Water & Wastewater
Ever changing regulations for environmental and health issues make water and wastewater management the most challenging components of our nation’s infrastructure. These issues are further compounded by growing populations and expanding development. The combination of these issues has put significant demands on aging infrastructure and operational procedures that have driven the need for major infrastructure modernizations, rehabilitations, replacements and expansions. At SVS our experience in addressing the technical challenges related to these projects and our appreciation and tact in considering the political pressures has placed us as one of the top value consultants for water and wastewater related projects.
We have conducted studies on every aspect of water resources projects from raw water reservoirs to raw water conveyance systems to water treatment and filtration facilities to disinfection strategies to pumping stations to finished water reservoirs to finished water distribution systems , bio-solids handling and more.
Our wastewater experience includes new plants, plant expansions, process upgrades including digester upgrades and sludge handling, combined sewer overflows, pump stations, pipelines, tunnels, collection systems, interceptors, operations and maintenance facilities and more.
Edgewood Wastewater Treatment Plant
This wastewater treatment plant was originally constructed during or before World War II and has experienced many subsequent expansions and improvements since then, but most of the structures and parts are more than 20 years old. The project will upgrade the plant to meet effluent TN and TP levels of 4 mg/L, and 0.3 mg/L respectively. To achieve these levels, the plant will be upgraded to 1.2 million gallons per day (mgd) capacity with appurtenances to allow the plant to expand to the permitted 3 mgd capacity in the future. Major features include: headworks, influent pump station, sewer piping, denitrification facilities, secondary biological treatment, shellfish protection basins, clarifiers, ultraviolet disinfection system, sludge processing and storage facility, monitoring and controlling system, a building to house the control system, and operations area for personnel and equipment, among others. The study resulted in many intangibles to the project team including identifying unforeseen flaws of the current plant while on a site visit, direct conflict with attempting to refurbish this 70-year old system, and savings of 15% on the construction cost.
Chemical Upgrades to a Water Treatment Plant
This study was a constructability review of ten projects occurring at a water treatment plant on the west coast. The focus of this review was to identify schedule conflicts and make recommendations to ensure delivery of the key projects deadlines.
Key projects included a new hypo tank farm, a new polymer mixing facility, the rehabilitation of the filters with new media and internal components, new foundation systems for two washwater tanks, new bromate facilities in support of the new ozone facility, replacement of over 250 filter valves in the galleries of the two filter buildings, and the seismic rehabilitation of the inlet channels and other filter basin upgrades.
Eight of the ten projects all occur in the same general areas of the plant and all require the use of the same space between structures. The team developed a new schedule identifying the critical path forward with new milestone dates ensuring the timely completion the key projects.
Due to new governmental regulations, there is an initiative to reduce combined sewer overflows (CSOs) into the Kings Run Stream and Mill Creek and to restore the historical connection between the two creeks as well as improve water quality. This funding agency was under a federal Consent Decree to reduce the CSOs by 2018. During heavy rains, the combined sewer overflows into the Kings Run Stream and into the Mill Creek. The two CSOs are nested, so overflows at one outfall contribute to overflows at the other. About 300 million gallons of CSOs overflow annually. This project integrated green infrastructure (e.g., stream restoration, wetlands, bioswales, rain gardens and stormwater detention basins) with gray (e.g., new storm sewers) to provide cost-effective solutions with community benefits. The Kings Run Project reduced the overflows through the use of stormwater detention basins, sewer separation, and a CSO storage tank. The project also included stream stabilization of the Kings Run Stream. The VE team recommended savings of about 15% of the construction cost.
Water Treatment Plant
The number of residents in this water service area is expected to double over the next 20 years, and water demands are projected to continue to increase well into the future. As a result, two major projects were initiated: (1) design and construction of a new Water Treatment Plant (WTP) and finished water transmission system; and (2) design and construction of a new Raw Water Supply System (RWSS) consisting of raw water intake, pumping stations, transmission main and quarry storage system.
The VE effort included a series of VE Studies and identified several hundred ideas for improvements to the WTP resulting on the development value alternatives. The new plant is being developed for an initial design capacity of 20 mgd with capability for future expansion to 40 mgd. Future capacity expansion including space for process upgrades is needed for regulatory compliance and will include post filter ion exchange, and new intermediate pumping to avoid hydraulic grade line impacts for the initial plant. The value team provided alternatives related to the UV disinfection train, the clearwell, pipe materials, pump motors, and the admin and maintenance building.
South Secondary Improvements Project
This five-day VE Study looked at the South Secondary Improvements Project of the Robert W. Hite Treatment Plant, which is the largest in the U.S. west of the Mississippi River serving Denver and several surrounding counties. The project involved upgrading the plant from a HiPOS system to an activated sludge system, as well as increasing its capacity and attaining new, more stringent discharge limits that are to be effective in 2016. This involved the construction of new aeration basins, PEPS, a blower building, RAS/WAS facility, and a mixed liquor facility, all while maintaining plant operation. The Value Study resulted in a significant reconfiguration of the Primary Effluent Pump Station (PEPS). The design team reviewed one specific value alternative and subsequently developed an optional alternative that actually resulted in greater savings to the project. The study developed savings of over $21 million.
100 mgd WWTP Capacity Improvements & Biological Nutrient Removal Process Upgrades
This Project aims to improve the advanced wastewater treatment facility by removing more ammonia as well as nitrates. The discharge permits for the facility are becoming increasingly stringent. The Facility Upgrade Plan recommended that the facility be converted from the HiPOS to a traditional activated sludge process, with provisions for biological nutrient removal. SVS conducted a 5-day study on the project, providing alternatives for over $30 million in savings. Additionally, the Value Team proposed alternatives that significantly reconfigured the Primary Effluent Pump Station, improving the overall functionality and capacity of the facility.
