Renovation of a power facility in Rufus, Oregon. Conceptual plans call for the renovation of a power facility.

The John Day Powerhouse is internally conditioned and ventilated via a mixture of HVAC systems. Most of the existing systems are remnants of the Powerhouse's original construction (over 50 years ago) except for miscellaneous modifications and repairs performed over the years (Gate Repair Pit modifications, liquid chiller replacements, etc.). The current overall state of the existing HVAC systems is considered poor. Numerous key components have either completely failed (liquid chiller, electrostatic filtration units, pneumatic controls) or are on the verge of failing (pumps, control valves, isolation valves). The failure of the pneumatic controls is one of the more significant issues plaguing the facility. O&M personnel are having to manually control the Powerhouse's main ventilation system (modulate outside air intakes, manually switchover modes of operation (heating or cooling), etc.). This loss of automation is producing poor system and in turn is requiring increased O&M support. To add to these issues, few systems comply with current codes and standards including the life safety and fire protection type. Missing smoke detection, unprotected floor penetrations, missing refrigerant monitoring systems, lack of automatic HVAC shutdown capabilities during a smoke/fire event and improper Battery Storage exhaust are just a few examples. Additionally, space usage and occupancy have both changed over the years and each have had negative impacts on the HVAC systems (original ventilation pathways cutoff, increased cooling demands on the systems, etc.). This project firstly entails complete replacement of the primary and installation of secondary chillers on two chilled water loops that cool the majority of the powerhouse galleries. The scrapping of the old system and the installation of new chiller skid packages (four skids amounting to nearly 600 tons refrigeration), electrical feeds, chilled water pumps, piping, installation and air handler units is scoped, with re-use of certain elements of these systems based on provided designs in combination with replacement. These systems must be tied into a new automated HVAC control system. While the existing systems are water cooled, only half of the new systems will be water-cooled, so roof-mounted air-cooled condensers in a new location and new installation with all necessary building penetrations, pass-thrus and piping are part of the scope for this work. Secondly, additional work comprises the modification of the HVAC system into a comprehensive smoke removal system for the powerhouse, including intake and outtake ducting and systematic fire protection measures at all penetrations. This work must include integration of the HVAC controls with the building fire protection system. The HVAC controls must be a comprehensive integrated digital control system replacing all existing pneumatic control systems. Free cooling with passive outside air during cold nights common to the region of Rufus, Oregon and for outside air for smoke ventilation entail the scope including modifications to existing intakes and louvers and building penetrations. Thirdly, small scale HVAC units such as mini-splits will be provided for local cooling and heating requirements in specific spaces. These units will require their own electrical supplies, pipe runs, insulation and penetrations. These units must also report data to the central HVAC control system. Comprehensive smoke control must be provided as part of the work. The proposed system must be constructed in an active, operational powerhouse with 6000A, 13.8kV busbars and other heavy electrical equipment, including at levels below headwater where nuisance water intrusion risks are present. Pumps in certain areas must remain operational during the planned work, resulting in noise hazards. The existing fire suppression system must remain active during the planned work. Work includes installation work for ductwork and work to protect floor penetrations in relatively close proximity to electrical busbars so that delineation and safety control of work sites is a priority. Newly installed systems must future-proof the installation against future refrigerant phase-outs. Work involves extensive structural penetrations and structural modifications necessary to support these penetrations, both permanent penetrations for ductwork and plenums and temporary removal of wall sections to remove old equipment and install new equipment. Finally, temporary cooling must be provided to the powerhouse during the full scope of the work, at approximately 50% of the rated tonnage capacity of the chilled water system. This will entail portable skid mounted chillers located externally to the powerhouse with temporary pass-thru for their electrical supply from the powerhouse, and for making connections for chilled water piping to the existing internal powerhouse pipes, with cutovers as the work progresses. Estimated Construction Cost (ECC): The current ECC is between $25,000,000 and $100,000,000. Ref. FAR 36.204 Disclosure of and DFARS 236.204 Disclosure of . Anticipated Construction Schedule: CENWP intends to advertise October 2024 and award December 2025 Construction Contract with estimated construction completion by the September 2026. *The for this project is based on a financial range. The is listed as the highest possible cost from the range provided by a stakeholder or official project document.