Bullhead Slough Rehabilitation

Scope of Work

Bullhead Slough (“Slough”) is a manmade channel that serves as an inline detention/amenity basin. The slough consists of three segments. All three segments are bounded on the north and south by Victoria Gardens Drive and Old Dixie Drive, respectively. The first segment, Eastern Pond 3, begins at Colonel Court Drive and ends at Old South Road. The second segment, Middle Pond 2, begins at Old South Road and ends at Farmer Road. The third segment, Western Pond 1, begins at Farmer Road and ends at the outfall into Oyster Creek. This project includes the first and second segments, or Eastern Pond 3 and Middle Pond 2. The third segment, Western Pond 1, will be rehabilitated under a different project in the future.

Existing Conditions

Over time the Slough’s side slopes have eroded. The diminished side slopes reduce the slope’s stability and can lead to worsening slope failures. Additionally, silt, or very fine dirt, has been deposited along the entirety of the Slough as a result of slope erosion and run-off. Silt has built up and reduced the depth of the Slough and created islands of vegetation growth. The shallower water leads to mosquitos, algae, and vegetation as well as reduces detention volume. Finally, the build-up of silt disrupts the fountains within the Slough.

Proposed Conditions

This project will resolve both of the existing condition issues of failed side slopes and silt build-up by removing the silt by dredging and restoring the side slopes with ShoreSOX installation. The dredged material is pumped into a dewatering bag to dry and then is hauled off-site and legally deposited. ShoreSOX re-stabilize shorelines using an open-ended containment system that is filled with locally sourced organic material. The ShoreSOX are then seeded to allow vegetation to grow through the sock and halt soil erosion.

Schedule

The Notice to Proceed will be issued on July 6, 2020 and the project is expected to be completed in November 2020.

Procedure

The Contractor, Storm Water Solutions, will begin by prepping the ShoreSOX along the edges of the most eroded side slopes. They will stage the primary dewatering bags on the northeast side of the Eastern Pond 3. They will also stage auxiliary/backup dewatering bags near the southwest side of Western Pond 1. The Contractor will then use a crane to place the hydraulic dredge into Eastern Pond 3. The dredge will remove silt via pumping into the dewatering bags. The dewatering bags will be surrounded by haybales as stormwater pollution prevention and to prevent any silt from reentering the slough. The dewatered material will be tested for acceptability for filling the ShoreSOX in lieu of imported soil/mulch. If unsuitable, the dewatered materials will be loaded into trailers and hauled off-site for legal disposal. This process will be repeated for Middle Pond 2.

The Contractor is allowed to work from 7 a.m. until sunset for seven days a week. At this time, the Contractor does not expect to work seven days a week in order to achieve the project delivery schedule. Weekend schedules will be approved on an as needed basis.

Residents are reminded that this is an active construction site. DO NOT enter construction site at any time.