Wastewater

Our experience in wastewater collection systems is based on a variety of municipal and private planning, design, and construction projects. These projects range from single family pressure distribution septic systems to larger municipal collection and transmission lines. We maintain knowledge of the industry's new technologies including directional drilling, slip-lining, robotic spot repair, pipe bursting, and other alternative and creative construction methods to provide our clients with flexibility of methods and construction costs to meet individual project constraints.

Our planning project experience includes system modeling for capacity analysis as well as inflow and infiltration analysis to identify cost beneficial improvements to systems. In addition to collection systems, we have been involved in the construction administration of contact chambers, recirculation sand filters, package treatment plants, laboratory facilities, secondary treatment lagoons, and outfall diffuses. Post project experience ranges from setting up operations and maintenance programs to biosolids studies.

District Engineering and On-Call Services - Freeland, Washington

Freeland Water & Sewer District On-Call ServicesDCG is the District Engineer for the Freeland Water & Sewer District providing all engineering services for the District including comprehensive planning, capital improvements design, construction phase management, and on-call services. DCG completed the District’s Water System Plan update in 2004 and has been assisting with implementation of the plan. DCG has provided ongoing on-call services for improvements projects including a booster pump station, distribution projects, a new reservoir and equipment building, chlorination equipment, telemetry upgrades, and well rehabilitation.

The distribution projects have included a horizontal bore under SR 525, pipe bursting with HDPE pipe, and conventional PVC C900 and ductile iron pipe distribution, services, fire hydrants and appurtenances. DCG’s other on-call services include plan review, water and fire flow availability determination, rate study assistance, funding application assistance, wells and water rights acquisition, and attending District meetings. DCG also provides the Freeland Water and Sewer District with planning support for its on-going work to establish a sewer utility; finance study management, property acquisition, engineering studies, grant proposals, and grant management.

Arsenic Treatment Facility Study and Design - Langley, Washington

DCG was contracted to provide engineering services for the proposed 200 gallon per minute arsenic treatment system in order to reduce arsenic concentration from 0.027 mg/L to below federally mandated maximum contamination level of 0.01 mg/L.

DCG prepared a treatment report comparing several arsenic removal technologies, managed a pilot test of the preferred technology, prepared Washington State Department of Health Drinking Water State Revolving Fund Loan (DWSRF) application materials, provided design of the facility for public bidding, prepared construction documents and assisted the District with the bidding process. The design calls for construction of a 350 SF treatment building, a pre-fabricated filter system, chemical dosing and injection, treatment process controls, backwash water handling and discharge, and emergency power (generator) for an existing pump facility.
Client: Saratoga Water District

Small Water System Management Plan - Langley, Washington

DCG prepared the Small Water System Management Plan, enabling the District to acquire project funding through the Washington State Department of Health Drinking Water State Revolving Fund Loan (DWSRF) program for the proposed Arsenic Treatment Facility, also designed by DCG.

The tasks completed by DCG included evaluation of existing and future service area boundaries, system capacity calculations, Water Rights Self assessment, and a capital improvement plan to meet the District’s existing and future needs.
Client: Saratoga Water District