April 10, 2002 Jon KreischerCVEN GIS Identifying Critical Sewer Lines

April 10, 2002 Jon KreischerCVEN GIS Project Definition Identify Critical Sewer Lines in College Station –Necessary Step by Utilities Mngr –$3 million budget $1.9M Treatment $1.1M Collection Research CS Preventative Maintenance Capabilities & Strategies

April 10, 2002 Jon KreischerCVEN GIS Sewer Maintenance Historical Perspective –Reactionary vs. Proactive Strategies Cost Effectiveness –Material Type –Life Cycle Costs College Station –$3M Sanitation Budget, $1.1M for O&M of sewer collection system

April 10, 2002 Jon KreischerCVEN GIS Preventative Maintenance Types of Preventative Maintenance –Mechanical Sealing –External Grouting –Root Removal –Cleaning: Jet Rodding –Biological Agents: De-Greaser Bugs College Station’s Tools –Jet Rodding, Bugs, TV equipment

April 10, 2002 Jon KreischerCVEN GIS Critical Categories of Sewers Category A –High Impact System on surrounding environment –Post-failure Rehab is twice as expensive as planned replacement/four times cost of scheduled rehab –Require preventative maintenance Category B –Less critical than A because of reduced failure cost and effect. –Preventative action is still cost effective Category C –Non-critical Sewers –Preemptive Work in these sewers would not be cost effective

April 10, 2002 Jon KreischerCVEN GIS Critical Sewer Characteristics Old Age Deeper than average Clay pipes Located under busy streets Difficult access Located in Poor Soil Conditions Difficult to bypass Require Frequent Inspection or maintenance Near sensitive environmental area

April 10, 2002 Jon KreischerCVEN GIS Critical Sewer Lines in College Stations Large Lines – 13” or greater Busy Street – Texas Ave Require Frequent Maintenance –Vitrified Clay Pipe –Tree roots and grease

April 10, 2002 Jon KreischerCVEN GIS Original Sewer Lines Theme Sewer lines range from 4” to 32”. There is over 1.2 billion liner feet of sewer lines.

April 10, 2002 Jon KreischerCVEN GIS Sewer Line Attribute Table

April 10, 2002 Jon KreischerCVEN GIS Critical Sewer Lines - 1 Large sewer lines account for 1/8 of the network and include 215,000 liner feet of sewer lines.

April 10, 2002 Jon KreischerCVEN GIS Critical Sewers Lines - 2 Texas Ave is the primary road through College Station and Bryan.

April 10, 2002 Jon KreischerCVEN GIS Critical Sewer Lines - 2 The resulting Arcview Query identified only 14 of 4600 sewer segments that intersected Texas Ave. 6 of the 14 lines were larger than 13”.

April 10, 2002 Jon KreischerCVEN GIS Critical Lines - 3 6” – 8” clay lines account for nearly 1/2 of the entire line segments and over 500,000 liner foot of sewer lines.

April 10, 2002 Jon KreischerCVEN GIS The Project Continues Working with Manholes –Manhole Point Theme –Network Analysis Conclusions

April 10, 2002 Jon KreischerCVEN GIS Sanitation Work Force Preventative Maintenance Locating the Manholes

April 10, 2002 Jon KreischerCVEN GIS Any Questions