Our water group, Petenwell and Castle Rock Stewards (PACRS) is excited to tell you about the use of “Socks on Docks” to assist in removing phosphorus and nitrogen (nutrients that cause algae blooms) from our lakes.  This letter is meant to be informative about these biochar socks and how PACRS are going to study their effectiveness in taking nutrients out of Petenwell and Castle Rock lakes.

Socks on Docks are sacks filled with biochar, which is wood that has been burnt, somewhat like charcoal. When placed into the water it absorbs the nutrients (nitrogen and phosphorus) which is the fuel for algae growth in our lakes. These bags hang off piers, without touching the lake bottom, for the summer season and are removed in the fall. They last for 2-3 years. At that time the biochar sock contents can be put into the ground to release the nutrients and carbon back into the earth. The bags cost around $25.00 each.

PACRS is cautiously optimistic about how these biochar socks could supplement other conservation actions that we support from farmers and homeowners around the lakes.  We are going to support testing on their effectiveness in the Southview Shores HOA this year with guidance from the DNR.  Some members in PACRS are ready to purchase them for their docks ahead of the test results. 14 Mile Water Association (includes the Tri-Lakes) members will be implementing this on their lakes this year as well. 

Presently, we cannot estimate the impact these socks would have on large bodies of water like Petenwell and Castle Rock Lakes.  PACRS just wanted to inform you that we are gathering information and support testing this year.  If you or your HOA would like to purchase Biochar socks to try at your dock, feel free to contact PACRS. https://bit.ly/socksondocks 

We will place a larger order with others to reduce impact of freight on the costs to our area. We feel confident that Socks on Docks can help to pull nutrients out of our lakes and possibly decrease algae blooms but currently can only provide antidotal evidence. 

Please consider trying them on your dock. You may also consider becoming a member of PACRS. https://pacrs.org/get-involved