Request for Proposals - Sandy Wastewater Program - Consulting Environmental and Engineering Services

The City of Sandy requests proposals from qualified environmental and engineering consultants for professional services required for the permitting of a new Sandy River Outfall through the Oregon Department of Environmental Quality (OR-DEQ) National Pollution Discharge Elimination System (NPDES) program and other related services.

To be considered, four (4) hard copies and one (1) digital (.pdf file) copy of the proposal must be received by Mike Walker, Director of Public Works at 39250 Pioneer Blvd, Sandy, OR 97055 by the date and time of Friday, May 28, 2021, at 4:00 pm. Please mark the submittal on the outside of the sealed envelope with the following: “Professional Consulting Services for the Sandy Wastewater Program NPDES Permitting Support".

Background

Sandy is located approximately 25 miles east of Portland, OR with a population of approximately 11,000.  

The City has started a large program to improve their wastewater collection, conveyance, and treatment system. The 2019 Wastewater System Facilities Plan (WSFP) identified improvements to be implemented in three phases until 2040; including sanitary sewer rehabilitation, upgrades to the existing treatment plant, a new satellite treatment facility, and a new outfall. 

The existing Wastewater Treatment Plant (WWTP) was built in 1971 and expanded in 1998. Under the current NPDES permit, the effluent is used for irrigation by a local nursery May through October. November through April, the effluent is discharged to Tickle Creek which flows into the Clackamas River.  

The City of Sandy's discharge into Tickle Creek is limited by receiving stream dilution and mass load requirements under OAR 340-041-0350. As the City grows, Tickle Creek will no longer have the capacity to handle all of the City’s discharge. In response, the City has searched for other solutions for their treated water. Draft technical memoranda (TMs) summarizing the various discharge locations and developed preliminary engineering assessments of various components of the program. These TMs are located on the City’s website.

The WSFP Recommended Plan includes the construction of an Eastside Membrane Bioreactor Satellite Treatment Facility, a new year-round Sandy River Outfall, and constructed wetlands. The treatment plant will use state-of-art membrane technology, producing high-quality water. This treated water is anticipated for discharge to the Sandy River, which has a greater capacity than Tickle Creek and can allow a potential year-round discharge. Additionally, partial discharge to constructed wetlands is planned during the warmer months for temperature mitigation.  

The existing WWTP will continue to discharge to Tickle Creek under the current permit and only the new satellite treatment facility will discharge to the Sandy River Basin. In introductory talks with the Oregon Department of Environmental Quality, the new Sandy River Outfall will be permitted on a new and separate permit from the City’s current NPDES permit. The next stage of the project is to acquire DEQ approval for a new discharge into the Sandy River. 

The City is currently conducting a water quality and temperature data collection and sampling program in the Sandy River that will continue into 2023. Proposers may email Project Contacts and request temperature data files and water quality sampling results for their reference.