Wastewater Department

New Chemical Room

The Chemical room that was part of the 2016 Wastewater Plant upgrade.

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Galloway Lift Station Panel Upgrade

Describe some quality or feature of the company. Write a short paragraph about it and choose an appropriate icon.

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Wastewater Current Events

Current Events at the Wastewater Treatment Plant

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School Tours Wastewater Plant

Council 4th Grade Students tour the Weiser Water Treatment Plant

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Welcome to the City of Weiser Wastewater Treatment Facility’s online presence!

Our operation consists of four major processes; Collection, Treatment, Biosolids Treatment and Laboratory. Our department is staffed 7-days per week with staff members on-call 24 hours a day. Staff members are Certified Wastewater and Collection Operators through the authority of the Idaho Bureau of Occupational Licensing. It is required that they maintain annual CEU’s to keep their licenses current. On-the-job training is offered for all employees and comprehensive records are kept of all activities at the facility. Our facility is located on west 9th Street in Weiser, Idaho.

Please call us at 208-414-1242

Collections Division

Our Collection division is responsible for cleaning and maintaining over 20 miles of underground pipeline, manholes, and three lift stations that carry waste from homes, businesses, and industrial facilities to our Treatment Facility. Operators make daily rounds to all Lift Stations to collect data and check equipment. A Vac-Con truck is used to help clean City sewer and storm drain lines. It can deliver pressure through specially designed nozzles is used for cleaning pipe walls and removal of debris. It then has the ability to suck the reject water up to be taken and disposed up properly at our drying beds at the WWTP. A closed circuit video recording system is used when necessary to create videos of the interior of pipelines. These videos are examined by qualified staff members to assess pipe condition and areas in need of repair or replacement.

Wastewater Treatment Facility

The Weiser Wastewater Treatment Facility operates under a NPDES permit provided by the US Environmental Protection Agency, in cooperation with the Idaho Department of Environmental Quality. The permit is periodically review, and renewed (usually every 4-years). The Treatment Facility receives raw sewage and waste from the entire city of Weiser, and one Industrial customer. Waste is initially screened as it enters the plant, and then goes through a grit removal auger to remove large solids and some inorganic materials. It then enters a series of Aeration Basins that are aerated by large industrial blowers and mixers to assist in the biological removal of waste. The water is called Activated Sludge because it contains a variety of microscopic organisms that aid in the consumption and degregration of the waste. Next it flows into Clarifiers, where it begins the process of settling out. Settled materials are then either wasted out or returned to the headworks for additional treatment. Clean water flows over the clarifier weirs and is then dosed with Sodium Hypochlorite to help disinfect the water before it is returned to the river for downstream users.

Wastewater Laboratory

The laboratory analyzes samples taken from all phases of the processes at the Wastewater Treatment Facility and from the Industrial User to ensure compliance with Local, State and Federal regulations. Results guide operators in making process adjustments to the Plant to obtain optimal control and the best Effluent quality as possible. In-house testing includes: TSS, VSS, BOD,COD, Cl2, Phosphorus, and Nitrates. Testing by an outside laboratory include: FOG, TAN and HgLow. Quality testing is done annually to verify our Compliance.

How It Works

The Weiser Wastewater Treatment Facility accelerates nature’s way of cleaning water and is Weiser’s choice to prevent water pollution. It is literally a controlled ecological system using both micro and macro-organisms.

It all starts at our homes and businesses:

Most of us don’t think much about what happens to our water after we brush our teeth, take a shower, or flush the toilet. From homes and businesses wastewater is transported through a network of underground pipes and mechanical lift-stations to the Wastewater Treatment Facility for treatment by multiple processes, removing pollutants before being discharged into receiving waters. (The Snake River)

The City of Weiser owns, operates and maintains more than 20 miles of sanitary sewer lines, three pumping (lift) stations, and one secondary Wastewater Treatment Plant.

STEP-1 Step Screen/Headworks

Wastewater entering the Treatment Plant passes through an automated Step Screen and waste-compaction system which removes debris larger than 1/2 inch from the wastewater stream.
STEP-2 Aeration Basins

Four rectangular tanks, each with a capacity of 225,000 gallons and equipped with fine air diffusers, provide an oxygen-rich mixing enviroment for billions of microscopic organisms which use the pollutants in the wastewater for food and also convert ammonia to nitrates, a prime component of fertilizer.
STEP-3 Secondary Clarifiers

Our clarifiers are two large circular basins holding 345,000 gallons each. Clarifiers separate organisms and solids from the water for a return trip back to the aeration basins in the form of “Return Activated Sludge” (RAS). Solids settle to the bottom of each clarifier tank and are pumped to “Sludge Digester” tanks for further treatment. (See”Bio-solids Treatment Process” below)

At this stage, over 95% of the pollutants have been removed.
STEP-4 Disinfection Contact Chambers

Two concrete tubes that are 6 feet in diameter and 300 feet long each hold 77,000 gallons of water. As water enters the Contact Chambers Chlorine Gas is added to destroy bacteria that survived the previous steps of the treatment process. Additional small particles settle out during this process, further cleaning the water.
STEP-5 River Discharge

After treatment and disinfection processes have all been completed, the clean water is released into the receiving waters of the Snake River (NPDES Permit, Outfall 001) which flows into the Columbia River and finally into the Pacific Ocean.

