The Flood Control District is taking a watershed-wide approach to planning for this area. This approach provides a holistic view of activity in the watershed and enables the Flood Control District to deliver projects strategically and efficiently in a heavily developed area. Projects will include stormwater detention basins, channel improvements on Halls Bayou tributaries, and right of way acquisition for floodplain preservation.
The Halls Bayou Bond Implementation Program I is the watershed-wide effort working to implement the flood risk reduction projects identified in the 2018 Bond Program for Halls Bayou.
The projects identified in the 2018 Bond Program were originally identified in the 2013 Halls Ahead Study Vision Plan, which was developed with extensive community input between 2012 and 2013. The Vision Plan outlines an ambitious $1.75 billion plan for more than 20 miles of channel conveyance improvements and construction of stormwater detention basins to hold more than 10,000 acre-feet, or approximately 32.6 billion gallons, of stormwater.
In 2019, the Flood Control District completed an update of the 2013 Vision Plan and developed the Halls Bayou Phasing Study. The updated Vision Plan incorporated substantial updates enhanced modeling techniques, improved data collection (such as structure inventory, unit cost estimates, updated existing rights-of-way, flood claim data and other data), and insights gathered from ongoing stakeholder coordination.
The Phasing Study formulates a navigable pathway towards realizing the Vision Plan with smaller and more manageable project pieces. The phased approach for the Vision Plan will facilitate annual budget planning and securing of funds, early identification of potential funding partnerships, and will allow time for right-of-way acquisition.
The Phasing Study breaks the 58 flood risk reduction projects identified in the Vision Plan into 12 phases, with estimated costs between $100 million and $150 million per phase. Each project included in the recommended phases is designed to improve the level of protection from riverine flooding for structures, while also providing environmental benefits where possible. Each phase works together to provide benefits across Halls Bayou.
Projects may include channel conveyance improvements, construction of stormwater detention basins, and bridge modifications. Channel conveyance improvement projects could include: widening and/or deepening of channels, construction of grass-lined sections, retaining walls, concrete lining, enclosure with box culverts, and natural stable channel design. Projects designs will consider aesthetics, the need for right-of-way acquisition, environmental enhancement, recreational opportunities and budgetary constraints.