Propeller Wash

Cleanup of contaminated sediment sites may include dredging, capping, or in-situ treatment, or a combination of these three techniques. Long-term stability of sediments is key to the success of these remedial actions…

Eutrophication Studies

The US EPA describes nutrient pollution as “one of America’s most widespread, costly and challenging environmental problems.” This issue is of significant concern world-wide, with considerable resources now being committed in Asia and Europe to study eutrophication in streams, rivers, lakes, bays and coastal waters and related economic, environmental and human health issues.

Total Maximum Daily Load Studies (TMDL)

The need for detailed plans describing the restoration of impaired waters is widely recognized in developed countries. TMDL studies outline the maximum amount of a pollutant a body of water can receive without violating water quality standards, and an allocation of that amount to the pollutant’s sources. Determining the Wasteload Allocation, the portion of a receiving water’s assimilative capacity that is allocated to one of its existing or future point sources of pollution, is often required in a TMDL study. Numerical modeling is an indispensable component of these studies.


Sustaining the viability of a maritime recreational and industrial activity depends upon maintaining navigation channels, including depths of approach channels, and berths at marine terminals and marinas…

Light Analysis and Submerged Aquatic Vegetation

Submerged aquatic vegetation (SAV) are marine, estuarine, and riverine angiosperms, and macrophytes. These are grasses that grow to the surface of shallow water and only emerge from the surface at low tide. They serve vital ecosystem services in the shallow waters by providing refuge for small fish and shellfish from larger predators.

Marine Hydrokinetics

Marine hydrokinetics (MHK) comprises a range of energy technologies for electricity generation from wave and tidal power. MHK installations can require large areas of ocean, which competes with other marine resources and can be detrimental to marine life and habitats. MHKs are often located at the mouths of ecologically-sensitive estuary systems. This can alter the hydrodynamics and salinity of the system and negatively impact animal and plant life.

Watershed Planning

Environmental regulations require the development and implementation of watershed plans to meet water quality standards and protect water resources. Engineers and regulators working with impaired or threatened waters must undertake watershed planning that considers all stages in the land development process from land use planning through to land development and post occupancy.

Thermal Compliance

Water temperature has significant and systematic effects on biological processes at all levels of organization, from phytoplankton to whole ecosystems. Temperature influences several other parameters and can alter the physical and chemical properties of water such as dissolved oxygen and photosynthesis production. Some organisms, particularly aquatic plants, flourish in warmer temperatures, while some fishes such as trout or salmon prefer colder streams.

Tailwater Analysis

Assessing the potential for tail-water scour downstream of a dam is a key issue in hydro projects. Dam failure due to poorly designed spillways and forebays can result in significant loss of life and property. Furthermore, dams often withdraw water from the hypolimnion where dissolved oxygen levels are lower, impacting water quality in the tailwater.

Flow Patterns & Velocity

Coastal waters and estuaries, as well as dams and rivers, are environments with significant impact on the regional economic and recreation activities as well as bio-diversity. These systems have a great range of…

Oil Spill

Offshore energy activities can pose significant risk to the environment as demonstrated by Deepwater Horizon and many other historic oil spills. These spills can kill marine mammals and fish and contaminate their food supply for extended periods of time. Determining the transport and fate of spilled oil and/or oil spill responsiveness planning is a pressing need.

Dredging Impacts

Dredging is commonly undertaken to provide deep enough water for vessels to transit safely into, out of, and around harbors by maintaining the depths of navigation channels and berths. Sediment can consist…

Shoreline Erosion

Erosion of shorelines can be a significant problem in both open and confined waters. Natural events such as rainfall and run-off, and large ships navigating restricted waterways can cause sediment resuspension….

Extreme Weather Events

Extreme weather events such as flooding, hurricanes and storm surge put extra pressure on coastal defenses and adjoining regions. Forecasting and warning services for natural disasters can help save lives but often require installation of flood forecasting and warning systems, along with decision support systems.