(i) Barrier notched on Sept. 28, 1991. Construction resumed on Oct. 10 and finished on Oct. 13. (ii) Barrier notched on Sept. 30, 1992. Construction resumed on Oct. 2 and finished on Oct. 9. (iii) Construction was delayed on 5/17 and resumed on 6/5 due to high flows. (iv) Barrier was breached on 5/ 16 on an emergency basis, but complete removal wasn't done until 9/3, after Corps demanded permit compliance of complete removal. (v) Barrier was installed in previous years. (vi) Installation delayed due to high flows. (vii) Not intalled due to high San Joaquin River flows. (viii) Not installed upon DFG's request. (ix) In 1963 and 1964 an old rock barge was intentionally flooded and sunk at the head of Old River in an experiment to see if it could serve as a temporary barrier. Results were not promising and rock was placed directly for the 1968 barrier. No barriers were in place in 1965, 1966 or 1967. (x) Flashboards adjusted to allow minimum 6-inches flow for fish passage. (xi) Spring Head of Old River not installed due to high flows in the San Joaquin River. (xii) Only above water portion of boat ramps constructed due to hgh flows. North abutment not installed until full closure of barrier. No "partial" barrier configuration for 2005. (xiii) Fall Head of Old River not installed because existing flows and dissolved oxygen levels in the San Joaquin River were sufficient for Chinook Salmon. (xiv) Not installed in accordance with Wanger decision to protect Delta Smelt. (xv) Non Physical "Bubble Barrier" installed as a pilot test to prevent salmon from entering Old River. (xvi) Includes installation of new culverts in the Middle River barrier north and south abutments. (xvii) The Non-Physical Barrier was planned but could not be installed due to high velocity currents in the San Joaquin River that posed excessively dangerous conditions for divers and ruled out the possibility of installing the necessary equipment on the channel bottom. (xviii) Started Grantline Canal barrier south abutment construction to replace culverts, using barge and crane from shoreline. (xix) Due to high flows the Grantline Canal barrier fish flashboard structure washed out and will be re-constructed at a later date. The weir section elevation had to be reduced to accommodate the high flow. All 6 culverts were in tidal position (closed). (xx) The Grantline Canal barrier weir section was completed back to it's designed weir elevation (1.0 ft NGVD) and all 6 culvert flap-gates were tied open. (xxi) The Grantline Canal flashboard structure was washed out earlier in the year and the California Department of Fish and Game did not require a notch this year due to high flows. (xxii) The 2013 spring Head of Old River Rock Barrier was not installed due to uncertainty about the benefits of installing the barrier to salmonid survival through the Delta. (xxiii) The weir was raised by one foot on June 22, 2016.