Animation 1: San Joaquin River

Animations #1, #2, and #3 compare the flowpaths of water originating from the Sacramento River for 3 dates under a range of hydrological conditions (see details in boxes at upper left). The dates and times are indicated at the lower left. The flow differences among the Sacramento and San Joaquin Rivers and associated tributaries, combined with tidal oscillations, move the Sacramento River water downstream into the San Joaquin River and Delta. Based on the model calculations, blue particles are inserted continuously at the location of the Sacramento WWTP on the Sacramento River (off-screen), starting at the beginning of each of the 15-day model calculations.

Animation #1 shows the model output for July 1-15 2009, for flows in the Sacramento and San Joaquin Rivers of ~18,500 cfs and ~850 cfs, respectively, when the Delta Cross Channel (DCC) is open.

Animation 2: San Joaquin River

Animation #2 shows the model output for October 1-15 2009, for flows in the Sacramento and San Joaquin Rivers of ~9600 cfs and ~1200 cfs, respectively, when the Delta Cross Channel (DCC) is open.

Animation 3: San Joaquin River

Animation #3 shows the model output for January 1-15 2010, for flows in the Sacramento and San Joaquin Rivers of ~11,000 cfs and ~4800 cfs, respectively, when the Delta Cross Channel (DCC) is closed.

Animation 4: Sacramento River

Animations #4, #5, and #6 introduce additional information to the simulations shown in animations #1-3 by using different colored particles to compare the flowpaths and mixing of waters originating from the Sacramento River and other locations in March 2009. For all 3 animations, flows in the Sacramento and San Joaquin Rivers are ~12,300 cfs and ~1200 cfs, respectively, and the Delta Cross Channel (DCC) is closed (see details in boxes at upper left). The dates and times are indicated at the lower left.

Animation #4 illustrates the paths and mixing of waters originating from two sources: (1) the Sacramento River (blue), and (2) the Lisbon Toe Drain (pink), a slough that drains into the Cache/Yolo Slough Complex. Particles are inserted continuously at each location starting March 18th at the start of the model calculations. The Lisbon particle insertion rate is one-fifth the level of Sacramento insertion rate, but particle density is NOT an indication of relative volume contributions. The animation shows that at these low Lisbon Toe Drain flow rates, these waters essentially remain within Liberty Island. Sacramento waters follow several paths downstream, mixing with waters in the south end of Liberty Island and also spending time mixing with waters in Cache Slough due to tidal actions.

Animation 5: Sacramento River

Animation #5 illustrates the complex mixing of waters near the confluence of the Sacramento and San Joaquin Rivers at RM0. The pink particles in the mainstem Sacramento River and the blue particles on the downstream end of the confluence of Georgiana Slough and the Mokelumne River represent slugs of Sacramento River water that reach the indicated locations on March 19th at 18:00. The cyan particles represent San Joaquin River waters. Under these hydrodynamic conditions in the Delta, Sacramento River waters are seen to spend a significant amount of time traveling through Threemile Slough, the lower San Joaquin River, and through the confluence. Only a small proportion of the particles that had traveled down Georgiana Slough (blue) mix with mainstem Sacramento River waters (pink), and practically no San Joaquin River waters (cyan) penetrate into the downstream end of the San Joaquin River and out to Suisun Bay.

Animation 6: Sacramento River

Animation #6 introduces additional information to the Animation 1 particle simulation, where blue particles indicate Sacramento River and pink particles indicate Lisbon Drain water. To illustrate the paths and mixing that Sacramento River waters take into the east Delta and the San Joaquin River, the insertion of cyan blue particles begins at 21:30 on March 18th when Sacramento waters first reach Georgiana Slough. To illustrate the range of mixing of the waters originating in the Sacramento River in Cache Slough and Liberty Island and downstream back into the Sacramento River, the insertion of green particles in Cache Slough begins at 12:45 on March 19th when the blue Sacramento particles first reach that location.