Environmental flows describe the hydrological properties of water flows including the quality, quantity, timing, and amount necessary to maintain estuarine ecosystem functions (Montagna et al. 2013). Healthy estuarine systems carry out functions and processes that result in biomass. Proper water allocation upstream using different management strategies increases the chance an estuarine system will continue to function properly and benefit humans.
Management strategies geared at maintaining an estuarine system try to establish environmental flows for that system. The environmental flows proposed for an estuarine system can mimic natural flow patterns or use other parameters such as estimates of the minimum flows required by that system (TCEQ 2009).
Anthropogenic and climatic influences can alter the historic flows of streams and rivers. Dams, diversions, and droughts are examples of influences that may change the inflows received by an estuary. Creating environmental flow schedules and limits through management strategies help restore and conserve estuarine systems.