Clearwood Community Association, On-Call Water System Repair and Improvement

Clearwood Community operates and maintains a water system serving 1,350 customers.  We have provided them with a variety of engineering services such as surveying and design for the replacement of 4,700 lineal feet of six-inch water main with eight-inch service lines on narrow, rolling residential streets with steep grades.  The project included preparation of plans, profile, and detail sheets, as well as cost estimates, specifications, and coordination with the homeowner’s association. Bidding support and post-construction record documents were also provided.  Our design required careful coordination with Puget Sound Energy as the water main and new underground electrical transmission lines were constructed simultaneously.  The water system construction was designed to be installed in sections to minimize shut down periods for homeowners when the new water main was brought on-line.  The design also included installation of new Air-Vac assemblies meter setters with PRVs and hydrants.

Other assignments have included comprehensive planning, design, and commissioning of a new 450 gpm well, a 400,000-gallon reservoir, and water main extensions.  We have also performed design, construction, and commissioning of the system’s water pH adjustment facilities, which treats the water with a 25% solution of sodium hydroxide.

Thousand Trails,
Resort Water System Evaluation

Skillings provided a water system plan evaluation report for replacement of their existing 60 GPM water treatment plant, supplying potable water to a full campground and maintaining the 50,000-gallon reservoir.  We evaluated several water treatment options, identified three manufacturers, and prepared a budgetary cost estimate for each option.  Our review compared each option’s ability to meet all treatment requirements along with:  the relative size of the units for the smallest footprint, the lowest capital cost, and the earliest delivery schedule.  The recommended option met all of these criteria, so we suggested an initial pilot study for the system.

• Summit Water and Supply Company,
  Tank 4 Replacement

Summit Water desired to replace the existing 150,000 gallon concrete tank with a welded steel tank of the same diameter with a capacity of approximately 200,000 gallons.  The new tank provided additional standby storage and greater redundancy for providing peak and fire flows throughout the 522 Pressure Zone. The existing Tank 4 is a 150,000 gallon tank constructed of vertical concrete panels and was erected in 1961.  The seams between the vertical panels used wood to seal the joints.  When the tank was taken out-of-service for maintenance, the wood dried out and became ineffective in preventing leaks due to repeated wet/dry cycles.

Skillings for the designed the new 0.20 MG Welded Steel Tank.  This consisted of preparing the plans and details for the reservoir, site development, erosion control, grading and drainage piping design, water piping connections, and associated improvements. Skillings also was responsible for the supervison of geotechnical investigations, surveying, design engineering, bidding documents, contractor submittal reviews and assistance during construction.

• Summit Water and Supply Company, Well 16 Project Report and Water System Modeling

Summit Water & Supply Company (Summit) serves about 15,000 people in central Pierce County.  As engineer of record for this public water system, Skillings prepared comprehensive plans, specifications and designs, water demand forecasts, and water rights applications.  We also evaluated regional supply options and possible implementation strategies, conducted cost of service and other financial studies, developed proposed water rates and fees, and designed water treatment facilities for disinfection and corrosion control.

First, a 5000 gpm pumping station was developed to meet build-out demands.  At the client’s request, Skillings developed a design for a 2500 gpm pump station as an initial capacity.  This station was configured to consist of two Goulds with 1750 gpm, 75 hp VFD vertical turbine pumps, with allowance for a third pump by installing a spare “can” for future use.  The tank fill and discharge are controlled by Summit’s Supervisory Control and Data Acquisition (SCADA) system, which allows the tank to operate as an additional source for the system during peak periods.  Valves with electronic control interface coupled with the pump’s VFD controllers provide a set flow rate while maintaining back pressure and altitude control. Skillings supervised construction and startup of these facilities. We also recently undertook a rate study which included a cost of service and other financial studies, which was used to develop a water rate structure with associated fee schedule

• Thurston County,
  Tilley Rd Maintenance Facility