Importance of QA in LiDAR Collects and Applications within Watershed Districts Presented to: North Dakota State Water Commission Bismarck, ND Presented by: Brian Fischer, CFM GIS Project Manager Jerry Bents, PE Vice President Mark Deutschman, PE, PhD Vice President June 4, 2009

Quality Assurance HEI under contract with International Water Institute to QA 45,000 sq. mi. collect in Red River Basin Includes all or Parts of 50 Counties Goal to provide an independent 3 rd party assessment and documentation on the quality of data

HEI under contract with International Water Institute to QA 45,000 sq. mi. collect in Red River Basin

Includes all or Parts of 50 Counties

Goal to provide an independent 3 rd party assessment and documentation on the quality of data

LiDAR Products (Hallock, MN) Bridge RAW Bare Earth Aerial Photo Hybrid Image

Hybrid Image

Acceptance Criteria Files are complete for delivery block Raw LAS, Bare Earth LAS, 1m GRID, Hybrid Metadata, Completion Report, Survey Report Root Mean Square Error (RMSE (z) ) of +/- 15 cm No major anomalies or data voids in visual assessment

Files are complete for delivery block

Raw LAS, Bare Earth LAS, 1m GRID, Hybrid

Metadata, Completion Report, Survey Report

Root Mean Square Error (RMSE (z) ) of +/- 15 cm

No major anomalies or data voids in visual assessment

Assessment Methodology Systematic check to ensure files are complete (Chain of Custody Form) Comparison between checkpoints and LIDAR product to calculate RMSE (z) Visual Assessment Data Voids Appropriate Classification Anomalies (spikes, penetration problems, etc.)

Systematic check to ensure files are complete (Chain of Custody Form)

Comparison between checkpoints and LIDAR product to calculate RMSE (z)

Visual Assessment

Data Voids

Appropriate Classification

Anomalies (spikes, penetration problems, etc.)

Quality Assurance (Checkpoint Survey) Checkpoints (approx. 1500) Minimum of 20 survey check points in dominant land cover class Landuse computed by Block Checkpoints collected in 5 land classes Low grass/bare earth High grass/weeds/crops Brush/low trees Forested Urban

Checkpoints (approx. 1500)

Minimum of 20 survey check points in dominant land cover class

Landuse computed by Block

Checkpoints collected in 5 land classes

Low grass/bare earth

High grass/weeds/crops

Brush/low trees

Forested

Urban

Quality Assurance (Visual Assessment) Anomalies, Systematic Errors, Human Errors Steps in flight lines, data voids, poor penetration, aggressive classification, misclassification

Anomalies, Systematic Errors, Human Errors

Steps in flight lines, data voids, poor penetration, aggressive classification, misclassification

Quality Assurance (Visual Assessment)

Quality Assurance (Visual Assessment)

Preliminary Results

Quality Assurance http://www.internationalwaterinstitute.org/lidar.htm

http://www.internationalwaterinstitute.org/lidar.htm

Importance of Quality Assurance Gives more confidence in the investment of the data Documents quality of data Serves as an acceptance mechanism for the contract History has shown LiDAR collects need validation IWI has rejected Block A and B for things found in the visual assessment (steps, data voids and missing files)

Gives more confidence in the investment of the data

Documents quality of data

Serves as an acceptance mechanism for the contract

History has shown LiDAR collects need validation

IWI has rejected Block A and B for things found in the visual assessment (steps, data voids and missing files)

Uses of LiDAR within Watershed Districts Preliminary Engineering Design and Planning Hydraulic Modeling Hydrologic Modeling Permit Reviews Risk Assessment Many Others

Preliminary Engineering Design and Planning

Hydraulic Modeling

Hydrologic Modeling

Permit Reviews

Risk Assessment

Many Others

Flood Control Impoundment Site Identification County Ditch 18 – Impoundment Example

County Ditch 18 – Impoundment Example

Flood Control Impoundment Site Identification County Ditch 18 – Impoundment Example

County Ditch 18 – Impoundment Example

Flood Control Impoundment Site Identification Pool at 1192.0

Pool at 1192.0

Flood Control Impoundment Site Identification County Ditch 18 – Impoundment Example Difference between Quad and LiDAR Data Less actual storage at each elevation 2–2.5ft high pool levels and embankment heights required to achieve same storage Approximately 50% increase in required land

County Ditch 18 – Impoundment Example

Difference between Quad and LiDAR Data

Less actual storage at each elevation

2–2.5ft high pool levels and embankment heights required to achieve same storage

Approximately 50% increase in required land

Hydraulic Modeling South Branch of the Wild Rice River – June 2000

Hydrologic Modeling Drainage Area Delineation Flow Length Time of Concentration Floodplain Storage Volumes Impoundment Site Volumes Wetland Storage Volumes Land Slope

Drainage Area Delineation

Flow Length

Time of Concentration

Floodplain Storage Volumes

Impoundment Site Volumes

Wetland Storage Volumes

Land Slope

Hydrologic Modeling

Hydrologic Modeling

Watershed Permit Reviews Existing Flow Patterns Assessment Area Contributing Area Slopes

Existing Flow Patterns

Assessment Area

Contributing Area

Slopes

Floodplain and flood insurance mapping DFIRM – Digital Flood Insurance Rate Map Production Hydraulic Modeling

DFIRM – Digital Flood Insurance Rate Map Production

Hydraulic Modeling

Risk Assessment Dam Breach Analysis at Rockwell Dam Storage Volume Inundation Area Topography/Cross-sections Watershed Delineation

Dam Breach Analysis at Rockwell Dam

Storage Volume

Inundation Area

Topography/Cross-sections

Watershed Delineation

Drainage Complaint Disputes Evidence of historic drainage patterns Complaint of Tree Removal and Filling in Natural Drain

Evidence of historic drainage patterns

Diversion Channel Routing Optional Alignment Analysis Quantity Estimates Cost Estimating R/W Requirements Hydraulic Analysis

Optional Alignment Analysis

Quantity Estimates

Cost Estimating

R/W Requirements

Hydraulic Analysis

Farmstead Ring Dike Design Alignment Quantities Cost Estimates Mitigation Requirements Permitting

Alignment

Quantities

Cost Estimates

Mitigation Requirements

Permitting

Off-site Wetland Delineation/Restoration Estimates USFWS – Restorable Wetlands NWI – National Wetland Inventory Contours Restoration Opportunities Mitigation Requirements Restoration Opportunities Potential Mitigation

USFWS – Restorable Wetlands

NWI – National Wetland Inventory

Contours

Restoration Opportunities

Mitigation Requirements

Lake Level Management Home Lake – Norman County Water Levels from Runoff Potential Outlet Modifications Permitting

Home Lake – Norman County

Water Levels from Runoff

Potential Outlet Modifications

Permitting

Watershed Applications Opportunities are endless Daily use since collection No more taping maps quad maps together

Opportunities are endless

Daily use since collection

No more taping maps quad maps together

Questions? Presented by: Brian Fischer, CFM GIS Project Manager Houston Engineering, Inc. [email_address] 762-493-4522 June 4, 2009