Effluent sewer
Effluent sewers also currently serve fewer people than septic systems, which also use septic tanks, but simply dispose of the effluent by draining it into a leach field. About one quarter of United States homes dispose of their wastewater with septic tanks. However, effluent sewers are being looked at as a sewage treatment solution in areas where gravity sewer systems are not well-suited or when the high capital cost to build a gravity system is prohibitive. Areas that are less than ideal for gravity systems include areas that are large, but extremely flat and areas that require long-distance pumping, such as where homes are widely spread out or when several small villages or towns connect their sewage systems so that a centralized plant can be built.
Emerald Lake Hills, California
Emerald Hills used septic tanks until the early 1980s, a factor that limited building: In 1982, the year the sewer system was installed, the neighborhood had 900 homes. A building moratorium from the late 1970s to 1986 forestalled the boom—but by 1992, the count had boomed to 1,400, eliminating most of the vacant lots. Many of the new homes were large and expensive. Among the new residents were several Forty-Niners, including Joe Montana, as the team was then training in Redwood City. Today, only a few lots remain open, and though building of homes continues, most of them are on the sites of former cabins and vacation homes.