Extracted text (via pymupdf)
7257 characters
4742 North 24th Street Suite 270 Phoenix, Arizona 85016 Main: 877 627 3772 Water Memorandum To: Town of Wickenburg From: Casey Whiteman, PE Date: December 10, 2025 Subject: Preliminary Water Memo Project No.: 2026.02 Terrible’s (the Project) is a gas station facility being developed north and east of SR-93, and east of Scenic Loop Road in Wickenburg, Arizona. The Project consists of approximately 5.75 acres in a portion of Section 21 in Township 1 South, Range 7 East of the Gila and Salt River Meridian. The Project will consist of a new convenience store, gas pumps, parking, and space for a future car wash. The Project is within the City of Wickenburg (City) in Yavapai County. However, the Project lies outside of any designated water service provider’s service area. All onsite water infrastructure required for serving the Project will be privately owned and operated by Terrible’s. The proposed water system infrastructure has been prepared and evaluated consistent with guidelines adopted from the Design Standards for Water and Wastewater Systems (City of Phoenix, 2021), 2018 International Fire Code (ICC, 2018), and the Arizona Administrative Code (AAC, 2017). Anticipated water demands for the Project are shown below in Table 1. More detailed calculations have been provided as an attachment. Table 1: Water Demand Summary Land Use Average Day Demand Peak Demand (gpm) (gpd) (gpm) (gpd) Commercial 0.4 625 0.7 1,063 Car Wash TBD TBD TBD TBD General Landscaping 8.7 12,552 14.8 21,338 Public ROW 0.6 779 0.9 1,359 TOTAL: 9.7 13,976 16.5 23,759 The convenience store and site amenities will be constructed prior to the car wash facility to reduce initial water demands. There is no existing City water infrastructure near the Project vicinity. Therefore, the Project will be serviced by a private onsite water campus utilizing the existing well and storage tank located Project No. 2026.02 December 10, 2025 Page 2 | 2 just outside the southeast property corner. The existing water tank is 102,000 gallons. Information on this tank has been provided as an attachment. A new pump station and the necessary treatment/chlorination facilities will be installed as required. These new facilities will be located in the southeast corner of the Site. Additional information on these systems will be provided with the final water report for the Project. The required firm well capacity for the Project is calculated assuming that the well operates no more than 18 hours per day. Table 2 summarizes the required well capacity needs for the Project. Table 2: Well Capacity Requirements Well Peak Demand Required Well Capacity (Pumping 18 hrs/day) (gpm) (gpm) 1 16.5 22.0 The onsite booster pumps will have sufficient capacity to meet the peak hour demand plus the required fire flow. Table 3 below summarizes the booster pump capacity required for the Project. The firm pumping capacity will need to be met with the largest pump out of service. Table 3: Booster Pump Requirements Peak Demand Fire Flow Firm Pumping Capacity 16.5 gpm 750 gpm 767 gpm HC Water Demand Calculations - Preliminary Terrible's Wickenburg, Arizona December 2025 (SF) (acre) (gpd) (gpm) (gpd) (gpm) Commerical 5,000 0.11 625 0.4 1,063 0.7 General Landscaping 125,000 2.87 12,552 8.7 21,338 14.8 Public ROW 26,000 0.60 799 0.6 1,359 0.9 Total - - 13,976 9.7 23,759 16.5 Notes: Demand Factors: Commerical 125 gal/1000 SF General Landscaping 4,374 gal/acre Public ROW 1,339 gal/acre Peaking Factors: Peak Hour Demand: 2 x Average Day Demand Fire Flow Demand: Building Area 5,000 sq. ft Building Construction Type IIB Fire Flow 1,500 gpm/2 hours Automatic Sprinkler Yes Reduced Fire Flow 750 gpm/1 hours Max Day Demand 16.5 gpm Max Day Plus Fire Flow 766.5 gpm/1 hours Area Land Use Average Day Demand Peak Hour Demand 1Design criteria based on the City of Phoenix Water and Sewer Design Flows (2021). Instructions The tank pad diameter must be at least six feet larger than the diameter of the tank for installation. 1. Remove all loam, vegetation and sharp objects from the tank pad location. 2. Wherever possible, the tank site should be excavated into natural ground. 3. When excavating a site, adequate drainage must be installed to allow water to be diverted around the tank. 4. When using fill to level a tank site, adequate retaining must be constructed to maintain pad integrity. 5. Tank base material must be crushed stone or similar, with a maximum particle size of 0.25” 6. The tank base must be at least 3” thick and level within 1/2” 7. Once the tank base is complete, ensure any damage by vehicles or livestock is adequately repaired. On the day of installation The customer is required to have available: Someone to advise the orientation of the fittings prior to installation starting Sufficient water to fill 10% of the tank volume while the installer is on site IMPORTANT Once the tank installation is complete, place a layer of free-draining aggregate around the perimeter of the tank to reduce base erosion. Site Preparation Aquamate Tanks Site Preparation (844) 320-TANK (8265) Model Code D205 D307 D409 D512 Tank Diameter 17’1” 25’7” 34’2” 42’8” Pad Diameter 24’ 32’ 41’ 49’ Prior to installation • Excavate pipework trench in planned scour location. • Lay scour pipework at least 12” below the planned base level on a suitably compacted base to minimise settlement. • Finished the scour flange flush with the prepared tank base level. • Studs must be at least 2’ long, threaded within 1/8” of flange. • Backfill trench after pipework installation with suitable engineering fill and compact accordingly. Scour drain installation 1. Wrap exposed studs with geotextile offcuts or similar to protect liner during installation. 2. Install tank structure as normal. 3. Position the geotextile underlay as normal. After installation, find the studs, cut a hole around each one and push studs through the geotextile layer. Cut center hole last. 4. When installing the liner, lift the base section over the protruding studs as to not damage the liner. 5. After liner installation, find the studs, cut holes around each one and push studs through the tank liner. Do not cut the center hole at this stage. 6. Remove the geotextile offcuts from studs, place the rubber gasket and sealing flange over the studs. 7. Place a bead of Sika sealant about base of the exposed stud and tighten the washers & nuts onto each one. 8. Cut the center hole in the liner once the sealing flange is firm in place. Scour Drain Installation Site Preparation (844) 320-TANK (8265) finished studded flange prior to liner installation, flush with base level, studs 2” long minimum bolted scour order of assembly: geotextile underlay – tank liner – rubber gasket – sealing flange – sealant – washers & nuts IMPORTANT Compact the subgrade immediately next to flange to provide a firm, unyielding surface for liner to be placed on. Failure to compact area near flange may create differential settlement and lead to liner bridging and ultimately liner failure.