Hespeler trunk sanitary sewer line, Ontario, Canada
City of Cambridge
GHD helped the City of Cambridge in Ontario, Canada to implement an innovative trenchless technology solution for the 45-years-old Hespeler trunk sanitary sewer line, which serves more than 35,000 residents.
After assessing the sewer and reviewing potential options, our team identified cured-in-place pipe as the preferred methodology for rehabilitating the 2 km long, 600 mm and 675 mm diameter trunk sewer. This involves installing a soft, resin-soaked, sock-like liner within the existing sewer using high-pressure air.
This solution saved approximately CAD1 million compared to traditional replacement methods, which would have entailed significant costs and approvals challenges, including the need to clear-cut surrounding forestry within an environmentally sensitive area.
Following the feasibility report, GHD developed the detailed design and tender documentation, and secured the necessary approvals. We also provided contract administration and site inspection services.
Novaliches - Balara Aqueduct 4, Manila, Philippines
NovaBala Joint Venture Corporation (NBJVC)
One of the largest water supply infrastructure projects undertaken by Manila Water, a new tunnel aqueduct is being constructed, traversing one of the world’s most densely populated cities.
The Novaliches to Balara Aqueduct 4 (NBAQ4) will enable Manila Water to secure water supplies for Metro Manila and also progressively rehabilitate its three existing aqueducts between La Mesa Dam and its Balara Water Treatment Plant.
NBAQ4 will convey 1000 ML/d of water to Balara Treatment Plants 1 and 2 from the La Mesa Reservoir. The project entails the construction of a new intake facility at La Mesa Reservoir, a 7.3 km long by 3.1 m diameter tunnel, a 30 m above-ground outlet tower as well a mini-hydro power plant, access bridge and road and downstream ancillary pipework and civil roads. The tunnel will be constructed using a TBM (Tunnel Boring Machine), which is the first time Manila Water has used such technology in its history.
GHD was engaged by construction contractor NBJVC, an international consortium of companies (Chunwo, CMC Ravenna, First Balfour), to develop the tender detail design and is currently involved in the early stages of construction as NBJVC’s technical advisor.
Once constructed, the project will provide drinking water to approximately 7 million people within Metro Manila.
Westchester County Water District No. 1 Ultraviolet (UV) Disinfection project, New York, USA
Westchester County Department of Environmental Facilities
Westchester County Water District No. 1 serves approximately 175,000 people and is operated by the County Department of Environmental Facilities for the benefit of the Cities of White Plains, Mount Vernon and Yonkers and the Village of Scarsdale.
To implement an alternative water supply that would obtain water directly from the Kensico reservoir required two new, separate UV disinfection facilities, in order to bring the water quality in line with recent federal regulations (LT2ESWTR) and to meet the hydraulic constraints of the existing system.
Cooperation between many stakeholders was necessary to locate two approvable, technically feasible construction sites. Both facilities were designed in the existing hydraulic grade line so that no additional pumping was required. The equipment and controls were designed to be above grade to ease operator access. Exceptional cooperation between municipalities and regulatory agencies facilitated fast tracking of the project, which was necessary to meet the compliance schedule of the USEPA.
GHD identified, evaluated, designed and constructed this enhanced surface water treatment that provides higher water quality and protection for customers, while reducing costs and meeting EPA regulations.
Wickenburg Ranch Water Reclamation Facility, Arizona, USA
Wickenburg Ranch community
The 2160 acre Wickenburg Ranch community in Arizona was isolated from the existing water and wastewater infrastructure and needed a robust wastewater treatment system to support its future growth and development. The Town of Wickenburg also wanted a long-term solution that would reduce the amount of groundwater used by golf courses and landscaping for irrigation.
A new 100,000-gallons-per-day (gpd) water reclamation facility has been built to provide Class A+ reclaimed water, reducing the demand on the aquifer by up to 29.2 million gallons annually during Phase 1 operations and by 106.58 million gallons annually during the future Phase 2 expansion.
A high-quality water reclamation system was selected as the wastewater treatment process that provided the most beneficial reuse. Membrane bioreactor technology was chosen as it requires less daily interaction, while also producing consistent and compliant effluent, even under extremely variable loading conditions. Use of design optimisation tools during the master planning efforts resulted in a symmetrical design that promotes ease of operations and maintenance, while providing sufficient space planning for the ultimate facility build-out at 1.2 million gpd.