Boston Harbor and Massachusetts Bay
MWRA Environmental Quality Department

Use the drop-down menu to view reports
required by MWRA's discharge permit.

Contingency Plan Exceedances

MWRA's NPDES discharge permit requires MWRA to report Contingency Plan exceedances to regulatory agencies and the public. The exceedances are triggered by unusual or unexpected results of effluent or ambient monitoring. Effluent monitoring takes place in the treatment plant, while ambient monitoring examines the environment surrounding the outfall.

Caution and Warning Level Exceedances

May 16, 2008
  Ambient Alexandrium (red tide)
Winter/Spring 2007
  Phaeocystis
Summer 2006
  Phaeocystis
Summer 2006
  Chlorophyll
August 21, 2006
  Effluent Menidia (inland silverside)
May 17, 2006
  Ambient Alexandrium (red tide)
Summer 2005
  Ambient Phaeocystis pouchetii (algae)
September 15, 2005
  Effluent Arbacia (sea urchin)
May 11, 2005
  Ambient Alexandrium (red tide)
April 2, 2004
  Effluent fecal coliform
Spring and Summer 2004
  Ambient Phaeocystis pouchetii (algae)
Summer 2003
  Ambient Phaeocystis pouchetii (algae)
Summer 2003
  Ambient mussel bioaccumulation
Summer 2002
  Ambient PAH and chlordane
May-August 2002
  Ambient Phaeocystis pouchetii (algae)
August 2002
  Effluent total suspended solids (monthly limit)
August 24, 2002
  Effluent total suspended solids
August 17, 2002
  Effluent total suspended solids
2001
  Ambient mussel bioaccumulation
December 18, 2001
  Effluent fecal coliform
April 2001
  Effluent toxicity
January 2001
  Effluent toxicity
December 14, 2000
  Effluent chlorine
December 7, 2000
  Effluent pH
Fall 2000
  Ambient chlorophyll
October 2000
  Ambient dissolved oxygen percent saturation


Many of our reports are in PDF format, which requires Adobe Acrobat Reader®, a free program available from Adobe Systems. To request a paper copy of any report, please contact the MWRA Environmental Quality Department at 617-788-4601, or e-mail us at web.enquad@mwra.state.ma.us.
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