About the SMLA Water Quality Monitoring ProgramMonitoring the Waters of Smith Mountain Lake Since 1987
Photos of the Cedar Cabin at LakeAway Vacation Rentals on
Smith Mountain Lake
Starting this summer SMLA will begin our 30th year of monitoring
the quality of the water within the main lake in SML and also
where the rivers and streams enter the lake. This is important to
insure the water remains safe for everyone to use and enjoy. We
have approximately 60 SMLA member volunteers monitoring 85 sites
around the lake during the summer. It is easy, fun and rewarding
to know that as a monitor you are good stewards of this beautiful
lake as well as helping to insure that water quality remains
Actually the quality of the water in SML is remarkable for a fifty
year old lake and showing little signs of change over the last 10
years. SMLA is proud of that fact and our water quality monitoring
program. SMLA’s partners during the last 30 years of water quality
monitoring are the many volunteers and Ferrum College. There many
SMLA volunteers who have given freely their time and use of the
their boat and gas to go out and check the clarity of the lake
water and collect samples of the water at their prescribed sites
around the lake six times during the summer. Ferrum College
Professors, staff and student interns conduct additional
monitoring and perform all of the analysis of the water and
biological samples in their exceptional environmental sciences
laboratory on their beautiful campus located in Ferrum Virginia.
The resulting data is reported to the Virginia Department of
Environmental Quality, Virginia Department of Health, the
volunteers, SMLA members and the public. If there is an issue with
the quality of the water SMLA promptly alerts our members, the
public and respective agencies.
To be a Water Quality Monitor contact Larry Iceman at email@example.com or call
the SMLA office at (540) 719-0690. Please leave your name, phone
#, and or E-mail address and state your interest and or question
if no one is available to answer the phone. Ferrum College
provides the monitoring equipment and training for the volunteers.
No prior experience is required to be a monitor. It is a good
family fun boating activity. Their will be a kickoff meeting in
May. Please call or e-mail for details. You will need a boat, ice
chest for water and the samples, sunscreen and sunglasses.
While boating and monitoring the water please wear your life
jackets. It is your life you are protecting as well as any others
on your boat. Your Safety comes first.
Volunteer MonitorsTraining and Duties
Water Quality Monitoring Volunteers on Smith Mountain Lake
Each monitoring season begins in mid-May with a training and
organizational meeting hosted by SMLA and Ferrum College.
Over 80 volunteers monitor 50 sites by measuring water clarity
using a secchi disc and collecting water samples from a boat every
other week (6 - 1 hour events) until mid-August. Student interns
from Ferrum College travel around the lake every other week to
pick up the samples for analysis at the Ferrum College Water
Water Quality Monitoring ReportsRead the Results; Follow the Trends
SMLA Water Quality Monitoring Reports
1. EXECUTIVE SUMMARY from the 2015 Final
The Smith Mountain Lake Volunteer Water
Quality Monitoring Program was initiated in 1987 and has
functioned each year since. The Smith Mountain Lake Association
and scientists from Ferrum College cooperatively administer the
program. The mission of the program is to monitor water quality in
Smith Mountain Lake and to encourage active participation of the
lake community in protecting this resource.
2015 monitoring season began in mid-May with a training and
organizational meeting. The volunteer monitors measured water
clarity and collected water samples every other week until
mid-August. Student interns from Ferrum College traveled around
the lake every other week to pick up the samples for analysis at
the Ferrum College Water Quality Lab. During this trip, the
interns also collected grab samples from 21 tributaries that were
analyzed for total phosphorus. Also on a bi-weekly schedule,
Ferrum College personnel collected additional lake samples for
bacterial analysis. Twice during the season, samples were
collected from tributaries (22 in May and 22 in August) for
bacterial source tracking.
trophic status (an indication of the degree of aging a lake has
sustained) of Smith Mountain Lake is monitored by measuring three
parameters: total phosphorus as an indicator of nutrient
enrichment, chlorophyll-a as an indicator of algal
biomass, and Secchi depth as an indicator of water clarity.
