Rehabilitate Ash Mountain Wastewater Systems

Sequoia & Kings Canyon National Park, California

 

The Ash Mountain Wastewater Treatment Plant serves over 1.6 million visitors annually and 34 permanent Park Service employee residences, many visitor facilities, and various park facility buildings. A Condition Assessment Report conducted in 2011 identified one grouped project addressing the existing deficiencies of the treatment plant system.

In July 2019, HECO Engineers performed a site visit and prepared a scoping trip report and updated Class D Construction Cost Estimates to help validate the estimated cost identified in the Project Management Institute Statements (PMIS) for the Ash Mountain Wastewater Systems. The entire process stretched across seven separate projects and totaled over 4.5 million dollars.

 

Ash Mountain Project Management Institute Statements (PMIS)

 

• PMIS #184085 rehabilitates and replaces critical components installed in 1974 within the treatment facility, specifically replacing the failing existing 17,500 gallons per day wastewater treatment system, rehabilitating the electrical system, deteriorated headworks and overflow, a new floating cover for the detention pond, the deteriorated treatment dosing building, and deteriorated spray disposal fields, and replacing the chlorination system.

• PMIS #246176 rehabilitates the three (3) wastewater lift stations and force mains in the developed areas of Ash Mountain and Buckeye Housing of the Park, including the duplex pumps, motors, controls, float system, the force main blow off, drain vaults, and mechanical equipment.

• PMIS #181622 Repairs include the renewal of the 3,000 square foot treated effluent spray field components (sprinkler heads, risers, solenoid valves, and valve boxes). Repairs and replacement are located in areas located beneath secondary roadways, steep terrain, under creeks, and meadows. The terrain is difficult to access with heavy equipment. The pipe sizes vary from four to six inches, at depths of two to eight feet deep.

• PMIS #229631 replaces metal signage, discolored and unreadable, and performs repairs to perimeter security four (4) strand barbed wire fencing at the Ash Mountain spray field, and removing severely overgrown/invasive vegetation and fallen/dead trees.

• PMIS #257424 rehabilitates the Ash Mountain Buckeye employee housing road, grinding, and pulverizing 950 square yards of four-inch-thick existing asphalt to utilize as a four- inch structural road base, repaving with four inches of new asphalt. This includes minor safety restriping with traffic flow arrows, stop bars and 100 lineal feet of parking.

• PMIS #257415 rehabilitates the Ash Mountain treatment plant service road, grinding and pulverizing 700 square yards of four-inch-thick existing asphalt to use as a four-inch structural road base, repaving with four inches of new asphalt.

• PMIS #256139 replaces controls and monitoring equipment for the treatment plant, replacing components according to typical industry life-cycle replacement standards, including replacing wastewater treatment plant controls for the process batching and pumping to the disposal field. This includes local monitoring equipment for pump and motor failures that prevent system overflows of wastewater.

 

Services Provided by HECO Engineers:

• Project Management
• Process Engineering
• Electrical Engineering
• Civil Engineering
• SCADA Control/Instrumentation Engineering
• Cost Estimation