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Mr. Roush explained that the City conm~its to adequate disposal capacity that meets the demands of this project. Mr. Tarver asked if staff was certain there is capacity for this project. He did not want difficulties with the Livermore-Amador Valley Wastewater Management Agency. Mr. Roush stated that Dublin San Ramon Services District had indicated there would be capacity. Ms. Dennis referred to Condition 4/59 regarding additional flooding protection to protect houses on the western parcel and inquired why 59b was lined out. Mr. Swift said that since the conditions were first drafted two to three years ago for the San Francisco project, staff had reviewed the area with engineers. If there are no flood improvements made and if it were possible to have a flow of 25,500 cfs to reach this site (which it won't) there would be flooding on the San Francisco side of the channel. The old FEMA map indicates that a 500 year flood would occur across the San Francisco property but not onto the western parcel, with the exception of a very small area of Golden Eagle Farm on the eastern side where single family houses are located closest to the creek. The intention several years ago was that if a portion of the San Francisco Bernal property were either raised by fill or protected by a berm from that kind of 500 year flood, that potentially flow could be shifted onto the western side and increase the flooding in that particular area, which have pad elevations lower than the top ofbank on the other side ofthe Arroyo. Inthe existing situation, ifthat kind offlood ever arrived at that portion of the creek, which it can't do today, those portions of the Golden Eagle lots would get their driveways wet belbre water would spill onto the San Francisco property. With the set back proposed in the Greenbriar plan and the raising of the pads above that 25,500 cfs flow, adding fill doesn't change the situation of those ft:w Golden Eagle houses at all. They would still get wet before water gets out of bank onto the San Francisco property and the amount nfflood plain taken out of the basin in this area is so tiny, it would impact the flood basin of the channel by millimeters. With that information, staff deleted that section because it leads to questions that anything could be done on the property without having impact on the Golden Eagle properties. Staff is satisfied that the kind of flood protection proposed is absolutely appropriate. The last thing the City should be trying to doing in this area is to allow houses to be built in a location that would pnt them at risk. So the requirement fbr raising the pads protects them from the 100 year flood as measured by Zone 7 and the 500 year flood as measured by FEMjt under the existing charmel configmration. If improvements are made upstream or downstream, Greenbriar's houses would be the last houses to flood in Pleasanton. The houses on the west bank would be in the 500 year flood plan whether there is development by Greenbriar or not. Ms. Dennis asked if the water will flow more easily when the old bridge abutment is removed and if there is any liability from impacts downstream? Pleasanton City Council 17 08/21/00 Minmes