Keeping Our Oceans Clean

Last week I got the opportunity to visit one of South Orange County Wastewater Authority treatment plants located in Laguna Niguel, CA.  I must say that I knew nothing about how wastewater was managed or treated, so the whole tour to me was very interesting and informative.  Plus, the tour was guided by a gentleman nameed Mr. Waters; how cool is that?
This one particular plant is a conventional activated sludge treatment facility with the capability of handing 12 MGD of liquid and an equivalent of 24.6 MGD of solid waste.  Mr. Waters walked us through the the basic processes of wastewater treatment.  The first step is the preliminary treatment, which involves removing debris, larger matter, and grit.  Next, the wastewater flows into the primary sedimentation tanks, where heavier matter settles and floatable matter rises to the top.  After the matter is separated, the wastewater is sent to aeration basins where the organic pollutants in the wastewater are broken down by microorganisms into carbon dioxide, water and energy.  The remaining microorganisms are then diverted to secondary sedimentation tanks and after sedimentation  the secondary effluent moves to the ocean outfalls. A portion of this secondary effluent goes through additional filtering (tertiary treatment)  to become "reclaimed" which can be used for irrigation and other industrial processes. All settled solids are pumped to heated digesters where they are
 broken down and converted into gas by-product of carbon dioxide, methane, and a more manageable solid matter.  The remaining solids are held in detention for a certain time, then they are dewatered and known as biosolids.  These biosolids are then shipped to a landfill or used as compost material.
Mr. Waters also, stressed SOCWA's commitment to stay on top of wastewater regulations and technology to ensure that the quality of our wastewater going to the ocean is environmentally sound. 
As I said above, the tour was very informative. You can find a detail chart of the processes on SOCWA's website http://www.socwa.com/Programs/Programs.aspx.