnia will decline, and primary
production will dramatically increase shifting Timberlake to a eutrophic state.
The exact point at which Timber Lake will transform from a mesotrophic lake to a
eutrophic lake is not known. Current levels of total phosphorus are high enough that
Timber Lake should be illustrating signs of more production than are being shown.
Timber Lake’s water is predominantly clear. Primary production has not completely
taken over the lake due to the high percentage of Daphnia found in the lake. Figure 4
shows that from two zooplankton samples collected in the lake, the percentage of
Daphnia is higher than the total number of other zooplankton species. At least six other
species were identified in the lake. The higher percentage of Daphnia reduces
43
chlorophyll-a in the presence of high levels of total phosphorus (Sarnelle 1992). Higher
levels of total phosphorus increases primary production and total amount of chlorophyll-a
present, which relatively increases Daphnia levels (McCauley et al. 1988 Sarnelle 1992).
Daphnia graze on algae, reducing the amount of chlorophyll-a present (Sarnelle 1992).
As nutrients in the lake increase well above the current nutrient levels, Daphnia have
been shown to decline (McCauley et. al. 1988, Sarnelle 1992). The death of Daphnia
consequently leads to algal blooms (McCauley et al. 1988, Sarnelle 1992). The level of
added nutrient input at which the lake will show these eutrophic symptoms is unknown.
At some point when the nutrient inputs are slightly raised, the lake has the potential to
rapidly shift to showing eutrophic symptoms. Timber Lake is poised to show
eutrophication effects. A small disturbance could tip the current nutrient balance.
Timber Lake could potentially show signs of increased primary production due to
decreased levels of Daphnia, within a few days or weeks (McCauley et al. 1988).
The flow of energy in lakes is naturally controlled internally by biological factors.
Although Timber Lake is currently being impacted by external factors, such as watershed
development, overall the lake is still controlled internally. This means that biological
factors, Daphnia, are controlling the energy flow throughout Timber Lake and balancing
nutrients flowing into the lake. High levels of Daphnia illustrate an impacted lake that
could easily change from a lake controlled biologically and internally to a lake controlled
externally. The water quality in Timber Lake is being externally impacted by Waterlick,
Buffalo, and Brown Creek. The nutrient and sediment input into these streams directly
effects Timber Lake. If the nutrient and sediment input into the streams become too high,
44
Timber Lake will be controlled chemically. College Lake is an example of a lake
controlled by non-biological factors. Data collected from the three streams illustrate
impacted streams that still have fair water quality, as shown in Table 3. The water quality
within Timber Lake is controlled internally by Daphnia feeding on algae.
Increases in urbanization within Timber Lake’s watershed will speed up the
eutrophication of Timber Lake. Currently, the watershed is composed primarily of
forested and forested residential land uses. This is shown in the GIS map of the area
surrounding Timber Lake. Because the watershed is primarily forested or forested
residential, increased urbanization will have dramatic effects on Timber Lake’s
watershed. Sediment and nutrient flows can be expected to increase causing streams to
be more embedded with decreases in species richness. Owing to increases in nutrient
flow, effects also may be enough to change the controlling factors of the lake to external
factors. The lake is currently controlled by riverine input. This can be shown by the
difference between the temperature and dissolved oxygen profiles. There is slight
temperature stratification within Timber Lake, however there are definite changes in
levels of DO. The second increase in DO (Figure 1) is due to increases in primary
production. If the lake was controlled principally by its own currents, there would be a
more defined thermal stratification.
The absence of anoxic water represents very good quality lake. Expected temperature
profiles for a regional lake during June or July would show a defined stratification
(Dodson 2005). Timber Lake’s temperature profiles, however, showed only a slight
45
stratification. The thermocline was at approximately 1.3 m (Figure 2). There is not a
noticeable relationship between dissolved oxygen and temperature profiles. When lakes
are controlled by stream inputs, rather than in-lake currents, the temperature profiles and
dissolved oxygen profiles will not have a significant relationship.
Possible errors in this study are human errors in calculation and analysis. Watershed land
use characterization was somewhat subjective and not exact. There is additional error in
GPS points so that there is also error in the watershed delineation Difference in
sampling dates, such as recent weather conditions, may have influenced results. There
was a slight difference in techniques depending on sampling date and specific stream.
Error may be in macroinvertebrate, fish, and zooplankton identification.
Conclusion
Timber Lake and its tributaries’ water quality greatly exceed similar, local lakes and
streams. Waterlick, Brown, and Buffalo Creek are three of the last few streams in the
Lynchburg area with good water quality. The quality of these three streams should be
preserved by controlling development in their watersheds. Low-impact development and
the use of Best Management Practices will best help to maintain and preserve their water
quality. If these streams are not protected from increases in impervious surfaces their
water quality will change drastically. Decreases in stream water quality will directly
affect the water quality of Timber Lake. Timber Lake has a history of sedimentation
problems. Currently, Timber Lake appears clear and in a good trophic state. This good
46
state has the potential to change quickly with increases in sediment and nutrient flow
from the lake’s tributaries. If the lake changes dramatically there are many negative
repercussions. The economic value of lake properties may decrease. If the lake is
damaged enough, the cost of revamping the lake may be too high. The lake will no
longer be clear but overwhelmed with productivity. Overproduction will include algal
blooms, with consequent decreases in fish populations, reducing property values while
incurring high clean up expenses.
