Project Name: Florida Power & Light Properties
Project Location: Pinellas County, FL
Permeable Aggregate Roads Offer High Environmental Benefits; With Low Environmental Impact.
Situated in the northeastern section of Pinellas County, the Brooker Creek Preserve spans 8,700 acres of wilderness. The preserve comprises forested wetlands and pine flatwoods, and is flanked by Pasco County to the north and Hillsborough County to the east.
Brooker Creek Preserve lies within the East Lake region of Pinellas County with Florida Power and Light transmission lines running directly through the center of the preserve. The construction of these transmission lines led to the creation of access roads, which obstructed the natural flow of the wetlands. After extensive research to identify the cause of the wetlands’ degradation, it was determined that the transmission roads were the culprit.
In 1998, HDR Engineering contacted R. H. Moore & Associates (Presto Geosystems’ material supplier) for guidance in selecting the appropriate product to construct a 13,000-square-foot access road. The goal was to facilitate the movement of heavy line trucks while allowing water to flow through the system to aid in the preservation and natural vegetation of the wetlands area.
The perforated GEOWEB® Load Support System was chosen to meet these conditions. The GEOWEB System is capable of providing load support without creating ruts and can facilitate the flow of water, even in situations where the entire road is submerged during the rainy season.
Geosynthetic Project Components:
- GEOWEB GW20V (mid-sized cell), 8-inch Depth
- Geotextile Separation Layer
Stream Crossing Project Results:
The GEOWEB System was installed on two Brooker Creek low-water crossing maintenance roads. With FDOT #57 stone (crushed limestone) infill, the system creates a stable mat to support Florida Power & Light’s line trucks over wet, soft soil areas. The GEOWEB 3D Confinement System creates a permeable pavement capable of supporting vehicular loads over non-load-supporting soils and functions as a stormwater retention system.
The first two crossings were completed in 2000 with great success. After the area was studied for five years and determined that the wetlands were rebounding, two additional crossings were then added in 2005.
Currently, all four crossings are still being used on a regular basis for maintenance of the transmission lines.
GEOWEB Low Water System Environmental Benefits
With Clean Aggregate Infill, the System:
- Confines granular infill, significantly improving load distribution.
- Reduces stormwater runoff, promoting groundwater replenishment.
- Functions as a natural stormwater retention system, allowing water to fill the aggregate voids and permeate into the existing ground.
- Cell wall perforations facilitate lateral cell‐to‐cell drainage beneath traffic areas, resulting in better performance in oversaturated soils.
- The stability of the pavement surface translates to a reduction in maintenance costs.
- Controls shearing and lateral movement of infill material.
- Supports the weight of vehicles and greatly reduces the compaction of underlying soils.
- Confinement provides additional structural strength allowing for a reduction in overall cross‐section
(50% or more).
Build Stable, Low Maintenance Access Roads Over Soft Soils
The GEOWEB® 3D system is a surface stabilization system that is fast to deploy, easy to install, and requires virtually no maintenance. Build access roads through environmentally sensitive areas or undeveloped land, while minimizing disturbance.