Pismo Beach Wastewater Treatment Plant - Pismo Beach, California USA
Posted by: Groundspeak Premium Member teeoff2
N 35° 08.418 W 120° 38.026
10S E 715574 N 3891165
Quick Description: Pismo Beach California Waste treatment plant.
Location: California, United States
Date Posted: 12/8/2007 10:36:06 PM
Waymark Code: WM2QQ1
Published By: Groundspeak Regular Member Rupert2
Views: 96

Long Description:
This is a newly built waste treatment facility. It should provide service for many years to come
What is the capacity of the facility?: Average Flow 1.6 mgd, Peak 6 mgd

Describe the biological treatment technology used.:
Now, a single mechanical bar screen with a 0.625-in. (16-mm) bar spacing and a 6-mgd (23,000-m3/d) capacity captures large debris, such as rags and sticks, from the raw wastewater in the headworks. From the headworks, an influent splitter box divides the flow between two oxidation ditches, each with a side water depth of 12 ft (3.7 m) and a volume of 0.89 million gal (3.4 million L). Aeration is provided by mechanical aerators; about 12% (0.11 million gal [0.42 million L]) of each tank is anoxic, and 88% is aerobic (0.78 million gal [3.0 million L]).

Biological nutrient removal is utilized through the plant’s oxidation ditches. This process promotes removal of nitrogen from the wastewater without chemical treatment. Future wastewater reuse is achievable with this type of treatment, should the city ever decide to pursue it.

Effluent from the oxidation ditches passes through the mixed liquor splitter box to be evenly distributed between the plant’s two 65-ft-diameter (20-m-diameter) secondary clarifiers. These clarifiers each have a side water depth of 14 ft (4.3 m) and a volume of 0.35 million gal (1.3 million L).

From the secondary clarifier, the flow travels through a sodium hypochlorite mixing box to the chlorine contact basin. An adequate detention time and environment is provided in this basin to disinfect the water. To neutralize the toxic effects of the chlorine, the effluent is dechlorinated with sodium bisulfite. The disinfected and dechlorinated effluent is discharged 1 mi (1.6 km) off the coast of the Pacific Ocean under about 60 ft (18 m) of water.


How are biosolids (sludge) managed?: Dewatered biosolids are hauled to a composting facility.

What technology is used for disinfection prior to dicharge of treated water?: Cholrination

Who is the owner/operator fo the facility?: Pismo Beach

What is the website of the WWTP?: [Web Link]

How is the facility governed?: Not listed

Visit Instructions:
Please post at least 2 original photographs of the site. We would much rather see photos of the plant itself as opposed to the front office, but we also understand that security and site layout may limit your opportunities.
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Papou visited Pismo Beach Wastewater Treatment Plant - Pismo Beach, California USA 10/27/2013 Papou visited it
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