Sweet Sea Observations: How Great Lakes Observations can Work for You June 21, 2011

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Sweet Sea Observations: How Great Lakes Observations can Work for You

June 21, 2011

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Overview

• Ontario Clean Water Act – Source Water Protection Program

• Lake Erie Source Protection Region – Characteristics

• Timelines for Plan Development• Vulnerable Areas – Surface Water• Approach to Establishing Protection Zones• Hydrodynamic Model and Data Needs• Conclusions

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The Ontario Clean Water Act• Passed in 2006 to implement recommendations

on source protection in the Walkerton Report• Protect current and

future drinking watersources fromcontaminationand depletion

• One of five layers in a‘multi-barrier’ approach

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• Lake Erie SourceProtection Region−Kettle Creek−Grand River−Long Point Region−Catfish Creek

• One plan will be developed for each watershed

• Process led by multi-stakeholder Source Protection Committee

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Steps in the process

• Characterization Reports: Complete• Terms of Reference: Complete• Technical studies: Complete• Assessment Reports: Nearing completion• Source Protection Plans: complete by 2012

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Lake Erie Region – Some Stats

CA Populat’nPopulation on Municipal Water

Number of Systems Municipal Water Taking (m3/year)

% water taking of total in WatershedGW GW/SW SW

Kettle 49’000 56’000* 1 0 1 6’000’000* 76%Catfish 20’000 500 1 0 0 1’300’000 22%

Long Point 113’000 61’000** 6 1 3 10’400’000** 18%

Grand 900’000 753’000 45 2 3 81’600’000 53%

TOTAL 1’082’000 870’500 53 3 7 99’300’000 n/a

* includes water going to residents in the City of London

**includes water going to residents in Hagersville, Jarvis, outside of watershed

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Vulnerable Areas and Threats

Vulnerable areas include:−Wellhead Protection

Areas (WHPA)− Intake Protection Zones

(IPZ)

Threats−Kettle Creek – 2−Catfish Creek – 32−Long Point Region – 343−Grand River – 6912

TOTAL Threats = 7289

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Intake Protection Zones• How quickly

can pollutantsget to the intake?

• Three zones:− IPZ 1: 1 km around intake− IPZ 2: 2-hour Time of

Travel− IPZ 3: upstream areas

• Vulnerability ratedon 10-point scale

• Alternate method:‘events-based’ reviewof local conditions

IPZ – 3

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Port Stanley IPZ

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Hydrodynamic Model

Bathymetryo Various surveys (CHS,

NOAA)

Water Levelso Port Stanley (CHS)

Waveso Mostly offshore buoys

(MEDS, NOAA, MNR)

Temperatureo Buoy (MEDS)

Currentso Consultant survey

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Hydrodynamic Model UseHydrodynamic model was used to:

Delineate the in-water area of an IPZ-2

Conduct event based modeling for the designation of an IPZ-3

IPZ-2

Used critical combinations of wind and wave stress (10 year) to delineate the area of the 2 hour time of travel to the intake

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Hydrodynamic Model – IPZ-3

IPZ-3 Event Based Approach

2 possible spill scenarios were investigated under extreme event conditions:

5000m3 of Urea Ammonium Nitrate at the mouth of Kettle Creek (50m3/s flow rate in Kettle Creek and 10 m/s wind speed)

6000L of Diesel Fuel to a drain discharging near the intake (5 m/s offshore wind)

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Hydrodynamic Model – IPZ-3

Example of Results: Urea Ammonium Nitrate Spill Scenario

Concentration of Nitrate at the intake would exceed benchmark levels and should be included as a significant

drinking water threat

1 hour spill (27 hours after spill) 27 hour spill (27 hours after spill)

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Uncertainty and Gaps Limitations to the models based on time and

resources constraints

Wave and wind measurements were from areas offshore from the intake locations

Water currents information was very limited and additional information was gathered to complete the model

Event modeling for IPZ3 included many assumptions on extreme conditions

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Conclusion Science-based approach to protecting drinking water

sources

Used available as well as new observations to establish protection zones and identify drinking water threats

Established process to deal with uncertainty and data gaps

peer review process

mandatory documentation in Assessment Report as per technical rules

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