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FYI
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The combined authorized municipal and industrial discharge of wastewater — about
61.5 billion gallons per day — is enough to fill Texas Stadium home of the Dallas Cowboys 79 times over with wastewater every day.*
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Since the passage of the 1972 Clean Water Act, most water pollution control
efforts have focused on point-source pollution. Point-source pollution generally comes from the millions of gallons of wastewater discharged from
the pipes of industrial facilities and municipal sewage treatment plants into rivers, streams, lakes, and the ocean. Sources of wastewater may include
domestic wastewater inflow and infiltration—where storm water and groundwater get into the wastewater collection system—commercial
operations such as restaurants, food processing facilities such as canneries, agricultural operations, and industrial facilities.*
Wastewater is considered a potential source of pollution because it may—especially if it is untreated or only partially
treated—contain organic and inorganic materials that can be hazardous to both humans and other life forms. In many streams, treated wastewater may actually be cleaner than what is already contained in the stream; however, treated,
untreated, or partially treated wastewater may also contain small amounts of radiation or toxics that increase the
temperature of waters, affecting aquatic wildlife and habitat. Finally, discharged wastewater, especially if it is untreated
or partially treated, may lower the amount of dissolved oxygen in the receiving stream (oxygen is required by microorganisms that consume the organic material).
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FYI
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Wastewater flows from domestic sources average about 100 gallons per day for each
person served. During dry weather, however, highest flows are about twice the average flow, while minimum flows are only about half the average flow.
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Different organic materials in wastewaters require different
amounts of oxygen—commonly known as biochemical oxygen demand (BOD)—in order to break down and stabilize the material. The greater the BOD, the greater the oxygen-depleting effect of
the wastewater upon the receiving stream. The BOD of typical untreated domestic wastewater varies from 100 to 300 milligrams
per liter. Chicken blood from a food processing plant, on the other hand, might require from 1,000 to 4,000 milligrams per liter of BOD to treat.*
State Discharge Permits
As of September 2002, 2,401 municipal wastewater treatment facilities, both publicly and privately owned, were
operating with state wastewater discharge permits. Most of these—nearly 2,000—involved direct discharge into state
waters. In addition to these domestic treatment facilities, there were 841 industrial facilities with active state permits.*
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NUMBER OF STATE WASTEWATER PERMITS
FROM 1980 TO 2002
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Note: Does not include agricultural permits
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Source: TCEQ, Wastewater Permit Facilities Database
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About 18 percent of both industrial and domestic wastewater permits --- 568 in all -- are
no-discharge permits, which means that wastewater is stored, evaporated, or used for irrigation instead of being discharged into a river or stream. Finally, in 2002 there were 568 permits for
agricultural activities, primarily CAFOs—feedlots, poultry and dairy operations—that were required to obtain no-discharge permits from the TNRCC, meaning that the animal wastes cannot be
discharged directly into state waters, but are instead usually held in ponds.*
Since 1972 the amount of pollution discharged in wastewater by domestic facilities has decreased
more than 70 percent, while the amount of waste requiring treatment has increased by 85 percent.*
This improvement is due mainly to better technology and to requirements that wastewater in Texas be cleaned up to stricter standards.
Most discharges in Texas are concentrated near
major population centers like Dallas and Houston. The state processes about 200 new or revised industrial permits and about 500 new or revised municipal permits each year.* Since 1980, combined industrial and municipal permits have
increased from 2,907 to 3,242. While both the number of permitted municipal and industrial wastewater facility permits
have risen since 1980, during the past five years, the number of industrial permits has actually fallen due to consolidation of permits and to the economic slowdown..
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