Data Quality Assurance

Quality is More Than a Name

Quality assurance (QA) is “the integrated program for assuring the reliability and quality of environmental data.” (from Ecology Executive Policy 1-21)

Why is Quality Assurance of Water Quality Data Important?

The caliber of water quality data is important for:

The quality of the data determines how useful and usable they are. As we clean up Washington’s waters Ecology strives to obtain the best data, at the lowest cost.

How do we support Quality Assurance of Water Quality Data in Washington State?

In 2004, Washington State enacted a law entitled the Water Quality Data Act. It relates to collecting and using water quality data. The law requires that the data used in certain water quality activities meet its credible data principles. The law further requires that Ecology develop a policy regarding the use and collection of water quality data. The three main goals of the policy are:

  1. to explain how data is used to inform decisions about water quality and water quality improvement projects,
  2. to describe criteria to establish data credibility, and
  3. to recommend appropriate training and experience for data collection.

Credible Data Policy (PDF)

Where can I find out more about Quality Assurance of Water Quality Data?

This website lists Ecology’s Water Quality Program (WQP) data policies and procedures. They help to improve the quality of the data used in Washington’s water quality improvement projects. Also presented here are the quality assurance methods that EAP employs. Organizations and individuals can use some of these documents if they wish to submit data to Ecology for consideration in water quality decisions.

Ecology's Environmental Assessment Program (EAP) has a tool to help citizens develop a Quality Assurance Project Plan (QAPP). Please click here to access the tool.

Policies, procedures, and guidelines associated with collection and use of water quality data

Links to QA Policies, Procedures, Guidelines | Related Information

The WQP encourages citizens to participate in gathering data to assess the quality of Washington’s waters. Occasionally, grants are available to help fund those efforts. Schools and educators also develop curriculum based on water sampling, testing, and data management. One example is the Chehalis Basin Education Consortium.


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Last updated February 2012