Creating a Water Utility GIS from the Aquifer Up

Robert P. Czaja, Sandy Elder, John Schiebold

Abstract
Tucson Water is a water utility that maintains 190,000 service connections over an area of 375 square miles. Working together with Esri and EMA, Tucson Water is creating an enterprise GIS using ArcGIS and the Geodatabase model. The GIS is being created by converting 1,527 atlas maps currently maintained using AutoCAD or paper. Integration with the utility's Maintenance Management System, Customer Information System and Hydraulic Model are three essential requirements of the GIS project. This paper discusses the processes and procedures being used to help ensure successful completion of this program.



Introduction
Background
Project Team
Software
Hardware
Data Conversion
Hard Copy Map Products
Integration
Security
Acknowledgements
Author Information



Introduction
Tucson Water is a department within the City of Tucson, Arizona. Our current customer base consists of approximately 675,000 people located in a 375 square mile service area. The physical water system consists of approximately 4,000 miles of pipe, 58,000 valves, 42,000 various fittings and 190,000 services.

Implementation of an enterprise Geographic Information System (GIS) is currently underway at Tucson Water. The goal is a digital, unified mapping process that meets the water system mapping needs of the department and allows deployment of this information into the field using hand held devices. Some of the obstacles confronting Tucson Water include:

This ongoing project is scheduled for completion during the second quarter of 2004.


Background
In June 1999, a GIS Strategic Plan was developed to address how an enterprise GIS could enhance and improve Tucson Water by making information more accessible. Also in June 1999, a Valve Map Conversion Report was written to assess the data and procedures that would be required to convert both paper maps and AutoCAD maps to a common digital format.

Tucson Water's existing paper-based mapping procedures maintain a map atlas composed of quarter-section maps called valve maps. These valve maps depict pipes and equipment of the water system, parcels, easements and customer connections. A complete set of quarter-section maps is termed a valve book. Each valve book currently contains 1,527 maps, each at a scale of 1 inch to 200 feet. Notes and corrections to the valve maps are recorded by staff in their valve books. Much of this information is never transmitted back to the mapping staff so that it can be included in future updates to the paper maps.

Tucson Water currently maintains our valve maps on both physical and digital media. At this time, 1,047 maps are on paper or linen and 480 are in an AutoCAD drawing format.

The current system of updating and distributing the valve maps is time consuming and inefficient. Updates to the valve books are produced quarterly and we estimate that over 3,000 person hours are spent each year replacing outdated valve book pages.


Project Team
Tucson Water has hired EMA, Inc. to assist with this project. Esri is serving as a sub-consultant to EMA. EMA has assisted with numerous aspects of the project including helping to define and document our business processes and workflows, selection of a conversion vendor, developing a conversion plan and creation of our ArcIMS site. Esri created our initial Geodatabase design and has helped assure that Tucson Water is properly prepared for conversion of our paper maps into electronic format. Synergen, manufacturer of our maintenance management software, is working closely with Tucson Water, EMA and Esri to link our GIS with their software.

Tucson Water is also working closely with Pima County which maintains much of the GIS data used on our valve maps including parcels, street names and various administrative boundaries.


Software
Tucson Water is committed to using Esri's ArcGIS and ArcIMS applications and the Geodatabase for the maintenance and display of our water system data. Our data is maintained in an Oracle 8i database using ArcSDE version 8.1.

Geodatabase Design
Our Geodatabase design was created using the Unified Modeling Language within Microsoft Visio 2000 Professional. Tucson Water currently maintains two UML models, one for our potable water system and a second for our non-potable water system. Esri constructed the first version of our models. Tucson Water staff has attended Geodatabase design training conducted by Esri and now maintains and updates both models in-house.

ArcGIS
Approximately 30 of our staff will access the data using ArcView, ArcEditor, or ArcInfo. These individuals need the ability to edit the data or to perform spatial analyses.

ArcIMS
Approximately 200 Tucson Water employees will access the data using ArcIMS. These individuals are the primary users of the valve books and do not need the ability to perform editing or spatial analyses.

EMA, working together with Tucson Water staff, has developed a custom ArcIMS application using the Java viewer. One requirement of the ArcIMS site was that it provide a method for Tucson Water personnel to submit feedback to our mapping staff. The Java viewer was selected because it supports the use of redlining tools. Redlining tools allow the map view to be annotated with graphics and text to indicate field conditions that differ from those represented in the database. The annotations are submitted electronically to the mapping staff that maintains the Geodatabase. The identity of the user submitting the change is tracked so they may be contacted in the event that additional information is required.

Using ArcIMS to deliver the water system data to the majority of our employees simplifies administration of the software and decreases software purchase and maintenance fees. A wide range of Microsoft operating systems, including Windows 95, Windows 98, Windows NT and Windows 2000 are in use at Tucson Water. Use of a Web based application to provide access to our water system data decreases our hardware costs since the application will run on all of the personal computers currently in use at Tucson Water. This is an important consideration since funds available for computer replacement vary widely across departments.


