July 2015


Welcome to the annual event where volunteers contribute to our understanding of water quality in the world.

Volunteers have been submitting information during the annual Dip-In snapshot since 1994. Please join them in this international effort to track changes in water quality!

The Concept of the Dip-In is Simple

Individuals in volunteer monitoring programs take a transparency measurement on one day during the month of July. Individuals may be monitoring lakes, reservoirs, estuaries, rivers or streams. These transparency values are used to assess the transparency of volunteer-monitored waterbodies in the United States and Canada. When 5 or more years of data have been gathered on a site, it is used to determine trends. Over 2,000 waterbodies are now tracked for trends in transparency.

We accept data from any year. If you weren't able to enter your data from a previous Dip-In, you may still add that data. We also accept data from any date during the year. We welcome small programs to use our database as a data depository.

Secchi Dip-in Formally Added to the NALMS Roster of Programs

[March 10, 2015 - Madison, WI] – NALMS is proud to announce the addition of the Secchi Dip-in to its roster of programs. In April 2015 founder Dr. Robert Carlson agreed to transfer the Dip-in and its related copyrights, trademarks, and website to the care of NALMS. In turn NALMS agreed to fund the Dip-in and appoint a committee to manage the program.

The Secchi Dip-in enables volunteers to collect water clarity data in the USA and Canada. Dr. Robert Carlson started the Dip-In in 1994 and it has continued each year since. NALMS joined as a sponsor of the Dip-in shortly after it began and views this transfer as a natural extension of its long relationship with the Dip-in.

Most Dip-In volunteers use a Secchi disk to take water clarity readings. The program also welcomes those who use a turbidity tube or meter, or black disk. The color of water, bits of silt or clay, and algae can affect clarity. As such Dip-in data is a simple measure of some forms of pollution. And tracking changes in clarity can help us understand the use of land around a waterbody and may also point to the success of efforts to restore waterbodies.

NALMS is thrilled to organize the Dip-in as part of Lakes Appreciation Month this year during the month of July. Efforts are underway to update the Dip-in website (www.secchidipin.org) and NALMS will post details there and on its own website soon.


How To Participate

Click here for instructions to volunteers and program coordinators.

View Dip-In Data

Enter as a Guest and see how lakes in your area compare. Register to add or edit data.


The Secchi Dip-In is a Program of the North American Lake Management Society
© 2015 The North American Lake Management Society.