Iowa DOT LRS
Steve Kadolph
Research & Technology Bureau
Highway Division
Discussion Topics
• What is the LRS
• Data collection status
• How is the DOT using it
LRS Team Recommendations• Need to improve spatial representation
• Use NCHRP (20-27) project model
• Need ability to integrate variety of data– Mile post referenced data (US 30 @ 135.23)– Coordinate referenced data (Lat, Long, I35)– Literal description data (2.51 mi past 1st St)– Road address data (247 E. Main St)
• Need to provide a navigable network
• Establish maintenance processes and partnerships
What is the LRS?
LRS - Linear Referencing Systema set of procedures and methods for specifying a location as a distance, or offset, along a linear feature, from a point with known location
LRM - Linear Referencing MethodDifferent methods of measuring linear locations; (i.e. milepoint, literal description, address range, etc.)
LRS Model
LRS Components
CoordinateRoute
ReferencePost
CoordinateRoute
Milepoint StationingLiteral
Description
BaseRecordCrash PMIS Inventory Project
DataProgram
CenterlineRepresentation 2
CenterlineRepresentation 3
CenterlineRepresentation 1
AddressRange
Linear ModelingIntegration Between Different
LRMs
Integration of data stored in different LRMs creates a need for many transforms or cross-reference tables.
LRM
LRM
LRM
LRM
LRM
LRM
Transform
Transform
Transform
Applying the LRS Technology Architecture
Eth
erne
t
LRSRun-time
Server
HTML Clients
Eth
erne
t
CAD and GISWorkstations
LRSMaintenance
Server
Legacy System Mainframes
HTML Client
SQL Terminal
LRS Maintainers LRS UsersDatabase andApplication Servers
Mobile Clients(Palms, DGPS, DMI)
MobileClients
Basic and RobustWorkstation Clients
Mobile Clients
INTRANET
Mobile ClientsINTERNET
LRS Thin ClientApplication Server
Firewall
LRS Maintenance/Development Server
LRS DeveloperWorkstations
Lin
ear B
usin
ess
Data
Part of DSE
Decision Support Environment System Architecture for Integrating Data
Staging Process
Crash Records
PMIS
Bridge
GIMS
General DecisionSupport
CTAMS
PMIS
Sufficiency
Web CTAMS
Specific AnalysisSystems
GeoData
Lib
rary
LRS Maintainer
Derived Data Valuesfrom Integrated Data
Derived Data Valuesfrom Integrated Data
LRS
GIS Maintainer
GIS
LRS Components
• Roadway Shape – Cartographies• Datum - Anchor Points/Anchor Sections • Network - Transport Nodes/Transport Links• Routes – E911, State, County, Municipal,
Private, Institutional, Unofficial, Ramps• LRM Components – Reference Posts, etc.
What the LRS Looks LikeCartography
Road Network
What the LRS Looks Like
AnchorPoint
Cartography
AnchorSection
Road Network
What the LRS Looks Like
AnchorPoint
Cartography
AnchorSection
TransportNode
TransportLink
IA 507
Road Network
What the LRS Looks Like
AnchorPoint
Cartography
AnchorSection
TransportNode
TransportLink
Route
IA 507
Road Network
Elm St
What the LRS Looks Like
AnchorPoint
Cartography
AnchorSection
TransportNode
TransportLink
Route
IA 507 ? ReferencePost
5
4
Road Network
Data Collection Status
LRS Features Created
• Anchor Points (139,829)
• Anchor Sections (80,163)
• Transport Nodes (215,764)
• Transport Links (313,117)
• Routes (113,380)
• Reference Posts (11,701)
114,000 Miles Public Roads in LRS
LRS I 35/80/235 Ramps
GIMS 2002 LRS Accuracy
Local Road GIMS/LRS
Data CollectionI-80 Adair Dallas
Anchor Sections
Transport Links
Routes Assigned
Reference Posts
How is the DOT using the LRS?
Applying the LRS Decision Support Conceptual Model
Business Data
PavementBridge
Road InvCrashes
Rail...
Safety Inv
OperationalComponents
DatumNetworkRoutesProjectsMetadata
LRMs
Ref PostCoor RteLit Desc
MilepointStationingSegmental
GeoDataLibrary Data
LRS Op CompLRM
EnvironmentalDesign
CadastralAerial Photos
Satellite Images
PavementBridge
Road InvCrashes
RailSafety Inv
LRSStaging
Linear/Spatial
Relationships
Linear/Spatial
Relationships
Linear Referencing System
Business Data Staging
CTAMS Analyst GeoMedia or GeoMedia Pro
How Does the DOT Benefit
How Does the DOT Benefit
Partnering Benefits
• Provides a centralized data storage facility and data source for most road transportation information systems
• Minimizes redundancy• City Government (Utilities, Engineering)
• County Government (Engineering, Assessor)
• State Government (DOT, Emergency Mgmt)
• Federal Government (Census, FHWA)
What Is Required to Use the LRS
• Reference Post LRM (MilePost)– Route System (Interstate, US, Iowa)– Route Number (29, 65, 151, etc.)– Reference Post (1, 2, 3, 3A, etc.)– Offset (+/- distance from observed Post)
• Coordinate Route (GPS)– Coordinates (Latitude, Longitude)– Route System and Number (ensures correct route
selected in dense road networks)• Temporal Component (mm/dd/yy)
Technical Infrastructure
• Production Oracle database with Spatial– Dual Processor 4GB RAM– Oracle workspace manager– Bentley LDMx– GTM
• Test Oracle database with Spatial– Shared VM Server– Oracle Workspace manager– Bentley LDMx– GTM
Technical Infrastructure
• Over 650 Tables and 4000 views
• Ability to use GIS Software or custom SQL queries to view data.– select anchor_section_id,
utility.GET_CONFLATION_GEOMETRY(CONFLATION_GA_TW), geometry_ga_tw from ANCHOR_SECTION where anchor_section_id = 58515