POSH Module Build – Living Shoreline for Riverview Park | Saturday, May 2

Help us build Pervious Oyster Shell Habitat (POSH) Modules – 30-pound balls of recycled oyster shells and cement that form the foundation of a natural oyster reef along the Trout River.

A single adult oyster can filter up to 50 gallons of water per day, and as a reef grows, it creates habitat for hundreds of aquatic species while acting as a natural buffer against coastal erosion and storm surges.

Over 85% of natural oyster reefs have been lost worldwide. Every module we build helps turn that tide.

In August 2025, volunteers installed 40 POSH Modules at Riverview Park, creating approximately 140 feet of oyster reef. Now we’re growing it further.

No experience needed — just a willingness to get a little messy and a lot of heart for the river.

Volunteer Shift 1: 8-11 a.m. at 2000 Ponte Vedra Blvd (parking lot by Guana Reserve Middle Beach)

Morning shift volunteers will load 13.5 trash cans of recycled oyster shells and bring them to the GTM Research Reserve Welcome Center (505 Guana River Rd, Ponte Vedra Beach, FL 32082). It will likely take 2-3 trips. Loading the shells wont take up the entire shift, so once complete volunteers will be able to start on the POSH Module molds.

Volunteer Shift 2: 11 a.m. – 2 p.m. at GTM Research Reserve Welcome Center

Afternoon shift volunteers will come straight to the GTM Research Reserve Welcome Center (505 Guana River Rd) to relieve the morning shift volunteers. You’ll get straight to work on creating the POSH Modules. The process involves mixing oyster shells, cement, and water into a cement mixer where shells will get an even coat of cement. They will then be poured into hexagonal molds.

Register here to participate in either shift.

The POSH Modules will be stored for about a month to cure. Then they will be removed from the molds and deployed into the river to help create oyster habitat!

Nature-based Solutions: Improving Water Quality One Oyster at a Time