Tag Archive for: crushed stone

The Land Trust’s stewardship team has been hard at work for the last few weeks finishing up a much-needed infrastructure project on the Vernal Pool Trail at Cathance River Nature Preserve! The Vernal Pool Trail connects Rensenbrink Dr to the Highland Trail near the CREA Ecology Center as it runs through forest, over ledge, and by some wetland areas. A long series of old rotten bog bridges were first removed with the help of two Bowdoin College student volunteer groups, then the surface was prepped for the construction of a 120 foot crushed stone pathway. A crushed stone pathway is preferable to bog bridging in this area primarily due to the longevity of the materials. Bog bridges in the soil type found at CRNP can be only expected to last 2-3 years, and the crushed stone pathway should last significantly longer.

The pathway required digging and smoothing of the muddy soil to create a stable surface to build on, then the laying out of a geotextile fabric to help hold the foundational layers together. Next, 6 to 12 inch rocks were carefully placed in a strong jigsaw pattern to hold the ever-shifting path as it lives through future seasons of freeze and thaw cycles. After several layers of this careful stonework (known as rip-rap), a few final layers of gravel were spread on top to fill in gaps and create a smooth walking surface.