If construction begins at the headwaters of Waterlick there is a much greater chance that
Timber Lake will become eutrophic sooner. Total phosphorus levels in Timber Lake are
already high, the addition of increased nutrient and sediment inputs into the lake will
initially increase production but lead to the decline of Timber Lake. Timber Lake is on
its way to resembling College Lake if measures are not taken to maintain water quality
and reduce future negative impacts of watershed and shoreline development.
Timber Lake is an opportunity to implement low-impact development as a method for
maintaining and preserving water quality by limiting impacts of impervious surfaces.
Low-impacts development targets negative effects of increased impervious surfaces such
as increased flow of storm water run off. Examples of low-impact development are
pervious parking lots, conserving natural resources, routing stormwater to control runoff
flow, and general pollution prevention practices (Liaw et al. 2000).
47
Timberlake residents have brought many points against the Braxton Park construction
project. The school systems are overcrowded and additional housing will amplify this
problem by spreading educational resources thinner (Campbell County Board of
Supervisor’s Meeting 2005). Concerns about additional housing include difficulty with
fire and police efforts. More housing in Campbell County means more people that fire
and police have to look after (Campbell County Board of Supervisor’s Meeting 2005). In
regards to citizen concerns the developer has agreed to a proffer of providing $20,000 to
the Timber Lake Watershed Improvement District. This money is intended to address
existing problems with tributaries surrounding Timber Lake or to go towards a study of
the area. The developer has also agreed to follow City of Lynchburg requirements for
Best Management Practices and to provide stabilized check dams in the outlet creek
below Timber Lake subject to DEQ requirements and approvals (Campbell County Board
of Supervisor’s Meeting 2005).
Establishing low-impact development will help to improve Campbell County
environmentally and economically. Before the Timber Lake dam broke, shoreline
development degraded the quality of the lake. Extreme levels of sedimentation and
overproduction occurred. After the dam broke the lake was dredged and restored. Since
restoration, the lake has been impacted and is now at a mesotrophic trophic state. Since
Timber Lake has been designated a Watershed Improvement District, the homeowner’s
association has the power to tax residents. The tax money raised can be used for
improvements to the lake and its watershed as well as for preserving and maintaining the
lake’s water quality. The homeowner’s association has yet to establish a tax. If Timber
Lake reaches a eutrophic state, it may require more resources than are available to restore
48
the lake’s condition again. For this reason Timber Lake and its watershed’s water quality
needs to be preserved and maintained effectively. This can be accomplished by
regulating watershed development and establishing a low-impact development precedent
within Timber Lake’s watershed. If development around Timber Lake sets a precedent of
low-impact development and water quality awareness, surrounding communities such as
Smith Mountain Lake and similar areas may take initiative to follow Timber Lake’s
example.
49
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52
Appendices
Appendix A. – Family Biotic Index
Family Biotic Index
0.00-3.75
3.76-4.25
Water Quality
Excellent
Very Good
4.26-5.00
Good
5.01-5.75
5.76-6.5
Fair
Fairly Poor
76.51-7.25
Poor
7.26-10
Very Poor
Degree of Organic Pollution
Organic Pollution Unlikely
Possible Slight Organic
Pollution
Some Organic Pollution
Probable
Substantial Pollution Likely
Very Substantial Pollution
Likely
Very Substantial Pollution
Likely
Severe Organic Pollution
Appendix B. – Species Richness index.
Species Richness
>26
19-26
11-18
0-10
Water Quality
Excellent-Non Impacted
Good-Slight Impact
Fair-Moderate Impacts
Poor-Severe Impacts
Appendix C. – EPT index
EPT
>10
6-9
2-5
0-1
Water Quality
Excellent – Non Impacted
Good – Slight Impact
Fair – Moderate Impacts
Poor – Severe Impact
Appendix D. – Percent Model Affinity index
Percent Model Affinity
>64
50-64
35-49
<35
Water Quality
Excellent – Non Impacted
Good – Slight Impact
Fair – Moderate Impacts
Poor – Severe Impacts
53
Acknowledgments
Many people were involved in helping me get through this project alive and somewhat
sane. Dr. Gannicott and Steve Burris, I can not thank you both enough for being amazing
chemistry teachers for an extremely non-chemistry oriented environmental science
student. Desi Justis, you have always been magnificently helpful for everything. Dr.
Cowden, thank you so much for always being down-to-earth and really help keep things
in perspective. Thank you, Dr. Perault for helping with the GIS portion of my thesis and
for giving any extra grief that Dr. Shahady may have lacked on any given day. I could
not have completed this thesis if it was not for the help of David Ford and Dr. Shahady.
These two contributed immensely to this study by collecting important data while I was
off exploring other parts of the world. Each was sure to give the appropriate amount of
joshing for it when I returned. Dr. Shahady and Dave, after this past summer you guys
thickened my skin ‘just a little bit,’ but enough ‘to get my arms around it.’ I have learned
so much from both of you over the course of this project that will last far beyond the
completion of this thesis. Most noticeably are the random facts I have picked up in
addition to learning how to effectively and invisibly shift blame. Dr. Shahady, thank you
for graduating me from ‘stupid.’
54