Integrating GIS with utility Information management Systems
After much internal discussion, OES made the decision not to update its master infrastructure database
directly from the GIS environment. This is due to an organizational preference rather than software
functionality limitations. As new features are added to, or existing features edited in, the GIS maps,
changes will be made to the master infrastructure inventory database using the CASS WORKS software
interface independently of the changes to the GIS database. Procedures will be implemented to noti@
those staff responsible for maintaining CASS WORKS of any changes. These procedures will need to be
rigidly followed so that changes to the infrastructure inventory database and GIS are properly
synchronized. These procedures will require close coordination between the operating and engineering
divisions as they will have co-responsibility for the maintenance of the master infrastructure database
and GIS.
Figure 2. Information Flow between Master Database, GIS, and Hydraulic Models.
To mitigate data access problems on the current OES LAN, a copy of select tables will be downloaded
from the master infrastructure inventory Oracle database located on a file server in the OES operations
division to the local GIS file server located in the OES engineering division. The copy of the
infrastructure database will be stored in an INFO format for rapid data retrieval in Arc/Info and Arcview.
Data not accounted for in the master infrastructure inventory database, yet required for mapping and
modeling, are stored in “supplemental tables” in an INFO format. These “supplemental tables” reside
outside of the realm of CASS WORKS and are updated directly from the GIS. Automated applications
using Oracle SQL and Arc/Info AML are being developed to maintain these data and to verify referential
integrity between the CASS WORKS tables and the supplemental tables.
When OES engineering division updates its hydraulic models, modeling attributes are downloaded from
the CASS WORKS infi-astructure inventory database and the network representations (graphics) are
downloaded from the GIS. Applications developed using Arcview/Avenue automate this procedure and
ensure proper synchronization between the attributes and the graphics during model data preparation,
warning OES staff of any inconsistencies noted during the data preparation process. Both modeling
software applications, H20NET for water and Hydroworks for wastewater, contain powerful data
display, query, and specialized analysis tools, therefore providing all necessary functionality for review
and analysis of modeling results and eliminating the need to upload model result data back to the master
infrastructure inventory or GIS databases.
Methodology
Several challenges arise when moving data between an infrastructure inventory database with a
prescribed data structure and conceptual representation of water/wastewater system facilities, a GIS
environment where the primary goal is cartographic reproduction of existing paper maps, and hydraulic
models with their own prescribed data structures and waterlwastewater facility representations.
Linkina GIS to the CASS WORKS Infrastructure Inventory Database
Of primary importance was adhering to the goal to store all data in CASS WORKS that the OES CASS
WORKS database is configured to store, and to store additional information in supplemental database
tables. As a result, some GIS features are linked to records in one CASS WORKS table, other GIS
features are linked to records in numerous CASS WORKS tables, and still other GIS features are linked
to records in CASS WORKS and in supplemental tables, depending on which tables were configured to
store specific information.
For example, an air release valve in the GIS is linked to a record in the CASS WORKS Valve Inventory
table only, whereas a flow control valve in the GIS is linked to a record in the CASS WORKS Valve
Inventory table and a record in the CASS WORKS Node Inventory table. The CASS WORKS Node
Inventory stores information required for hydraulic modeling, and the CASS WORKS Valve Inventory
stores information specific to valve facilities required for GIS mapping, yet not required for modeling.
Air release valves are not being modeled, whereas flow control valves are being modeled and therefore
flow control valves contain a record in the CASS WORKS Node Inventory while air release valves do
not. Additional database table combinations exist for each of the approximately 30 water/wastewater
facility types represented in the GIS database.
To mitigate the potential loss of productivity as OES staff attempt to navigate a comprehensive and
sometimes complicated database structure, OES and Montgomery Watson are developing custom GIS
applications to facilitate data retrieval during routine GIS display and query operations. These
applications, developed using Arc/Info AML and Arcview Avenue, will facilitate data retrieval so that
OES staff can focus on examining data rather than trying tojkzd the requested data, which would
otherwise be a lengthy, difficult, and frustrating task. The majority of OES staff will be trained on the
use of the GIS software applications rather than on the internal database structures.