According to the Virginia Department of Environmental Quality,
enumerating the bacterial species chosen as indicator organisms
assesses bacterial water quality. In 2015, E. coli was
again enumerated to assess the bacterial populations in Smith
profile monitoring has continued to provide interesting insights
about the dynamics of Smith Mountain Lake. At five locations in
the main channels of the lake, measurements of dissolved oxygen,
temperature, pH and conductivity are taken as a function of depth.
These profiles are measured six times during the summer.
2015, plankton tow samples were taken during the summer for two
types of sample sites. Horizontal plankton tow samples were
collected and analyzed six times at bacterial sampling sites, and
vertical plankton tow samples were collected and analyzed five
times at depth profile monitoring sites. Algae were identified and
grouped by algal divisions.
Conclusions – Trophic Status
In 2015, water quality improved from the
upper channels to the dam, as indicated by decreasing total
phosphorus, total nitrogen, and chlorophyll-a concentrations
and increasing Secchi depth with decreasing distance to the dam.
The average total phosphorus concentration in the lake decreased
slightly in 2015, down 15.6 percent from last year, as did the
average total nitrogen concentration, down 21.6 percent from last
year. Average chlorophyll-a concentration increased this
year by 151.9 percent. However, it is important to note that
chlorophyll-a values were significantly lower than normal
last year. The average chlorophyll-a concentration last
year was 2.7 ppb. This year's average chlorophyll concentration of
6.8 ppb is not significantly higher than the 10 year average
concentration of 5.8 ppb. The average Secchi depth has held fairly
steady for the past several years and was the same value as last
year, 2.3 m.
In 2015 the average combined TSI was
below 50 (46.9), indicating that, on average, the lake is in the
early stages of eutrophic conditions. However, the TSI did
increase slightly from the 2014 value of 45.1. Similar to 2014,
all three trophic status indicators are consistent with beginning
stages of eutrophication. The eutrophic area of the lake has now
moved 1 mile closer to the dam (18 miles in 2014 to 17 miles in
Conclusions – Algae in Smith
Green algae were the dominant
algal population group found in Smith Mountain Lake in 2015.
Blue-green algae levels remained low in 2015 and there were
no reports of algal blooms by lake residents. Although green
algae counts were higher in some sample dates this is still
mostly due to the large number of single celled Chlorella
species. The highest levels of algae in the lake are
found at the headwater sites and some marina sites. Rainfall
timing and levels may be one of the highest influences on
algal growth and is likely tied to higher nitrogen levels.
Preliminary observations of rainfall data seem to correspond
with spikes in algal growth and should be monitored in 2016.
Newly released global studies on lakes indicate a
temperature rise in lakes worldwide (O’Reilly et al, 2015).
This should be monitored at Smith Mountain Lake to determine
its impact on lake water quality. When water temperatures
warm over time, it will be important to continue to sample
regular sites and sites reported by residents in shallow
coves around the lake where algal blooms are reported.
Conclusions – Dissolved Oxygen,
Temperature, pH and Conductivity Lake Depth Profiles
Sufficient depth profile data have
now been collected to enable meaningful comparison between
rates of change and absolute parameter values over the
course of the summer. The temperature profiles indicate that
the thermocline at most sample sites is moving lower in the
water column. The bottom of the lake becomes anaerobic (zero
parts per million dissolved oxygen) in June rather than
July. This is problematic as it impacts aquatic life by
forcing them to move closer to the surface earlier in the
summer, thus increasing thermal stress on the animals.
Continued study of thermal stratification, using depth
profiling, and algal dynamics will provide the scientific
data necessary to effectively manage Smith Mountain Lake as
Conclusions – Escherichia coli
Measurements and Bacterial Source Tracking
The bacteria populations, specifically E.
coli, in Smith Mountain Lake in 2015 were slightly higher
than they were in 2014. Since we started measuring E. coli in
2006, the 2013 counts were the highest and the 2014 counts were
the lowest. The 2015 data are more typical of bacterial
populations found in the lake. The comparison of marinas and
non-marinas showed differences in E. coli values in 2015
as usual, and showed a higher mean in marina sites than in
non-marina sites (118 percent higher at marina sites).