Hardware
Tucson Water is using three Compaq servers for our GIS related applications. Windows 2000 Server is the operating system for all three servers. Oracle 8i, version 8.1.7 and ArcSDE 8.1 are running on a single server with the following configuration:

The twelve hard drives are separated into six, two disk logical drives each using RAID 0+1. Each controller card controls six physical hard drives. The database files are distributed across the six logical drives to minimize disk contention.

Two servers are used for the ArcIMS application. Each of these servers is configured as follows:

The four hard drives are combined into a single logical drive using RAID 5.


Data Conversion
The primary goals of this project are to overcome obstacles inherent in the existing paper based system, and allow integration with other information systems used by Tucson Water. A key step in achieving these goals is the conversion of existing paper based valve maps into an Esri Geodatabase.

Conversion Plan
Tucson Water, together with EMA and Esri, has prepared a Valve Map Conversion Plan specifying the methodology and requirements to be followed during the conversion process. The conversion plan outlines the following items:

Tucson Water considered both in-house and outsourced conversion of the paper valve maps. Based on our resource limitations and time constraints, the decision was made to outsource the conversion.

A Request for Proposal (RFP) was issued which included much of the information contained in the Conversion Plan and the City of Tucson’s requirements for procuring outside vendors. Ten prospective vendors submitted proposals, three of which were short-listed. The short-listed firms were required to give presentations on their proposals and participate in an interview process with our selection committee.

The top-ranking firm was notified on June 21, 2002. Tucson Water expects to complete contract negotiations by the end of June 2002.

Delivery of Converted Data
Tucson Water is taking an active role in the conversion of the valve map data. Our staff is pre-scrubbing the source maps, inspecting the delivered products for quality and supporting on-going communication with the vendor. The conversion vendor is responsible for delivering the spatial data as well as other supporting deliverables. We estimate that conversion of our valve maps will take 12 to 18 months.

We have divided our service area into seven separate areas for conversion. Accepting a single delivery of all 1,527 converted valve maps would overwhelm Tucson Water staff and prevent meaningful feedback to the vendor in the event of errors or unacceptable data deliveries. Also, the time lag between delivery of data and feedback from Tucson Water would have made problem resolution difficult for the vendor.

Tucson Water anticipates performing quality control on each data delivery using Esri’s Production Line Tool Set GIS Data ReViewer. This software allows Tucson Water to ensure the Geodatabase schema has remained consistent throughout conversion activities and that features have been attributed correctly. Quality control activities will be performed in an Oracle instance separate from the production environment. Once the quality control activities have been completed and the data delivery accepted by Tucson Water, the dataset will be loaded into the production environment and made available to Tucson Water staff.


Hard Copy Map Products
Tucson Water field crews, system planners and customer service employees depend on ready access to accurate water system data to perform their jobs. Although we anticipate that in the future most employees will gain access to the water system data via the GIS, we expect Tucson Water will always have a need for hardcopy maps. Access to hard copy maps ensures our data will be available to our staff and customers regardless of hardware or software problems.

The current paper water system maps are widely accepted both within Tucson Water and the community. A major goal of this project is to produce paper maps from the GIS that maintain as much of the look and feel of the existing maps as possible. This places a greater responsibility on the persons developing the GIS, but makes it easier for the user community to adapt to the new maps.

Symbology
A custom symbol set that mimics the existing symbols used on the paper maps is being created. This allows users to adapt to the new maps in the least amount of time and helps prevent misinterpretation of the data due to changes in symbology. Creation of the symbols is relatively straightforward. Tucson Water utilizes the Fontographer software package to create custom symbols.

Symbol sets are being created using True Type fonts. We anticipate that sections within Tucson Water that depend on AutoCAD will be able to use these symbol sets. From a utility wide perspective, this is desirable since it allows using a consistent symbol set regardless of the software platform. Slight variation in the symbols may be necessary for the ArcIMS application to improve readability on a computer monitor.

We are attempting to make all symbols unique without relying on color. This allows the paper maps to be printed on standard printers or photocopied without the loss of information. This is proving to be a challenging task given the number of unique symbols that are required. Users viewing the electronic version of the data will have the advantage of color. Our expectation is that over time, users will begin to prefer the electronic data because color conveys the information contained in the map more easily than line type or shape alone.

Annotation
Tucson Water's existing maps contain a significant amount of annotation. Annotation is problematic because it must be placed by hand to prevent conflicts with other symbols, labels or features. Tucson Water is relying on symbology rather than annotation wherever possible. One example of this is our closed valves. Currently a closed valve is indicated with the letters "CV". We have eliminated the need for this annotation by creating a symbol that indicates the valve type and its state, i.e. open or closed. Feature linked and plain annotation will be used to print paper valve maps from the Geodatabase.

