Comment Period Open For Draft 1, Version 1 of Open Data Standard for Recreational Water Quality

Swim Guide is developing a standard for exchanging recreational water quality data and we need your help.


  • Create a single standard for presenting recreational water quality data, so that different people monitoring different waters can share their results
  • Make the standard open, so that everyone can see it and shape it
  • Ensure data is shared in a machine-readable format (i.e., not pdf, not csv, not RSS) so that sharing is easy and automated
  • We need your help to refine the standard for the automated exchange of recreational water quality data.

    How to Contribute to the Open Data Standard for Recreational Water Quality Project

    Visit our open data standard project website :

    We encourage you to contribute to the standard draft on Github:


    Open Data Standard for Recreational Water Quality

    The purpose of recreational water quality monitoring is to protect public health from contaminated water. Even where water is tested, however, it can be very difficult for the public to get an answer to the question “is it safe to swim?”

    Hundreds of counties, municipalities, park organizations and nonprofits regularly test water for indicator bacteria, algae, and/or other harmful pollutants. The data should be shared quickly (within 24 hours) and with as wide an audience as possible in order to help people avoid waterborne illnesses; yet, this rarely happens.

    The public faces four common barriers when they try to understand the health of their beach or swimming hole:

  • Access. Much of the water quality information collected is never published. It lives in data silos that are not accessible to the public.

  • Ease of Access. Public water quality does exist, but it can often be hard to find. It may be buried on websites or phone hotlines that aren’t easy for people to locate.
  • Clarity. The data is presented in a way that is difficult for the general public to understand and usually differs from place to place.
  • Age. When data is shared, it is often very out of date. Many places, for example, still only publish annual or monthly testing results.
  • Lack of water quality information means that people – often unknowingly – swim in contaminated waters. Studies from the Environmental Protection Agency estimate the between 3%-8% of people experience acute gastrointestinal illness (AGI) after swimming. An estimated 3.5 million Americans get sick each year. In Canada, the number is approximately 400,000. Children are the most likely to get sick.

    Photo by Samuel Apuna

    The main reason water quality is not shared more widely is because there is no standardized way to present data.

    Since 2011, Swim Guide has spent thousand of hours each manually compiling water quality information from websites (some using legacy technologies), phone hotlines, and spreadsheets so that 1.5 million people can access beach water information. Meanwhile, regulators in different countries struggle to consolidate water quality results from different communities to inform policy and funding decisions.

    That’s why we decided to develop an open data exchange standard for recreational water quality information.

    An open data standard will increase data exchange, improve public awareness of water quality, and aid researchers trying to protect recreational waters. The initiative will reduce the number of people getting sick from contact with polluted water and increase the number of environmental protection plans for communities affected by pollution.

    This project is funded by the Canadian Internet Registration Authority (

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    Swim Guide divulgue les meilleures données que nous possédons au moment où vous voulez les consulter. Obéissez toujours aux avis affichés sur les plages ou diffusés par les organismes gouvernementaux. Restez vigilant et vérifiez s’il y a d’autres risques pour les baigneurs, comme les marées et les courants dangereux. Veuillez signaler les cas de pollution qui vous préoccupent pour que les affiliés puissent assurer la sécurité des personnes qui fréquentent les plages.

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