Arkansas Administrative Code › Agency 229 - Ar Geographic Information System Board prev State Land Information Board › Rule 229.00.18-001 - Revisions to Arkansas Centerline File (ACF) Standard

Current through Register Vol. 49, No. 6, June, 2024
Introduction
The State Land Information Board, now the State GIS Board,
			 developed this document in order to support the legislative initiatives to
			 establish the Arkansas Spatial Data Infrastructure (Arkansas Code 15-21-5 ).
			 Spatial data layers are often stored digitally and accessed through a
			 relational database management system (RDBMS). Although the centerline file is
			 a component of the Arkansas Spatial Data Infrastructure, the way in which
			 people format and maintain it can differ. People often disagree on the way a
			 particular spatial data layer structure should be organized. This can pose
			 problems in terms of sharing, locating, and extracting spatial data
			 information. It is intended that these standards will benefit the Geographic
			 Information Systems (GIS) user communities in numerous ways, including but not
			 limited to:
The National Map Program1, The
			 TIGER Modernization Program2
, E-911
			 applications, routing services, and location dependent services.
The following standards specifically speak to methodologies for
			 creating a seamless statewide Arkansas Centerline File with address ranges that
			 are shareable, geocodable, and have a horizontal accuracy better than 10
			 meters.
Background
The State Land Information Board (SLIB) was created by Act 914 of
			 the 1997 General
Assembly and is responsible for:
* Identifying problems and solutions in implementing a spatial
			 data repository
* Developing and coordinating a schedule for state spatial data
			 projects
* Recommending methods of financing for state spatial data
			 projects
* Providing educational programs that are focused on spatial data
			 technologies
* Coordinating collaborative projects
* Establishing spatial data standards (Section
			 4. (f) (1) of Arkansas Code
			 15-21-5 ).
Act 244 of 2009 renamed the Board to the State GIS Board.
Arkansas Code 15-21-5 An Act to Amend the Arkansas Code to Create
			 the Geographic Information Office and Establish the Arkansas Spatial Data
			 Infrastructure and for other purposes establishes these SLIB principles:
* Validity, consistency, comprehensiveness, availability, and
			 currentness of data are essential components of all automated land information
			 systems.
* Coordination with federal, state, regional, county, and
			 municipal agencies, state universities and colleges, private firms, and others
			 who require the same spatial data will reduce duplication of efforts and
			 expense.
* Creation of new data in an accurate and usable format in
			 accordance with the states shared technology architecture will ensure
			 availability across state agencies.
Purpose
This standard is intended to make centerline files more uniform
			 and horizontally accurate. This will facilitate the sharing of a statewide
			 seamless centerline spatial data layer. Adhering to these standards will insure
			 the "usability" of the spatial data theme and its attributes by multiple
			 entities. This standard will insure a consistent manner in which the centerline
			 and/or attributes are collected. This will enable the data to be merged
			 seamlessly, and transferable regardless of creator or jurisdictional
			 boundaries. All data used in the creation of the Arkansas Centerline File shall
			 meet these standards.
*Note: Throughout the remainder of this document ACF shall refer
			 to Arkansas Centerline File. This includes the vector spatial data layer and
			 its attributes. The ACF shall be composed of centerline files created from
			 multiple sources and/or entities. Centerline shall include all clearly defined
			 passages through which a standard vehicle may travel as well as driveways
			 extending more than 500 feet and/or driveways containing two or more addressed
			 structures.
Technical Practices for Creating ACF Vector Layer
			 geometry
ACF Feature Type:
Vector lines shall be used to represent centerlines. The ACF
			 shall "seamlessly" match across jurisdiction boundaries (i.e., cities,
			 counties, etc.). Address ranges shall be organized along the linear feature to
			 support address geocoding. The address ranges shall be stored within the
			 centerline attribute table of the geospatial dataset.
Topology:
The centerline file shall be processed using appropriate GIS
			 procedures to create and maintain accurate topology, if intended for
			 incorporation into the ACF program. In order to eliminate common dangle and
			 intersect topological errors, care should be taken while digitizing to snap the
			 endpoints of line centerline segments to endpoints of other line segments. At a
			 minimum the following topology rules should be adhered to:
Click here
			 to view image
Click here
			 to view image
*
Topology rules excerpted from
http://resources.esri.com
.
Inclusion of Specific Geometric Elements:
In order to support the development and ongoing maintenance of
			 the all public roads linear referencing system, otherwise known as the All
			 Roads Network Of Linear Referenced Data (ARNOLD,
			 http://www.fhwa.dot.gov/policyinformation/hpms/arnold.cfm), geometric elements
			 representing particular road design types should be digitized in the ACF vector
			 layer. Practices for digitizing these elements can be found in the subsequent
			 Digitizing section.
1. Dual
		  carriageway routes
2. Single
		  carriageway
3. Connector
		  segments
4. Traffic
		  circles
5. Grade separated access
		  ramps
6. At-grade access
		  ramps
7. Frontage roads
8. Highway facilities
Digitizing:
Centerline files intended for incorporation into the ACF program
			 may be produced utilizing heads-up digitizing techniques. Heads-up digitizing
			 methodologies used may include, but are not limited to, point mode, stream
			 mode, spaghetti mode, or increment mode. Heads-up digitizing should be
			 performed utilizing the following standards.
Capture scale should be 1:1,200
Projection - UTM Zone 15
Datum - North American Datum 1983 (NAD83)
Units - Meters
Source - At a minimum, the second Generation Digital Ortho
			 Quarter Quadrangles
(DOQQs) that have verified horizontal accuracies should be used.
			 However, the best available imagery should always be used given that many
			 jurisdictions have acquired their own aerial imagery since the acquisition of
			 the state DOQQs mentioned above.
Best practices should always be adhered to when digitizing
			 features in the ACF vector layer. These shall include, but may not be limited
			 to the following:
1. All
		  linear road features representing public or private roads that have been given
		  a name and left/right range values for addressing purposes should be properly
		  segmented into individual features at intersections representing transportation
		  decision points and snapped to endpoints to ensure proper topology. If an
		  existing road feature is split to create proper segmentation, the left and
		  right addresses ranges should be recalculated to reflect the change in
		  geometry. The exceptions to this would be but are not limited to:
a. Where the local jurisdiction digitizes
		  driveways for location purposes and does not name or range them for
		  addressing.
b. Where two road
		  centerline features intersect and do not represent a transportation decision
		  point, e.g. an overpass or underpass where direct travel between the roads is
		  not possible. Centerlines should not split (segmented) at these
		  locations.