“Removing almost 100% of the pollutants from Wastewater makes us Nature's greatest ally.”
The Wastewater Division is one of five notable divisions at the Orangeburg Department of Public Utilities. The Wastewater Division provides quality wastewater collection and treatment to the customers at some of the lowest rates in the state.
The Wastewater Collection System
The City of Orangeburg has a wastewater collection system that dates back to as early as 1906. At that time it served an area of approximately 3 square miles.The service area since then has grown to approximately 22 square miles). The area includes a variety of users, primarily consisting of residential customers; however, commercial and industrial customers are also included. The system serves approximately 10,700 customers in all. The sewer system consists of gravity lines ranging from 4 inches to 42 inches in diameter and pressure force mains ranging from 4 inches to 16 inches in diameter. The force mains are fed by 19 pump stations in the outlying area.
Wastewater Biosolids Dryer
Prior to the installation of a biosolids dryer at the Orangeburg Wastewater Treatment Plant in 1997, the biosolids that remained after wastewater treatment were dewatered using a belt filter press to a solids content of 16-20%. The dewatered, aerobically digested material had the appearance and odor of moist topsoil, but the amount of water remaining diluted the nutrients in the dewatered cake. Approximately 7800 tons of this material was sent to the landfill each year. The dryer allowed concentration of nutrients through water removal as well as the destruction of potential pathogens. This thermal process produced a dried product well suited for land application, thereby allowing recycling while conserving valuable landfill space.
The treatment process begins with industrial customers whose discharges meet established regulatory requirements. These discharges, along with wastewater from domestic sources, are treated at the Wastewater Treatment Plant using a biological process. A majority of the biosolids remaining after treatment are the excess organisms that are produced during the treatment process, along with organic and inorganic material that cannot be further broken down during treatment. The standards for Use or Disposal of Sewage Sludge, 40 CFR Part 503, were signed into law and became effective in 1994. The purpose of these standards is to establish numerical, management, and operational standards for the use or disposal of biosolids that is applied to land or placed on a surface disposal site. Regulatory compliance at the industry level and the dedication of wastewater treatment personnel make possible the production of Class A “EQ” (exceptional quality) biosolids that are safe for use on a wide variety of crops.
Wastewater biosolids can be used as a natural soil amendment. They contain essential plant nutrients and organic matter, and are a beneficial soil conditioner. Around the world, applying biosolids to agricultural land for crop production has been a common practice for decades. They also can be used in forestry and landscaping applications.