1925 to 1930: Construction Begins

The original portion Weiser’s collection system (sewer pipes and main lines) was constructed using terra-cotta clay pipe. The pipe joints used no grouting at all to allow for ground water infiltration, creating a “combined” sewer system which discharged directly into the Snake River and Monroe Creek. The theory behind this practice was the widely held belief that “dilution is the solution to pollution”.

Federal work projects during the depression years brought additional sewer work to Weiser. Excavation was performed using manual labor, with trenches as deep as 25 feet. Deep line construction was a common practice since pumps at the time were unreliable.

1959 – 1960: Primary Treatment Facility

The “”primary” wastewater plant and three “pump stations” (Main, Commercial and Galloway) were constructed along with cement and asbestos-concrete sewer lines north of Galloway street and west of West 9th street. Raw sewage was now treated by being pumped to the Wastewater Plant via the lift stations and treated before being discharged into the Snake River.

Weiser’s northwest area sewage flowed through a main line on west 6th street and the east side of town was pumped from the Commercial street lift station to to the Main Lift station where it was pumped to the new facility on west 9th street.

1972: Federal Clean Water Act Passed

1987: Secondary Treatment Added

The Weiser Wastewater Treatment Facility was upgraded to include secondary treatment of wastewater using an “activated sludge” process to meet the growing needs of our community and comply with stricter water quality standards. The wastewater treatment facility was now capable of a hydraulic average capacity of 2.4 million gallons per day and a peak capacity of 3.75 million gallons average daily flow, enough  to cover an acre of ground with 18 feet of water.

1989: Jetter Purchase

The City of Weiser purchased a Camel Jet pressure washer system (The Jetter) for cleaning sanitary sewer, storm lines, manholes, and catch basins. This unit was also capable of drilling holes in the ground using a high-pressure water stream and special attachment. A Jetter was purchased so that City crews could clean the City’s sewer lines to prevent clogging and deterioration of infrastructure, as well as readily respond to citizens concerns of odors or plugged lines. It enabled city crews to maintain the towns collection system verses hiring outside contractors.

1989: Under Drain/Sewer Lines

Installation of a groundwater under-drain pipeline and rehabilitation of sewer lines on the east side of Weiser. Clay pipelines were replaced with PVC pipe through a grant from the Economic Development Authority and the assistance of Holladay Engineering.

1992: Infrastructure Utility Maps

Holladay Engineering prepared utility maps showing locations of sewer, water, and storm drain lines. A manhole numbering system was also developed.

1994: Fine Air Diffusers

Replacement of Coarse air diffusers with fine air diffusers to improve oxygen saturation levels in Aeration Basins and Digesters. This improvement provided better treatment of the secondary processes, while also increasing equipment efficiency and energy cost savings.

1995 & 1998: Sewer Line Rehabilitation

Rehabilitation of aging sewer pipe throughout Weiser to reduce inflow and infiltration of ground and surface water.

1997: Belt Press & Drying Beds

A belt Press was installed at the Weiser Wastewater Treatment Facility to remove water from digested solids. Drying Beds were constructed above the Washington County Transfer Station. With these improvements the Weiser Wastewater Treatment Facility became one of the few plants in the area capable of producing “Class A Bio-solids” for dry application to farm ground. Prior to these upgrades, all digested solids had to be hauled with a tanker truck and applied wet, then tilled into the soil.

2001: Vactron Purchase

The City of Weiser purchased a Mobile Vactron unit to accent the Jetter truck. Collection operators were able to jet lines over the years, but that just pushed solids down the collection and storm lines. The Vactron could vacuum the solids out of the sanitary, storm and catch basin systems.

2002: Digester Rehabilitation

The digesters were converted from anarobic, to aerobic digesters for improved safety, operational efficiency and better bio-solids

2014: Vac-Con Purchase and Map Upgrades

The City of Weiser purchased a 2008 Vac-Con Sewer All-in-One unit. This unit provided the flexibility to both jet, and suck debris with one unit. It also allowed us to reach deeper and further than the previous unit(s).

Using GPS locating and mapping. The City hired an engineering firm to help update our mapping system for more accuracy and digital access.

2016: Wastewater Plant Upgrade

Due to the new regulation set forth by the Regulatory agencies regarding the removal of phosphorus from rivers and steams, the City of Weiser was positioned to upgrade the plant in order to meet the new stringent guidlines. With the help of USDA and the Idaho DEQ, the City was able to secure funding for the project with available grants/loans. Following are the things that were upgraded:

• Added a Grit Removal system
• Enlarged the Influent building and added a new Step Screen and hazardous gas monitoring systems
• Reconfigured the (4) existing Aeration Basins so the could serpentine instead of just run parallel.
• Added (2) mixers to Aeration Basin #1, and removed the old diffuser air system to make it an Anarobic / Anoxic Zone.
• Upgraded the remaining (3) Basins with new Diffused Air piping and diffusers.
• Fitted Basin #4 with a mixer and recirculation pump.
• Installed (2) new Aerzen Blowers and communication systems
• Built a new building and Installed a new On-site Sodium Hypochlorite system with (2) large storage tanks and (3) Watson-Marlow pumps.
• Added (2) large Aluminum Sulfate tanks with (2) Watson-Marlow pumps for Phosphorus chemical control.
• All (3) Digesters had upgraded piping and new diffusers.
• A new skid Polymer Injection system was installed for the DAFT.
• Numerous old valves around the plant were decommissioned and replaced with new valves, some pneumatic.
• Numerous old motors were pulled and replaced with new energy efficient models.
• All entire Wastewater Plant received a fresh coat of paint.
• The main office, Effluent and Blower buildings all received new roofs.
• New locks were installed on all the doors.
• New SCADA Controls and systems were installed throughout the plant, along with SC200 Controllers and other similar equipment.

2018-2020: Infrastructure Rehabilitation

City Wastewater Crew have been removing and replacing aging, problematic City sewer lines in an effort to minimize I&I and potential back-ups or breaks. The location, and length of these replacements have been in various locations throughout the City.

2020: Aeration Basin Lining

Basins #3 and #4 were sandblasted and relined to preserve the concrete structures that is the initial stage of our Wastewater Treatment.