• With approximately 28,000 students and 5,000 faculty/staff members on the campus, OSU generates over 1.1 million gallons of wastewater each day.
  • Most interior drains on campus lead to the City of Corvallis wastewater treatment plant while most exterior drains lead directly to Oak Creek or the Willamette River without pre-treatment.
  • Interior and exterior drain disposal at OSU is regulated by the Federal Clean Water Act and the City of Corvallis Municipal Code.
  • Civil and Criminal penalties can be incurred from improper drain disposal!
  • No material qualifying as a hazardous waste may be disposed of in the drain.

Interior Drain Disposal Limits                       

The following criteria apply to liquid wastes disposed of through interior drains:

  • Liquids must have temperature of less than 150° F.
  • Liquids must be non-flammable, having a flash-point greater than 140° F.
  • Materials must not be viscous or solid which may clog plumbing.
  • pH of all discharged liquids must be between 6.0 – 9.5
  • Toxic, malodorous, or radioactive substances may not be drain disposed.
  • No petroleum oils, dyes, heavy metals, or organic solvents.

Exterior Drain Disposal Limits

The following criteria apply to liquid wastes disposed of through exterior drains:

  • Only clean rain runoff and de-chlorinated potable water may be disposed of in exterior drains.
  • No chemicals or other materials may be disposed of through exterior drains.

For questions regarding what can and cannot be disposed of down a drain, contact EH&S at 541-737-2273