LSSC participated for the first time in the Bay Area Science Festival at the East Bay Discovery Day event held at Cal State East Bay on Saturday, October 26. Our exhibits included a debut of the improved percolation column experiment, which has larger and longer tubes and valves that are much easier to use, especially for younger children. Also new in this exhibit was the demonstration that a mixture of sand and rocks drains slower than either sand or rocks by themselves. The sand fills only the space between the impermeable rocks, so there is less sand volume to transmit the water. These experiments relate to understanding groundwater storage and recharge for our water supply.