Statewide Environmental Flows (SB3)

The 80th Texas Legislature (2007) established the Senate Bill 3 (SB3) process for environmental flows in order to determine environmental flow standards for all of the major river basins and bay systems in Texas.  Senate Bill 3 was designed to be an accelerated, stakeholder-driven, scientific and consensus-based process to establish environmental flow recommendations from which the Texas Commission on Environmental Quality (TCEQ) could set standards.  An important second output from the Senate Bill 3 process are work plans that describe additional data and detailed studies which are needed as part of the adaptive management component of the legislation to refine Senate Bill 3 recommendations and standards.

The intent of the Senate Bill 3 process is to address three major questions:

  1. How much water is needed to sustain a sound ecological environment in the state's rivers and estuaries?
  2. How can this water be protected?
  3. What is the appropriate balance between water needed to sustain a sound ecological environment and water needed for human or other uses?

Senate Bill 3 science teams are tasked with using the best available science to address the first question and are to consider only the environmental needs of their respective basins and bays.  The second and third questions are to be considered by SB3 stakeholder committees and by the TCEQ.  The process also involves a statewide Environmental Flows Advisory Group and a statewide Science Advisory Committee to oversee the basin-specific efforts.

To date, seven of 11 river basins have completed or are in the process of developing instream flow and freshwater inflow recommendations.  Because Senate Bill 3 was designed to be an accelerated process executed at the basin-level, the science teams for each basin have only one year to develop flow recommendations, and their corresponding stakeholder committees have only six months to develop their recommended flow standards.  Following completion of the science team and stakeholder recommendations, the TCEQ then has one year in which to develop and adopt instream flow and freshwater inflow standards for a basin.

Senate Bill 3 legislation divides the effort into 11 basins.  Priority basins, those containing an associated estuary, began the process according to the schedule below, and have either completed or are in the process of developing their first-round of environmental flow recommendations.