SU0014570 - Laserfiche WebLink

Home Browse Search

photo and on soils maps the streambed is riot evident on the ground. Ultimately Mosher Creek enters Disappointment Slough in the San Joaquin Delta about 7 miles to the west. Mosher Creek is leveed and according to Army Corps of Engineers the site has 100 year flood protection, although a standard project, flood, a flood much greater in extent and more unlikely, would flood the area south of Mosher Slough. According to the flood profiles in Plate 21 of the Corps of Engineers report. Streambed is at 30' msl datum at mile 9.0 (near the center of the site) and at 34' msl datum at the Central California Traction Company rail- road crossing. Mile 9.0 CCT Crossing Flow CFS. Streambed 30' 34' At Hwy 99 100 year flood 34' 38' 400 CFS Standard Project Flood 38' 41' 10000 CFS in addition to floodflows, the impervious soil and lack of slope cause minor drainage problems in the Morada area. Due to the lack of slope even slight topographic changes caused by road- building etc, can entrain water and subject areas to shallow ponding. 4, Subsurface Hydrology According to San Joaquin County Public works records, depth to water is about 70'-80' . The water table is' dropping at a rate of several feet per year. Furthermore the influx of saline water from the west due to groundwater overdraft and lack of surface water outflow have caused saltwater intrusion in the underground aquifers. If carried far enough this problem could eliminate pond water as a domestic water source. 5. Atmospheric Conditions (see Appendix B ) The Council of Governments "Noise Element" indi- cates that the California Traction Company rail- road line is a problem noise route. However, the traffic on this railroad is neither frequent nor high speed. -6-