Knowing the source of On-Site Sewage: Methodologies and Challenges to Manage a Real-Time Spatial Database. Conference Paper uri icon


  • In Texas, on-site sewage system facilities (OSSF) systems are very common, due the low density of houses in many parts of the State. OSSFs are often installed and almost forgotten, as the effects of poor maintenance are not always so obvious and immediate. Permitting regulations in Texas started in 1987 and are implemented and enforced locally. Maintenance and reporting frequencies are included in the regulations, however, maintenance is responsibility of the homeowner. Inadequate design and poor maintenance can result in system failure and consequent discharge of sewage in the environment. This can cause contamination of sensitive sites, such as shellfish producing waters, lakes, and groundwater. Other local conditions can worsen the impact, as fine textured soil and/or shallow groundwater. Accurate knowledge of number and operation/performance efficiency and effectiveness of OSSFs is therefore needed. Current efforts to acquire that knowledge are though limited to the permitting data from Texas Commission on Environmental Quality (TCEQ), and to more detailed projects in specific watersheds. This has some limitations, including a fragmentation in the methodologies used, missing location of the systems, exclusion of old systems, double counting when a new permit is given to a system already permitted. A recent effort, funded by TCEQ, as a response to EPA requirements, addressed some counties along the coastal zone with the objective of building an OSSF inventory. The methodology created in the project would serve as the basis for the creation of an inventory for the entire coastal zone of Texas, and the final database as the starting point of a new method of continuous updating of new installed OSSFs. This would assist public officials in monitoring and enforcement of potential OSSF issues. Such new strategy is required from EPA and NOAA, under the Coastal Nonpoint Source Coastal Program. Furthermore, nowadays software and powerful hardware can easily handle such a large amount of data and the need for real time information. And the established network of permitting agencies has great potential to serve as effective structure to feed and update the database, verified that the work force is adequate. Texas A&M AgriLife is currently engaged in this process, and developed a new methodology to create an OSSF inventory. The method was successfully calibrated in three coastal counties (Chambers, Nueces, and Orange). Validation is underway in all the other coastal counties, and a plan has been made to create a new data entry method to allow continuous update and verification of the inventory as new OSSFs are installed or replaced. This paper will present features, challenges and results of the OSSF inventory methodology calibration process. Preliminary results of the validation in the other coastal counties will also be presented, including total estimated count and attributes of OSSFs in the coastal zone of Texas. A draft of the new data entry method will also be presented, featuring the database architecture and the planned involvement of permitting agencies. Current benefits identified in the process will be listed, as well as the expected impact on the environmental from failing OSSFs.

name of conference

  • 2017 Spokane, Washington July 16 - July 19, 2017

published proceedings

  • 2017 Spokane, Washington July 16 - July 19, 2017

author list (cited authors)

  • Bonaiti, G., Karimov, A., & JantraniaGerlich, A.

citation count

  • 0

complete list of authors

  • Bonaiti, Gabriele||Karimov, Askarali||JantraniaGerlich, AnishRyan

publication date

  • January 2017