Making Maintenance Manageable

Rob GainesSenior GIS Analyst, Zimmerman Associates (FEMA Ctr)

April 18th, 2012

Using FME to Maintain FEMA’s National Flood Hazard Layer

What is the NFHL?

FEMA’s National Flood Hazard Layer, part of the National Flood Insurance Program.

Nationwide regulatory GIS dataset used to communicate flood risk information.

The Numbers

Compiled from 2081 individual community or countywide flood study datasets (and growing).

Average 95 county/communities updated per month.

32 spatial layers, 18 lookup tables.

Over 85 million records in total.

How is the NFHL Accessed?

MapViewer: 100,000 – 200,000 requests per month.

KMZ/WMS: 3 – 6 million requests per month.

NFHL Extract (via state shapefiles).

What is the NFHL?

What is the NFHL?

What is the NFHL?

What is the NFHL?

FIRM/NFHL Production Structure

FIRM DatabaseCounty Dataset

PTS rFHLRegional Dataset

CDS NFHLNational Dataset

FIRM/NFHL Production Structure

Data Going Effective 4/3/2012

Challenges

Data produced at community level.

Initial QA/QC process not intended for NFHL.

Bureaucracy: 10 exceptions to every rule.

Far removed from data producers.

Inherited systems.

What Is FME Used For?

QA/QC of data submissions.

Data replication.

Extraction.

Report generation / tracking.

LOMA Point creation.

Basic QA/QC Checks

All records have DFIRM_ID value. All required layers are present. No duplicate geometry. Flood hazard lines & areas have valid flood zone

values. Effective date information is correct. New data contains all currently effective LOMRs.

QA/QC FME Model

QA/QC: DFIRM_ID Value

Uses FeatureMerger transformer to check that all records have DFIRM_ID value and all DFIRM_ID values match a record in the STUDY_INFO table.

QA/QC: Required Layers

Uses ListPopulator and ListExploder along with FeatureMerger to create a list of all layers present in submission and then check them against the list of required layers.

QA/QC: Duplicate Geometry

Concatenates a number of geometric attributes (such as coordinate count, length / area, etc) with flat attributes to detect duplicate features and filter them out.

QA/QC: Valid Values

Uses the AttributeFilter to detect any invalid flood zone values.

QA/QC: LOMR Checker

Compares submission LOMR layer with current NFHL LOMR layer to detect any missing information.

Sample QA/QC Sheet

Data Staging & Replication

NFHLData

NFHLData

NFHLData

StagingDB

FMELogger

LogDB

MS Access Interface

NFHL SDEFME

Loader

FME Replicator

StagingLoad Model

StagingLoad Model: Logger

Replicator Access Query

Replicator Access Form

Extraction

Extract all NFHL records into state-based shapefiles.

Generate reports such as panel and LOMR count for each state.

QC: Check current extract against prior extract to ensure completeness of layers.

Extraction: QC FME Model

Runs through each state extract.

Uses ListBuilder to build a list of each state’s layers and check them against previous month’s.

Generates Excel report.

Extraction: QC Sheet

Reporting & Tracking

Inventory of current NFHL holdings.

Status of currently effective LOMRs.

QC of existing NFHL data. Missing layers. Invalid values. Obsolete data.

NFHL Inventory Report

NFHL LOMR Status Report

LOMA Mapper

Daily process which converts flat data with lat/lon attributes to geospatial data in SDE.

Replaced custom-developed VB application.

Original application: 18+ hour runtime.FME Model: <10 minute runtime.

LOMA Mapper Flowchart

LOMA Mapper FME Model

Into the Future… FME Server

Internal Automated data submission & QA/QC process.

External Clip/Zip/Ship via MapViewer. Custom extracts. Custom on-demand GIS services.

Thank You!

Questions?

For more information: Rob Gaines: robert.gaines@riskmapcds.com

Zimmerman Associates Inc. (FEMA Contractor)

FEMA Map Service Center: http://msc.fema.gov