SCH Number 2017021050
- Rio Bravo Hydro Sediment Management Project
- The Olcese Water District (OWD) proposes to Rio Bravo Hydro Sediment Management Project (Project), which involves the implementation of measures to manage sediment accumulation at the Rio Bravo Hydroelectric Project (Rio Bravo), Federal Energy Regulatory Commission Project No. 4129. Sediment management methods include sediment pass through (sluicing) and mechanical sediment removal. Mechanical sediment removal involves suction dredging in the Rio Bravo impoundment every 1-5 years and the use of excavators to remove sediment from the Rio Bravo canal every 5-10 years. For each mechanical sediment removal event, OWD estimates that approx. 10,000-34,000 cubic yards of sediment could be removed from the impoundment and approx. 5,000-10,000 cubic yards of sediment could be removed from the canal. Sediment would be stored in designated disposal areas on Rio Bravo property. Sluicing through the Rio Bravo sluiceway is triggered by flow criteria, upstream sediment transport, and/or natural turbid flow conditions, and may occur multiple times each year. OWD designed sluicing triggers to maximize sediment mobility and limit impacts to biological resources. OWD estimates that approx. 1,000-1,500 cubic yards of sediment would be displaced downstream during each sluicing event.
3 documents in project