Senate Bill 3 emerged from the Texas Legislature in 2007 as an attempt to create certainty over how the state deals with allocating water to environmental flows. Senate Bill 3 created a process in the Water Code requiring regional stakeholder groups (referred to as Basin and Bay Area Stakeholder Committees or BBASCs) to develop consensus-based environmental flow standards and strategies to meet the environmental flow standards specific to the rivers and bay systems in a particular region. The concept of “environmental flows” describes the flows of water necessary to protect the ecological health of rivers and of the bays and estuaries that are the ultimate recipients of these flows. The consensus of the scientific community is that for environmental flow standards to be adequate to support a sound ecological environment in a stream system, they must include minimum subsistence flows, varying levels of base flows, high flow pulses, and overbank pulses that vary throughout the year. Environmental flow standards establish requirements that govern when a water right holder may remove water from a stream or a river (instream flow requirements), thus protecting that water for instream and bay or estuary environmental needs.
The Water Code directs the Texas Commission on Environmental Quality (TCEQ), after considering the stakeholder committees’ recommendations, to adopt environmental flow standards “adequate to support a sound ecological environment, to the maximum extent reasonable considering other public interests and other relevant factors.” This paper summarizes the environmental flow standard and strategy recommendations made by the six stakeholder committees that submitted reports to the TCEQ and compares these to the standards the TCEQ ultimately adopted. The adopted standards only apply to permits seeking a new appropriation of water or to an amendment to an existing water right that increases the amount of water authorized to be stored, taken, or diverted.