Vacuum Sewers – Engineered Solution for a Multitude of Problems

The City of Albuquerque is celebrating its 300th anniversary in the 2006. The city itself has been growing at a very rapid rate, expanding the urban boundaries into the rural countryside. This urban expansion has been most apparent in the river valleys of the Rio Grande, where groundwater is shallow and topography is very flat. As the urbanization of the valley areas north and south of the City increased, the density of septic systems increased proportionally and began to affect the groundwater quality. This would eventually affect thousands of residents that individually and municipally relied on groundwater as a drinking water source. The New Mexico legislature challenged the City and County to “sewer the valley by 2000”, and eventually provided an initial 25 million in funding to begin the work. This was the beginning of a program which is only now nearing completion and will provide sewer service outside the City limits to thousands of additional residents.Due to the groundwater and flat terrain conditions in the North and South Valleys, alternative collection systems were considered in lieu of traditional gravity sewers. While gravity sewers were considered the first choice, vacuum sewers were chosen as the alternative of choice when gravity sewers were not viable. In total, nine vacuum systems are installed or are under construction, capable of serving over 8,000 residences. The use of vacuum sewers has solved many problems in the design and operation/maintenance of sewer systems in the North/South Valleys. Where streets in traditional housing developments have adequate room for subsurface utilities construction and maintenance, this is not the case in the valley developments. In many locations, only 15’ of width is provided for access and utilities including water, gas, electric, phone and CATV. The addition of a sewer within these existing utilities was a most problematic issue where deep gravity sewers would require removal/replacement of all utilities.