Full Public Notice Project Plans Attachment A Work Plan
PROJECT DESCRIPTION: During the construction of the proposed detention basins, the HCFCD proposes to discharge 1,210 cubic yards of clean fill material, 512 cubic yards of concrete, and 831 cubic yards of riprap into 1.17 acres (4,456 linear feet) into waters of the United States (US). This project will impact White Oak Bayou (E101-00-00), Vogel Creek (E121-00-00) other waters of the US, as described in the summary table of impacts in Attachment A.
The project activities include excavation of eleven stormwater detention basins (Basins A, B, C, D, E, F, G, H, I, J, and L). Basins A, C, D, E, H, I, and L are designed to be wet bottom basins and Basins B, F, G, and J are designed to be dry bottom basins. Construction activities would include excavation of all eleven basins, which includes deepening and widening of the existing HCFCD Unit #E121-02-00 stream channel within the footprint of Basin I, deepening and widening of an existing unnamed tributary to Vogel Creek (unnamed Ditch 1) within the footprint of Basin L, construction of two inflow structures along White Oak Bayou, and construction of two inflow structures and two outfall structures along Vogel Creek. The proposed project would create a total proposed flood volume storage of approximately 1,250 ac-ft.
The basins located west of Antoine Drive will connect to White Oak Bayou (Basins A, B, C, D, E, F, G) and are to be interconnected using culverts under existing roadways and the clubhouse parking lot. The interconnected basins on the north bank of White Oak Bayou (Basins A through E) will pull flow via two new inflow structures on Basin D. Within the project area, White Oak Bayou has a relatively low level of service, as the existing 10-year storm event is already out of banks at several cross sections and flow will spill into the basin from other locations during larger events. Basin F is an independent basin located south of White Oak Bayou. Basin G is a dry-shelf expansion on the south bank of White Oak Bayou meant to add floodplain volume directly to White Oak Bayou. While the primary purpose of the five interconnected cells (Basin A through E) will pull flow from White Oak Bayou, the basin will be partially be influenced by spillover from HCFCD Unit #E140-00-00.
The basins located east of Antoine Drive will connect to Vogel Creek and include three wet-bottom basins (Basins H, I, L) and one dry-shelf expansion (Basin J). Basins H and L are proposed to be interconnected, with flow entering the offline configured Basin H through a new inflow structure along Vogel Creek and flow exiting back to Vogel Creek through a new outfall structure on Basin L. Basin I will pull flow from Vogel Creek and HCFCD Unit #E121-02-00 through two new inflow structures and flow will exit to Vogel Creek through one new outfall structure.