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Large-Scale Riverine Bathymetric

LiDAR Collection and Application

to Floodplain Mapping

Floodplain Mapping Technology Transfer Workshop

March 5, 2019

Scott Robertson, P.Eng.

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Presentation Overview

1. Introduction to the Project

2. Considerations

3. Trials and Tribulations

4. Initial Results

5. Next Steps

6. Recommendations

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Introduction to the Project

➢ Undertaking large-scale

updates / expansions to

existing flood hazard

mapping

➢ High quality base data

available (OMAFRA)

➢ Modeling software

advancements

➢ Regulatory Floodplain and

“inner lines” mapping

➢ NDMP – successful

application in Intake 4

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Introduction to the Project

➢ Between-the-banks

data required

➢ Why bathymetric

LiDAR?

➢ Limited information

available re: riverine

applications

➢ Discussions with

experts

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Considerations

➢ Timing

Season Pros Cons

Winter• Typically lower flows

• Lack of vegetation

• Typically ice covered

• Equipment constraints

Spring • Lack of vegetation • Higher flows

• Higher turbidity

Summer • Typically lower flows • Vegetation - in-water and above

Fall• Typically lower flows

• Lack of vegetation• Finite window

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Considerations

➢ Timing

➢ Contractor Availability / Willingness

➢ Cost

➢ Clarity / Turbidity

➢ Flow Depths

➢ Vegetation

➢ Physical Obstructions

➢ Permissions

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Trials & Tribulations

➢ Lack of Bidders

➢ Conflicting Schedules

➢ Uncooperative Weather

➢ Cloud

➢ Snow / Ice

➢ Rain

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Initial Results - Raw

Grand

River

at Paris

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Initial Results - Processed

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Initial Results - Processed

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Initial Results - Processed

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Initial Results - Processed

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Initial Results

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Initial Results - Processed

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Initial Results - Processed

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Initial Results

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Initial Results - Processed

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Next Steps

➢ GDS to finish processing operations

➢ Deliverables include:

• Raw data / point clouds

• Surfaces - TINs / DEMs

• RGB aerial imagery

➢ Modelling, modelling, modelling!

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Recommendations

➢ Know your watercourse characteristics

➢ Pre-consult with providers

➢ Provide quantitative data re: depths, clarity

➢ Plan ahead

➢ Larger-scale acquisition is preferred

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Questions?