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Data Acquisition 
       
    
     
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Preprocessing 
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BUILDING 
OUTLINES 
Manipulation and Analysis 
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BASE MAP 
  
Figure 1. Spatial information 
Product Generation 
  
  
  
  
layering concept 
surveying can be used to develop the coordinate 
base map. The coordinates of key points on the 
ground, such as parcel corners, points along 
centerline of a road are determined by GPS and 
design maps with dimensions. These 
coordinates are entered directly into computer 
graphics file. These points are then connected 
with lines or arcs to form the base map required 
in GIS. Unfortunately, subdivision maps and 
road design maps do not give elevations and the 
location of buildings. Utility maps are tied to fire 
hydrants, power and telephone poles, etc; thus, 
in order to add the utility maps to the coordinate 
base maps, the location of the fire hydrant, etc. 
must be determined. Fortunately digital 
photogrammetry using large scale aerial 
photography can be used to precisely locate 
buildings, fire hydrants, telephone posts, power 
poles and elevations of points on the same base 
map coordinate system and build the GIS for the 
city. 
Roland, lowa was selected as the project city for 
several reasons. With a population of about 
1,000 people, Roland is large enough to have a 
city utility department which provides water, 
sewer and street maintenance for the town. 
Roland’s corporate boundaries lie directly along 
lines connecting U.S. Public Land Survey 
Monuments (See figure 3). All subdivision maps 
and land parcels are tied to U.S. Public Land 
Survey Monuments known as section and 
quarter section corners. Using GPS the locations 
of survey monuments can be determined 
precisely on a World Geodetic System (WGS). 
The dimensions of subdivision, parcel and other 
design maps are in surface horizontal distances. 
In U.S.A. State Plane Coordinate systems are 
used as the projection coordinates at the state 
level. Universal Transverse Mercator (UTM) is 
the projection system for the entire country. Thus 
for a city, it is desirable to have the base map 
628 
Figure 2. The five elements of a GIS 
coordinate system in a surface State Plane 
Coordinate system. The city of Roland had a 
base map prepared in 1983. They have copies of 
the subdivision plats, plans and profiles of 
streets and utilities. Attribute data such as 
parcel ownership or current assessed values are 
also available from the Story County assessor. 
Thus, by definition, Roland has a manual GIS. 
The objectives of this paper are to describe the 
procedures developed in creating a modern 
automated GIS for Roland, lowa under the 
following headings: 
(1) GIS Applications for a City 
(2) Ultimap GIS Software 
(3) Base Map Coordinate System 
(4) Development of the Base Map 
(5) Data Acquisition Techniques 
(6) Building GIS 
GIS APPLICATIONS FOR A CITY 
A GIS for a city should provide a minimum of two 
capabilities. First, the capability to store, 
retrieve and display attribute data pertaining to 
graphical entities. More specifically, one should 
be able to view a map of the city, select an entity 
with the cursor and have the system display 
attribute data pertaining to that entity. Secondly, 
the GIS should have the capability to analyze an 
existing attribute data file and indicate all 
graphical features which meet a particular 
attribute description provided by the user. 
Two subdivisions, Britson, Second Addition and 
Ryan, First Addition, which meet all the 
requirements of a city, are selected as the study 
area. The specific attributes available for 
processing differed between the two 
subdivisions of the project. The information 
available in Britson’s Second Addition would be 
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