Simmons Branch Drainage Improvement Project - Phase 2
- Storm Drainage System
- $5.6 million
- Stormwater Management (Lead)
Posted Monday, Nov. 6
The Stormwater Management Division has received approval to move forward with revised drainage improvements for both the Simmons Branch Phase II and the White Oak Lake project, which is a separate project that will follow approximately six months behind the construction of Simmons Branch. The reconstructed White Oak Lake will enhance the lake's normal pool, riser, emergency spillway, and top of dam elevations to reduce downstream flooding and meet infrastructure needs for the Simmons Branch Phase II project.
The revised project design for Simmons Branch Phase II includes options to either replace or rehabilitate the current 700-foot concrete box culvert, which is located in the center of the project. Other changes to the design include increasing the size of the Pineview Drive culverts and a private driveway bridge at 3605 Swift Drive to significantly reduce flooding to to homes that are upstream.
Residents were notified by mail about these most recent drainage improvement options in August. Completed design plans were submitted in October to the City's Development Services Department for final review and approval. Private utility relocation for the project is expected to occur in the fall and should take about three weeks to complete.
A mandatory pre-bid meeting was held on Oct. 11 to prepare for a projected construction bid date of Nov. 16. All environmental permits have been received and construction is expected to begin in January 2018.
Several homes are experiencing first floor and garage flooding in the proximity of Pineview Drive and along Swift Drive, which are upstream of Lail Court, in flood events smaller than a 10-year flood. In addition, the existing box culvert along Swift Drive is undersized and in need of repair. The purpose of this project is to reduce street flooding on Swift Drive, minimize structural flooding of homes, eliminate channel bank erosion, and lower project costs. The final project will at a minimum meet the 10-year level and in some areas provide up to a 100-year level of service.
Channel stabilization measures have been incorporated into the design to prevent bank erosion and loss of private property due to high velocities of Swift Creek.
|Fall 2013||Phase I completed|
|Winter 2017||Phase II public meeting held & 30% design plan developed|
|Summer 2017||70% design plan, private utility relocation, permit application, easement acquisition, and construction plans complete|
|Fall 2017||Project bid and award complete|
|Winter 2018||Project construction begins|
|Winter 2019||Project construction complete|
Simmons Branch Drainage Improvement Project - Phase II is the second portion of the City of Raleigh’s multi-phased project to reduce flooding along Swift Drive. A final phase will involve retrofit changes to White Oak Lake to further reduce peak flows and flooding experienced in the downstream Simmons Branch watershed.