AECOMClient: Maryland Transportation Authority
The new Governor Harry W. Nice/Senator Thomas “Mac” Middleton Bridge (Nice-Middleton Bridge) improves regional traffic speeds and maritime travel for a key gateway over the Potomac River between Maryland and Virginia. The new four-lane Nice-Middleton Bridge replaces the existing 1.9-mile, two-lane bridge originally opened in 1940 and had reliably stood the test of time. But after seven decades of dedicated service, the bridge no longer met current safety standards. The new Nice-Middleton Bridge now provides twice the traffic capacity with its four 12-foot-wide lanes. It also includes shoulders to improve safety and facilitate access for emergency response, maintenance, and wide-load vehicles. Navigational vertical clearance of 135 feet also has been enhanced to enable tall ships to pass beneath.
AECOMClient: MTA Construction & Development
As one of the busiest train stations serving Long Island Rail Road (LIRR), NJ TRANSIT, and Amtrak, with direct connections to six New York City Transit subway lines, Penn Station hosted approximately 600,000 visitors daily pre-pandemic. With expanding regional rail services, future demand is now projected at over 830,000 daily commuters. The LIRR Concourse improvements were doubled in width and the ceiling height raised to 18 feet. An innovative structural framing system helped increase ceiling height while maintaining structural support to Madison Square Garden, sidewalks, and roadways above ground, and avoiding significant structural work in the train shed. The design and sequencing approach maintained pedestrian circulation at concourse level and traffic movements on 33rd Street throughout construction. Penn Station remained fully operational through construction. Critical to ongoing 24/7 station operations, support and crew facilities for LIRR and the MTA Police Department were upgraded. While overcoming these complexities, no trains were delayed during construction.
Black & VeatchClient: Louisville and Jefferson County Metropolitan Sewer District
The Louisville and Jefferson County Metropolitan Sewer District entered into a Consent Decree with objectives aimed at eliminating more than 5 billion gallons of untreated combined storm sewer and wastewater overflows (CSOs) into local waterways each year. As the sewer district sought one approach to handle CSOs, the project teams offered an alternative to handle overflows CSOs from 25 different locations using a deep bedrock tunnel alternative solution to provide much greater flexibility. The result is a 4-mile-long, 20-foot-diameter, 200-foot-deep CSO storage and conveyance tunnel with a capacity of 55 million gallons. During wet-weather events, a total of 25 CSOs are diverted to the tunnel for storage and conveyance. The new tunnel is designed to prevent 439 million gallons of CSO from discharging to public waterways, such as the Ohio River, in a typical year. As the first deep bedrock tunnel in downtown Louisville, several crossings beneath stakeholder infrastructure were necessary. As of fall 2023, after 16 months of operation, the new tunnel captured over 500 million gallons of CSOs that would have otherwise polluted Louisville’s waterways.
Brown and Caldwell/HDR (Joint Venture)Client: SacSewer
A new treatment system produces cleaner water for discharge to the Sacramento River, as well as for potential reuse as recycled water, such as for landscape and irrigation. The project, branded “EchoWater,” reflects how wastewater would return to a clean, natural state—much like an “echo” returning to its original source. Additionally, its new Nitrifying Sidestream Treatment facility converts ammonia to reduce chemical costs for odor control by $10,000 per day. Meanwhile, its Biological Nutrient Removal process, one of the largest in the country, removes 99 percent of the ammonia and 89 percent of the nitrogen from the wastewater. The EchoWater Project results in cleaner discharge to the Sacramento River, provides recycled water for unrestricted beneficial reuse, and keeps SacSewer in compliance with regulatory permits.
Carollo EngineersClient: City of South Jordan, Utah
The city of South Jordan, Utah, has no culinary water rights of its own and currently obtains all its drinking water from a regional wholesaler. The city had been looking for a drought-tolerant, local water supply of its own to supplement wholesaler deliveries and assist with meeting new demands. A direct potable reuse (DPR) was deemed the right solution, and the project team designed a DPR pilot for demonstration purposes and public outreach. DPR—the process of purifying treated wastewater effluent to drinking water standards—is still relatively new with several implementation challenges. With the Pure SoJo Demonstration Facility, the project team is introducing the following non-reverse osmosis treatment plan to meet the city’s objectives: ozone/biologically active filtration, ultrafiltration, granular activated carbon, ultraviolet disinfection, ion exchange, and chlorine disinfection. This treatment has produced safe, clean drinking water that has met all regulatory requirements with additional levels of safety. The city and Carollo have hosted multiple tours at the pilot facility and will soon be offering taste-testing events. The Demonstration Facility will operate for five years.
D&B Engineers and ArchitectsClient: Suffolk County Department of Public Works, NY
Discharge of untreated organic matter and chemical contaminants from cesspools and septic systems in Deer Park, North Babylon, West Babylon, and Wyandanch seriously impacted human and wildlife health, creating algae blooms, brown tides, and high nitrate levels that deteriorated wetlands, and making shorelines of the Great South Bay dangerously flood prone. The project incorporated a low-pressure sewer system to redirect sanitary waste from more than 2,300+ private residences directly to the Bergen Point Wastewater Treatment Plant. The project involved construction on thousands of private residential properties. A portion of the sewer was connected to Suffolk County Sewer District via a 48-inch sewer interceptor extension. Microtunneling beneath Southern State Parkway minimized traffic disruptions and kept the artery open. The project preserves the Great South Bay’s wetland ecosystems. The low-pressure sewer system mitigates nitrogen buildup and diverts other contaminants.
Dunbar/Walter P MooreClient: VCU Health
The 560,000-square-foot Wonder Tower provides emergency, trauma, and inpatient care services in one state-of-the-art, kidfriendly facility. A part of the VCU hospital network, the project includes a 280-foot-long enclosed pedestrian skybridge that spans over one of the city’s busiest intersections to connect the new Children’s Hospital to the VCU Medical Center Main Hospital building. Constructed overtop and alongside the Children’s Hospital of Richmond’s existing outpatient pavilion, the horizontal and vertical expansion presented a host of engineering challenges. It also is the first major Richmond project incorporating the state’s rigorous new seismic design code. Additional engineering challenges included designing the innovative new tower on a confined urban site while keeping the adjacent hospital buildings operational and minimizing disruptions to surrounding vehicle and pedestrian traffic.
Freese and NicholsClient: North Texas Municipal Water District
Facing some of the most explosive population growth in the U.S., the North Texas Municipal Water District needed a new, longterm water source added to their system to operate in concert with their smart water management and conservation efforts. The result was the new $1.6 billion Bois d’Arc Lake water supply program, a crucial new water source that started serving some 2 million people in more than 71 communities in spring 2023. Two decades in the making, Bois d’Arc Lake, Texas’ first major reservoir in 30 years, initially provided 70 million gallons a day of drinking water for North Texans. The main elements include a 2-mile-long, 90-foot-tall earthen dam and 16,641-acre reservoir; a treatment plant and transmission systems that include two huge pump stations and 60 miles of pipelines for raw and treated water; and multiple sites of forested and emergent wetlands, grasslands, and stream restoration, including the planting of 6.3 million trees.