Newtown Creek Bending Weirs
To reduce annual overflow, this project includes modification to four specific outfall structures to maximize the diversion of flow to the sewer interceptor and to increase the storage in the trunk sewer system without decreasing the discharge capacity of the outfall during high flow events. The structures proposed to receive these modifications convey flows to two adjacent Wastewater Treatment Plants (WWTPs). All of the outfalls discharge combined sewer overflows (CSOs) to an adjacent creek.
An analysis of the project cost during the VE Study revealed that two of the four outfalls account for over 40% of the project cost but only account for 20% of the total average annual overflow volume (AAOV) reduction required by the project. Also, the required reduction goal could be accomplished by modifications to just two of the outfall structures. Additionally, the cost analysis revealed that temporary construction such as excavation support and flow bypass during construction accounted for 30% to 60% of the cost at each site and over 40% of the total project cost.
The Value Team focused on constructability issues to reduce the cost of temporary bypass flows by developing a staging concept that would eliminate the need for a constructed bypass. Other concepts modified the design of the weirs to achieve significant savings while still meeting the AAOV requirement. The Value Team also recommended the elimination of any work on two of the structures since the project objectives could be accomplished with the other two structures. Final resolution is still pending however there is a likely potential that this study will result in 40% to 60% savings on the project.
Colorado Springs MESA Water Treatment Plant
The scope of this Value Study was to assess alternative water treatment processes that will allow this 70-year old WTP to maximize the use of locally available water supplies, many of which have high fluoride concentrations. The recommendation in the Master Plan Report is to build an essentially new 42 mgd filtration plant with a patented pre-treatment process using relatively high doses of alum to remove fluoride.
The Value Team recommended several alternatives that would avoid construction of a new filtration plant by enabling this well maintained WTP to take advantage of locally available water supplies with higher fluoride concentrates and remain operational for an additional 10-15 years until the local water utility is in a better position to fund a full plant replacement.
City of Calgary Sewer Master Plan
The City of Calgary is currently developing a master plan for upgrading two wastewater treatment plants to address current capacity deficiencies and to accommodate the projected population growth in 2035. During the development of this project, new data was provided for projected population in 2075.
This Value Planning Study was conducted to revisit the sewer trunk projects and the treatment plant master plan based on this new long term population projection. The objective of this Value Study was to: assess the timing of the trunk sewers from upstream of the City with future servicing strategies considered, including additional right-of-way (ROW) needs; evaluate the future overall servicing options up to Year 2075 including the impacts of a new Wastewater Treatment Plant; and evaluate the impacts of future treatment plant capacity options.
The Value Planning Study reassessed the assumptions used in the calculation of the flow rates for the two trunk sewer projects and concluded that the base flow may be overly conservative assumptions. Secondly, the study introduced a storage concept for excluding the short duration, high flow, peaks from the design flow calculations. These two changes in the calculation of the design flows resulted in significant reductions in the size of the trunk sewers that would allow the City to install a trunk within the available budget that will serve the population well beyond the original expectations. Additionally, the team concluded that based on the City’s plan for developing effluent reuse and the likelihood for the reuse customer base to develop in northern Calgary, further consideration should be given to a WWTP in the north. This would reduce the demand on the Nose Creek Trunk Sewer, thus reducing the required pipe size, but it would also locate an effluent source near the expected customers.
The project is to improve SCADA (Supervisory Control and Data Acquisition) systems for seven wastewater treatment plants (WWTP) and to replace obsolete PLC and I/O equipment. The new systems are standardized on one PLC family for new projects with standardized PLC code and HMI configuration. The systems are a fault-tolerant control system with multiple levels of redundancy and based on open architecture with industrial hardened components. The systems consist of two redundant fiber rings at most plants and were designed to accommodate remote operations at all plants in the future. Additionally, security is based on physical security and firewalls at each plant.
The Value Team concluded the systems are overly complicated and redundant and recommended that less complicated and less redundant systems be considered to perform the same functions at the same level of reliability. The team also provided several value alternatives to improve internal and external security. Additionally, the team noted that additional clarification of responsibility between the contractor and the engineers is necessary during cut-over from the obsolete control systems.
Water Development Project
This Client wants to more fully develop their water rights and make safe, reliable and cost effective water deliveries to customer agencies while developing a financially successful water supply system.
The Client purchased significant water rights, including a pump station and a diversion structure, a raw water pipeline and easements, and several wells located on the property as part of their water rights portfolio. The Client conducted a thorough preliminary evaluation of these water rights, the future estimated water demands for potential customers, and the costs and infrastructure necessary to provide the water supply to the interested local customers. This preliminary evaluation reviewed several options before selecting a preferred alternative consisting of a pipeline that will convey treated surface water from the local Water Treatment Plant to a storage reservoir.
Under an ongoing VE contract, the Client requested that SVS conduct a Value Study with several objectives including: evaluating the strengths and weaknesses of the preferred alternative and make recommendations to the Client as it commences pre-design tasks and negotiation of water supply contracts for this alternative; evaluating the effectiveness and integration of the components of the recommended alternative to meet the Client’s business and water supply goals and identify alternative approaches to developing the most reliable and safe water supply system in a cost effective manner; and provide suggestions on pre-design tasks, controls, marketing approaches, and asset investigations and planning for the District to implement as it proceeds to develop the Water Project.
As a result of the Value Study, the Value Team recommended alternatives which resulted in over $5 million implemented savings while improving the Client’s bottom line and delivering the required water supply capacity. An additional $50 million in potential savings was still under consideration as of this writing.