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