Area Wide Optimization Program

2022 AWOP Award Recipients

2021 AWOP Annual Report

Since 1998, the United States Environmental Protection Agency has developed several new regulations to reduce the risk of biological contamination while limiting the risk from disinfecting chemicals and their byproducts.  The Area Wide Optimization Program (AWOP) was developed to help water systems meet successively more stringent regulations and achieve higher levels of water quality.

AWOP is a joint program between the EPA and states, and North Carolina has participated in AWOP since 2000. North Carolina works cooperatively with water systems to use existing equipment and treatment processes to improve or optimize water quality.

Initially, AWOP focused on comprehensive performance evaluations (CPE). Water systems that fail to meet turbidity performance criteria are required to perform a detailed review of treatment processes and practices. Several surface water systems in North Carolina have voluntarily participated in the CPE process in order to improve plant operations. Target turbidity levels are 0.1 NTU, well below the regulatory limit of 0.3 NTU. Water treatment plants that consistently achieve such a low level of turbidity achieve significant water quality benefits.

The next phase of AWOP is performance-based training (PBT). Performance-based testing joins water systems and state representatives together for hands-on training sessions. Small groups practice plant management and laboratory procedures, and learn ways to better use existing equipment. Performance-based testing sessions typically consists of five or six sessions where water system representatives study their own plants for homework assignments. The sessions focus on ways to use existing knowledge and equipment and challenge each person to improve some treatment process at his own plant. Participants in PBT sessions can expect to further develop investigative, reporting and presentation skills as well as become more familiar with other water treatment professionals in the area.

In order to meet both disinfection byproducts regulations and microbial removal requirements, many surface water plants must carefully control their multiple barrier treatment processes, including source water selection and protection, coagulation, sedimentation, filtration and disinfection as well as managing water age and consistency in the distribution system. Performance-based testing may also provide a valuable way for water plants to learn disinfection byproducts control techniques. By actively participating and by developing special studies, water plant representatives can learn how to control these compounds while still meeting microbial removal requirements.

The Ground Water Rule was published in late 2006. This regulation imposes new microbial removal requirements on some groundwater systems. The EPA is currently developing an AWOP pilot program to work with groundwater systems. North Carolina looks forward to the results of the pilot program and may adopt new techniques with groundwater systems.

Operators - What is AWOP? How can it help me?

Reference Guides

The reference guides below were developed by the North Carolina AWOP Program to provide useful technical information.


The spreadsheets listed below are used to optimize water treatment operations. Each spreadsheet provides tools for analyzing your system. The data returned by the spreadsheet may suggest how operations could be changed to improve performance. In order to use the spreadsheets you will need to enable macros.

  • Disinfection Byproducts Goals
    • The Disinfection Byproducts (DBP) Goals spreadsheet will help you assess historical DBP performance of a water system.
  • Jar Test
    • The Jar Test spreadsheet helps you to conduct jar tests that model coagulation and flocculation in your water plant. This helps you select the best settings for turbidity removal and organics removal.
  • Turbidity Optimization
    • The Turbidity Optimization spreadsheets (also referred to as OAS TurbOps) help you to analyze turbidity removal achieved by each stage of the water treatment process. This will demonstrate how different stages in the treatment process work together and may help you to identify opportunities for improvement.
    • 12 Filter OAS TurbOps
    • 36 Filter OAS TurbOps
  • Storage Tank
    • The Tank spreadsheet summarizes storage tank characteristics and assesses water storage tank turnover time and mixing. This will help you identify opportunities to decrease tank turnover time and to improve tank mixing.


The videos below provide additional guidance on how to find AWOP data and tools, as well as guidance on how to use them.

  • AWOP Page Navigation
    • This video provides guidance on how to best navigate the AWOP webpage, and describes what tools and data are available.
  • AWOP Data from IBEAM
    • This video shows how to obtain data from the North Carolina Public Water Supply Section's IBEAM data reporting website.
  • Jar Test Spreadsheet Introduction
    • This video gives an introduction to using the Jar Test Spreadsheet that is provided in the "Spreadsheets" section above.
  • Hydrant Sampler
    • This link takes you to an EPA page with a video that provides guidance on how to use a hydrant sampler to assess water quality in the distribution system.