Details
Our existing paper maps make use of details to clarify complex areas of the maps. Details are not necessary in the GIS because the user can zoom into an area to reveal details that may not be visible at smaller scales. Tucson Water is seeking a method that allows creation of the details for the paper maps without the need to maintain a layout file for each of our 1,527 maps.


Integration
Tucson Water’s human and financial resources are fairly static while our customer base increases by approximately 6,000 new services annually. To continue to provide our customers the high quality of service they expect, it has become critical to find ways to increase efficiency. A key element in this effort was to acknowledge that our current business processes could be greatly enhanced by leveraging technology. We have always understood that our business processes could never be completely replaced by technology, but the automation of many of these processes would help our staff keep up with their ever increasing workload and still provide our customers with outstanding service.

The GIS at Tucson Water has never been viewed as a stand-alone application to be used only for keeping valve map data current. Rather, GIS is one component of an enterprise system that will provide us the capability to enhance the way we do business. Key systems that we have chosen to integrate GIS with are our Maintenance Management System, Customer Billing System and Hydraulic Modeling software.

Maintenance Management System
The Maintenance Management System (MMS) helps us manage work orders and maintenance related to our assets. In the context of the MMS, Tucson Water defines an asset as objects that require maintenance. The integration of MMS with GIS allows us to not only manage the maintenance of our assets, but also provides the capability to locate the assets spatially. Staff working in the MMS will be able to locate assets on a map from within the MMS software. Staff working in the GIS will have access to attribute information stored in the MMS directly from the GIS software.

Several MMS packages were evaluated before we selected a product. Many of the products we evaluated suited our needs from a maintenance perspective, but were not tightly integrated with Esri products. During our selection process, the Synergen product met our requirements from a maintenance perspective, as well as provided a high level of integration with Esri products.

While documenting our business processes related to GIS and MMS, it became apparent that each of our assets has many properties or attributes. It also became apparent that some attributes were better maintained in one system or the other. For example, users of the GIS may be interested in the location of a well, but not in knowing the last time the pump motor was replaced.

This realization led to a discussion of data stewardship. Parties responsible for maintenance of each attribute were identified, and decisions were made regarding which system would be the system of record for each attribute. In general, assets and any related attributes that appear on the existing valve maps are maintained in the GIS and the remaining assets and or attributes are maintained in the MMS.

Though some attributes are stored and maintained in one system and not the other, we still needed to see the data in both the MMS and GIS. Maintaining a primary/foreign key relationship between the MMS and GIS databases supports this functionality. The primary key is generated in the MMS using an Oracle sequence. The primary key is then posted back to the GIS database as a foreign key. Tucson Water is working with Esri and Synergen to script this process so that it may be performed on a regular basis as a batch process.

Tucson Water anticipates that we will make use of the Geodatabase’s versioning capabilities. We plan to link only the SDE Default version to the MMS since this is the only version that will be made available for general distribution.

Customer Billing System
Not only is it important to have current information about our physical assets, it is also critical for us to maintain information about the customers connected to them. Tucson Water uses a suite of applications produced by HTE Inc. to maintain our customer information. The HTE software stores data in a proprietary format that is not easily integrated with other systems. To resolve this issue the vendor created a custom script that exports billing system information into a formatted text file referred to as a shadow file. The customer location and service identification fields form a composite primary key in the shadow file. These fields have been included as foreign keys in the Service feature class in our Geodatabase.

Hydraulic Model
Tucson Water currently uses WaterCAD software developed by Haestad Methods Inc. to perform hydraulic modeling. Data used in the hydraulic model before the implementation of GIS was a simplified version of existing valve map data. GIS data for use in our hydraulic models was stored in two shape files commonly referred to as our node and link files. The node and link shape files required constant maintenance to keep them in sync with changes to the valve maps.

With the upcoming release of Haestad’s WaterGEMS product, we anticipate a tighter integration between our Geodatabase and hydraulic models than is possible with the current system. An additional benefit will be that the node and link datasets will become obsolete, freeing staff for other tasks.


Security
The events of September 11, 2001 have impacted the original scope of this project. Our initial intent was to make the water system data available to other City of Tucson employees and possibly the general public via the Internet. Our current intention is to provide access to the complete water system data only to Tucson Water staff. A data layer indicating which land parcels are serviced by Tucson Water may eventually be provided to the business and real estate community via the Internet. This layer would only indicate that water service is available, not the locations of water pipes.


Acknowledgements
The authors wish to express their thanks to Bryn Enright, Virginia Carroll and Ann Youberg for their valuable assistance with this paper.



Author Information

Robert P. Czaja, GIS Systems Analyst
City of Tucson
Tucson Water
POB 27210
Tucson, AZ 85726-7210
bczaja1@ci.tucson.az.us

Sandy Elder, Project Manager
City of Tucson
Tucson Water
POB 27210
Tucson, AZ 85726-7210
selder1@ci.tucson.az.us

John Schiebold, Senior Consultant
EMA, Inc.
1970 Oakcrest Avenue, Suite 100
St. Paul, MN 55113
jschiebold@ema-inc.com