Environmental flows: The savannah process

Because The Nature Conservancy's approach to site-specific environmental flow assessment and implementation was first described for the Savannah River in Georgia, USA, it has acquired the nickname "the Savannah Process." Like the DRIFT method and the Building Block Methodology (BBM), the Savannah Process addresses the linkages between diverse flow characteristics and ecosystem components. This holistic method relies on facilitated expert consensus to prescribe environmental flows. The process consists of five steps. Step 1 is a one-day orientation meeting to inform and engage interested scientists, water managers, government agencies, and other stakeholders and provide a forum to express their values and concerns for the river. Step 2 is the preparation of a literature review and summary report describing existing data and knowledge of the river-floodplain-estuary system, species, and their flow dependencies to describe the annual and inter-annual flow or inundation patterns needed to support ecosystem health. Step 3 is a facilitated expert workshop, typically about two days, with participants representing expertise in all riverine ecosystem components. During this step, scientists are tasked with developing a set of environmental flow components (EFCs), which can be discussed by workshop participants in breakout groups. The whole group then reconvenes for a final review and agreement upon a unified environmental flow prescription. Step 4 is the initial implementation of the flow prescription. Following the flow workshop, scientists continue a dialogue with water managers to identify opportunities for implementing portions of the recommendations. Step 5 consists of additional data collection and research as needed to refine the environmental flow prescription. To date, the Savannah Process has been applied in a range of contexts around the world, mostly to guide changes in existing reservoir operations.