Sites L and M Construction (2006)
Click on the image for a larger view.
 |
Diversion vault: A diversion vault was installed at each site to divert stormwater into the DIS. The existing stormwater beach outfalls were attached to the vaults to allow stormwater to bypass the systems during high intensity storm events. Stormwater flow measurements and sampling also took place within the vaults. |
 |
Installation of DIS distribution pipes: One storm pipe at each DIS site was diverted into a subsurface distribution pipe that was subsequently split to deliver stormwater into the two, independent banks of chambers at each system. |
 |
DIS chamber bank installation: Each DIS consisted of two independent banks of open-bottomed, HDPE chambers. A 1 ft layer of gravel was placed in the trench, then a nylon mesh was placed on top of the gravel and the chambers on top of the mesh. The chambers were secured to one another using screws and a 2 ft thick gravel layer was placed around the bank of chambers. A geotextile fabric was then wrapped around the sides and top of the chambers. |
 |
Monitoring well installation: Groundwater and water table monitoring wells were placed in the dune surrounding the DISs. The wells were made of PVC pipe and jetted into the dunes. The groundwater wells were used to collect groundwater samples and the water table wells were used to continously monitor the elevation of the water table. |
 |
Dune revegetation (2006): Installtion of the DISs required digging trenches with heavy equipment, resulting in the loss of natural vegetation, therefore, native dune plants were planted post-construction, during the growing season. |
 |
Site L, one year later (2007): Just over one year from installation, the vegetation at Sites L and M had returned to near the pre-construction state and continued to increase in density and diversity. |