Forecasting Beach Closings and Conditions in the Great Lakes

Forecasting Beach Closures Using
Statistical Methods
Cynthia Sellinger
NOAA/GLERL
Stephen Brandt
Oregon State
University
Timothy Hunter
NOAA/GLERL

Objectives
• Develop a statistical Beach Closure Forecast Model
that includes watershed factors and is transportable
to any beach influenced by watersheds
• Identify the watershed driving forces behind beach
closures

Hypothesis:
Watershed hydrology plays a major role in beach
closures
Goals:
• Identify the statistical linkages between spatially-explicit
physical environmental data and bacterial data.
• Develop a statistical model that could apply to any beach
using easily-available, public data.
• Develop the model in an exportable and usable language
(IDL)
Initial focus:
Great Lakes with the Grand River watershed (Lake Michigan)
as the first test case.

Water Quality Standards for Waters --
Bacteria in the Environment
• BEACH Act (Amending the Clean Water Act--October
10,2000) requires studies associated with pathogens
and human health.
• Escherichia coli (E.coli) bacteria lives in the digestive
system of humans and other warm-blooded animals.
• Epidemiological studies of fresh water bathing
beaches have established a direct relationship
between the density of E. coli in the water and the
occurrence of swimming-related gastroenteritis,
respiratory, ear, and skin symptoms.
State of Michigan Department of Environmental Quality; EPA—
Critical Path Science Plan (08/31/07)

Major Sources of Contamination
• Aging Sewer Systems
-> Combined Sewer Overflows (CSOs)
-> Sanitary Sewer Overflows (SSOs)
-> Leaking Septic Systems (LSSs)
Trash hangs on trees and creek polluted with
sewage
• Confined Animal
Feeding Operations
(CAFOs)
Approximately 2 -million
hogs reside in Southwestern
Ontario. Each pig produces
about 4-times the amount of
waste as humans

Sampling for E. coli
• County Health Departments
routinely collect beach water
quality samples.
• Health departments must take
a minimum of three samples.
• The daily geometric mean
must be below 300 E. coli
counts per 100 milliliters of
water to be considered safe
for swimming.
State of Michigan Department of Environmental Quality

Grand River Watershed
Grand
Rapids
Lansing
•14,215 Square Kilometers
• Includes Large Urban Areas
(Lansing)
• Highly Agricultural
Percent Cropland
USAC—Detroit District

Study Site
Grand Haven State Park
•Public Owned
•Public Access Beach
•Monitored by the
Ottawa County Health
Department
The Grand
River

Forecast Model
Inputs:
•Air Temperature
• Precipitation
• Wind Directions
• Storm Runoff
Spatially-Explicit,
Watershed- Specific Hydrometeorological/Biological
Model
Output:
• E.coli Counts

E. Coli Counts (#/100 milliliters of water)

National Weather Service’s Precipitation and
Temperature Stations
Approximately 48
stations with up to
42,000 days of
data per station

National Weather Service
Precipitation and Temperature Data
1880
1880

Grand River Stream flow in Cubic Meters per
Second (United States Geological Survey)

Ground water Levels (m) (Kent County) –
Well not affected by pumping

Grand River’s Stream flow and Groundwater flow
Hydrographs
•It takes approximately
six days for rain to reach
the coast from the entire
basin.
•Groundwater flow is
approximately 63% of
total flow

National Data Buoy Center
Wind Directional Data

Daily Sewage Discharges into the Grand River in
Millions of Gallons per Day (Michigan DEQ)

E. Coli Frequency Distribution Histogram
• Non-normal Distribution – Transformed to the Natural Log

Time Series Analysis Between Grand Haven Ecoli
and Precipitation—Lag Relationships
0 2
4 6
Time Lag in Days

Four-Dimensional Data Visualization Tool
E. Coli Data
Precipitation
Amounts
Wind Directions
Air
Temperatures

Spatially-Explicit, Watershed-Specific
Hydro-meteorological/Biological Model
E.
C
B T
7
13
19
i
B
B W
i
i
B R
0
8
B P
14
20
1
B T
i 1
i
B W
B R
i 1
i 1
B P
9
2
B T
21
i 2
15
i 1
B W
B R
i 2
i 2
B P
3
10
i 2
B T
i 3
B W
i 3
i 4
Where:
E.C = Ecoli Count (#/100ml)
P = Precipitation Totals (mm)
T = Temperature (F)
W = Wind Direction (Degrees)
R = Runoff (cms)
Kruskal-Wallis α = .05
p = 0.712613
22
16
B R
B P
4
11
i 3
i 3
B T
i 4
23
17
B R
B P
5
12
B W
i 4
i 4
B T
i 5
24
18
B R
B P
6
B W
i 5
i 5
i 5

Modeled
Measured versus Modeled E.coli Counts
R 2 = .76
Measured

July 18 th 2005 Episodic Event

July 18 2005—Episodic Event
E. Coli Data
Precipitation
Amounts
Wind Directions
Air
Temperatures

45
18
Hurricane Dennis
4 - 13 July 2005
40
35
13
16
12
14
15
17
Hurricane
Tropical Storm
Tropical Dep.
Extratropical
Subtr. Storm
Subtr. Dep.
Low / Wave
00 UTC Pos/Date
11
12 UTC Position
30
PPP Min. press (mb)
25
930 mb
10
9
20
8
7
15
6
5
-100 -95 -90 -85 -80 -75 -70 -65 -60 -55

Hurricane Dennis
• Made Landfall in Florida July 10 th
• Responsible for 42 deaths
• Estimated $2.23 billion in damages
• The FDVT showed major cyclonic rotation accompanied
by watershed-wide rain.
• Brought large amounts of rain in the Great Lakes Region
• Half the monthly total of rain fell on the city of Lansing on
July 16 th
• 91 million of gallons of untreated sewage released into
the Grand River (July 18 th – 27th).

July 27 th 2007 Episodic Event

July 27 th 2007 Anti-Cyclonic Event
E. Coli Data
Precipitation
Amounts
Wind Directions
Air
Temperatures

July 27 th 2007 Episodic – High Pressure System
• Event measured on July 27 th 2007 at 464 counts per day
• Model predicted 360 counts per day for July 23 rd
• FDVT showed minor precipitation except for the 26 th
• FDVT showed average watershed temperatures increased
by 6 degrees in 10 days
• FDVT showed major anti-cyclonic circulation—fair weather
•The Model responded to the increase air temperatures and
the anti-cyclonic wind rotation.
•Several studies indicate that fecal bacteria may persist
and/or re-grow in sand
•133 million gallons of untreated sewage was released into
the Grand River from the city of Lansing for May – July.

July 27 th 2007 Episodic Event

May 31, 2007 Event
• Temperatures increased 14 0 F
in five days
• Major Basin Precipitation on
the 26 th and 27 th .
• Sewage outflows totaled 130
million gallons per day for March
- April

Next Steps
Other Applications:
• Other Grand River Beaches (North Beach)
• Saginaw Bay Beaches
• West Coast Beaches (Partners?)
Future Plans:
Inputs:
•Air Temperature
• Precipitation
• Wind Directions
• Storm Runoff
Spatially-Explicit,
Watershed- Specific Hydrometeorological/Biological
Model
Output:
• E.coli Counts
Hydrodynamic-
Deterministic
Model

Questions?