Nước mặn xâm nhập trong các tầng nước ngầm ven biển của Los Angeles County, California Ven biển miền Trung và Tây lưu vực nước ngầm (CWCB) là hai hệ thống tầng nước ngầm ven biển nằm tiếp giáp với Thái Bình Dương ở phía tây nam Los Angeles County, California (Hình 1). Nước ngầm nghiêm trọng thấu chi của các lưu vực từ đầu những năm 1900 đến cuối những năm 1950 gây ra mực nước giảm xuống dưới mực nước biển, cho phép nước mặn xâm nhập vào các tầng ngậm nước uống, gõ giếng ven biển của dịch. | CHAPTER 2 Saltwater Intrusion in the Coastal Aquifers of Los Angeles County California . Johnson R. Whitaker 1. INTRODUCTION The Central and West Coast groundwater basins CWCB are two coastal aquifer systems located adjacent to the Pacific Ocean in southwestern Los Angeles County California Figure 1 . Severe groundwater overdraft of these basins from the early 1900s to the late 1950s caused water levels to drop below sea level allowing saltwater to intrude into the potable aquifers knocking coastal wells out of service and threatening the usability of this major water supply reservoir. In an effort to halt the intrusion and control the overdraft groundwater management agencies took three major steps from the mid-1950s to mid-1960s including 1 construction of freshwater injection wells along the coast to prevent the saltwater intrusion by the Los Angeles County Flood Control District LACFCD 2 seeking adjudication of the groundwater basins to limit the amount of groundwater that could be pumped annually and 3 creation of the Water Replenishment District of Southern California WRD to purchase artificial replenishment water to make up the annual and accumulated overdrafts purchase barrier injection water and to protect the water quality of the CWCB. This chapter will describe the current saltwater barrier system in the CWCB the monitoring modeling and management efforts underway to prevent continued intrusion and present the results of an investigation to identify cost-effective alternatives to injection wells for saltwater intrusion control. Copies of several reports that provide additional information about the groundwater basins and the barrier alternative study are available on the accompanying CD. 2004 by CRC Press LLC Figure 1 Study area and location of saltwater barrier projects. Project Area The coastal plain of Los Angeles County contains four groundwater basins including the Central Basin the Hollywood Basin the Santa Monica Basin and the West Coast .
