Septic tank
While a properly maintained and located septic tank does not pose any more environmental problems than centralized municipal sewage treatment, certain problems can arise with septic tanks in unsuitable locations. Since septic systems require large drainfields, they are not suitable for densely built areas.
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.