It all starts at our homes and businesses:

The City of Weiser owns, operates and maintains more than 20 miles of sanitary sewer lines, three pumping (lift) stations, and one secondary Wastewater Treatment Plant.

STEP-1 Step Screen/Headworks

Wastewater entering the Treatment Plant passes through an automated Step Screen and waste-compaction system which removes debris larger than 1/2 inch from the wastewater stream.
STEP-2 Aeration Basins

Four rectangular tanks, each with a capacity of 225,000 gallons and equipped with fine air diffusers, provide an oxygen-rich mixing enviroment for billions of microscopic organisms which use the pollutants in the wastewater for food and also convert ammonia to nitrates, a prime component of fertilizer.
STEP-3 Secondary Clarifiers

Our clarifiers are two large circular basins holding 345,000 gallons each. Clarifiers separate organisms and solids from the water for a return trip back to the aeration basins in the form of “Return Activated Sludge” (RAS). Solids settle to the bottom of each clarifier tank and are pumped to “Sludge Digester” tanks for further treatment. (See”Bio-solids Treatment Process” below)

At this stage, over 95% of the pollutants have been removed.
STEP-4 Disinfection Contact Chambers

Two concrete tubes that are 6 feet in diameter and 300 feet long each hold 77,000 gallons of water. As water enters the Contact Chambers Chlorine Gas is added to destroy bacteria that survived the previous steps of the treatment process. Additional small particles settle out during this process, further cleaning the water.
STEP-5 River Discharge

After treatment and disinfection processes have all been completed, the clean water is released into the receiving waters of the Snake River (NPDES Permit, Outfall 001) which flows into the Columbia River and finally into the Pacific Ocean.

Bio-Solids Treatment Process

STEP-1 D.A.F.T.

Solids which have settled to the bottom of the Clarifiers are pumped to the Dissolved Air Flotation Thickener (D.A.F.T.) tank where specially formulated polymers are added to to the mixture to separate floatable solids from the water. The water is returned back to the aeration basins for reprocessing and the solids are pumped to the aerobic digesters.
STEP-2 Aerobic Digesters

The wet solids (sludge) are pumped into Aerobic Digester #1 and mixed with air provided by fine air diffusers. Digester #1 has a capacity of 136,666 gallons. The organic components in the sludge continue to be digested by micro and macro organisms and as digestion continues the mixture is thickened. This process continues until digester #1 reaches capacity, about 42 days.

The contents of Digester #1 is then pumped into Digester #2 which has a capacity of 257,044 gallons. The aeration process continues, further thickening the sludge. After Digester #2 reaches capacity the sludge is pumped to our “Belt Press” process.
STEP-3 Roediger Belt Press

Thickened, digested sludge (wet solids) is pumped from our digesters to a Roediger Belt Press system. Specially formulated Polymers are added to the mixture to aid separation of water from the solids. This mixture is run over a series of rollers between two porous belts which squeezes over 85% of the water out of the solids and loaded into a dump truck using a conveyor belt. The sludge is hauled to the City’s “Drying Beds”.
STEP-4 Drying Beds

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Bio-Solids Treatment Process

STEP-1 D.A.F.T.

Solids which have settled to the bottom of the Clarifiers are pumped to the Dissolved Air Flotation Thickener (D.A.F.T.) tank where specially formulated polymers are added to to the mixture to separate floatable solids from the water. The water is returned back to the aeration basins for reprocessing and the solids are pumped to the aerobic digesters.
STEP-2 Aerobic Digesters

The wet solids (sludge) are pumped into Aerobic Digester #1 and mixed with air provided by fine air diffusers. Digester #1 has a capacity of 136,666 gallons. The organic components in the sludge continue to be digested by micro and macro organisms and as digestion continues the mixture is thickened. This process continues until digester #1 reaches capacity, about 42 days.

The contents of Digester #1 is then pumped into Digester #2 which has a capacity of 257,044 gallons. The aeration process continues, further thickening the sludge. After Digester #2 reaches capacity the sludge is pumped to our “Belt Press” process.
STEP-3 Roediger Belt Press

Thickened, digested sludge (wet solids) is pumped from our digesters to a Roediger Belt Press system. Specially formulated Polymers are added to the mixture to aid separation of water from the solids. This mixture is run over a series of rollers between two porous belts which squeezes over 85% of the water out of the solids and loaded into a dump truck using a conveyor belt. The sludge is hauled to the City’s “Drying Beds”.
STEP-4 Drying Beds

Describe the item or answer the question so that site visitors who are interested get more information. You can emphasize this text with bullets, italics or bold, and add links.