SEWER SYSTEM MAPPING At Wells Sanitary District

In recent years. portions of southern Maine have experienced a great deal of growth. To accommodate this growth. the areas infrastructure has undergone a variety of upgrades and improvements.

As the sewered area in Wells has grown. it became apparent that the record drawings spanning decades of improvements and additions were no longer adequate for tracking the system.

With this in mind, the Wells Sanitary District hired Wright-Pierce to develop composite mapping of the system. The first step in this effort was to assemble the variety of documen­tation that had accumulated over the years. detailing the various portions of the system. The various sewer contract areas were overlaid on a GIS based road map provided by the town.

This preplanning helped to establish a systematic approach to the field work, minimizing equipment downtime, necessary for generating a detailed and accurate map of the system.

The actual survey work was accomplished with a survey grade. backpack mounted, GPS receiver and data collector. The majority of the field work was done in the early fall. Due to dense ground cover in some cross country portions of the system, poor reception, and difficulty in locating some of the structures, resulted in final survey work being completed in early winter when vegetative cover was not as dense.

The resulting GPS data was differentially corrected and compiled to generate an overall system map. Line work was completed in AutoCAD with pipe details attached. These drawings were then imported into Arcview and additional data was added based on the record drawings. The final product is a GIS based map of the sewer system with data tables detailing the system components. As further inspections and maintenance of the system takes place, additional data regarding structures and conditions can be added to the data tables. This will allow the system operators to maintain detailed records of the Wells Sewer System.

Project Manager for Wright-Pierce was Peter C. Atherton, Mark A. Vannoy was the Project Engineer and Linwood A. Bailey, Manager of GIS Services at Wright-Pierce, was re­sponsible for GIS technology.