Gilbert + Sutherland

With highly experienced, industry-recognised experts, Gilbert & Sutherland provides specialist services in hydraulics, hydrology, water supply and catchment resource planning, stormwater management and groundwater analysis and management.

Water is a central environmental issue and a key capability of Gilbert & Sutherland. Founded on thorough field experience in surface and ground water quality assessment, monitoring and management together with appropriate computer modelling, our multidisciplinary team approach facilitates the development of innovative outcomes to complex challenges.

Hydraulics and Flooding

Flooding impacts and other hydraulic issues are critical considerations for any development. Uncertainty surrounding climate change and an increasingly complex regulatory environment is resulting in intense scrutiny of proposed developments by councils and statutory authorities. Given the extremes of the Australian climate and the concentration of population in low-lying coastal areas, a great deal of this scrutiny focuses on flooding and other hydraulic issues.

Gilbert & Sutherland’s hydraulics and hydrology unit is comprised of a team of five engineers headed by Director and Principal Water Resource Engineer Owen Droop. Our team is experienced in hydraulic and hydrological modelling, water supply planning and mine water management. Owen’s first disciplines are hydraulics and hydrology and he has given expert evidence to mining and planning commissions over the last fifteen years.

Gilbert & Sutherland’s hydraulics and flooding capabilities include:

• flood studies tailored to needs and budgets (local, regional or catchment wide)
• hydraulic computer modeling and analysis using a range of specialist software and tools
• integration of flood mitigation and hydraulic management measures at the development concept stage
• peer review and problem solving
• preparation and presentation of expert hydraulic and flooding evidence for mediation and court purposes
• tidal estuary and bay hydrodynamics, sediment transport and siltation investigations
• water quality investigations including lake dynamics, tidal flushing and pollutant dynamics
• stormwater quantity assessment and management

Total Water Cycle Management

Stormwater

Stormwater is an increasingly important factor in modern environmental management. No new development or change in land use is approved without careful consideration of stormwater issues. Water quality must be maintained while runoff quantity must not increase, but the regulatory regime is complex and ever evolving.

Assessing and managing stormwater requires extensive experience, elite skills and the latest technology. New research and technological change are constantly advancing stormwater management techniques and capabilities.

Gilbert & Sutherland’s experts have witnessed the increasing prominence of stormwater issues over the last decade. Our team includes senior engineers and scientists with extensive experience in the development industry, environmental consulting and hydrological modeling and research.

Our stormwater assessments integrate years of experience, advanced computer modeling, thorough research and the latest in Water Sensitive Urban Design (WSUD) considerations. Our advice and management plans are professional, clear and direct, and are supported by our solid track record of steering clients through application processes.

Gilbert & Sutherland’s stormwater management capabilities include:

• Water quality assessments
• assessment of lake water quality
• assessment of water quality pre and post development
• monitoring and assessment of stream/waterbody water quality

Water Sensitive Urban Design (WSUD)

• design and assessment of WSUD ‘treatment trains’, incorporating vegetated swales, buffer zones, bioretention systems, infiltration systems, constructed wetlands and ponds
• design of projects to incorporate sustainable water management strategies

Stormwater harvesting and reuse

• irrigation assessment
• rainwater tank assessment

Stormwater flows

• design of retention systems
• flood height prediction
• hydrological modeling pre and post development

Stormwater management

• construction phase monitoring and auditing
• preparation of stormwater management plans from single projects to entire catchments or regions

Stormwater rehabilitation projects

• assessment of existing conditions and design of stormwater quality improvement systems.

Groundwater

Groundwater considerations are often complex, especially in low-lying coastal areas, sensitive environments, contaminated sites and industrial contexts. Assessing sites, identifying risks and designing effective management strategies are difficult tasks, requiring expert knowledge, skills and experience.

Gilbert & Sutherland employs specialist engineers and scientists trained and qualified in groundwater assessment, modeling and management issues. Where necessary, we work with hydrogeologists and others to fully consider any crossover between our groundwater capabilities and potentially linked geological and geotechnical issues.

Gilbert & Sutherland’s groundwater capabilities include:

• acid sulfate soils impact assessment and management
• aquifer investigations
• aquifer recharge
• bore installation and establishment
• dewatering management plans
• drawdown effects assessment
• effluent disposal
• groundwater bore licensing (NSW)
• groundwater contamination assessment and management
• groundwater dependent ecosystem assessments
• groundwater flow assessments
• groundwater modeling
• groundwater quality monitoring
• integration of groundwater issues with surface hydrology and hydraulics (stormwater quality and quantity and flooding)
• permeability testing

Wastewater management

Non-sewered developments pose particular challenges in terms of wastewater management. Disposing of effluent in a safe and responsible manner requires significant experience, specialist skills and careful scientific assessment. Errors or failures in the planning and management of effluent disposal systems can lead to environmental damage and expose owners, developers and others to risks, costs, and legal liabilities.

Whether it’s a single residence on a small rural lot or a major eco-development in a sensitive environment, Gilbert & Sutherland combines years of experience, thorough research and the latest computer modeling to ensure each assessment meets or exceeds all statutory obligations and regulatory requirements.

We specialise in constrained or challenging sites and sensitive environments, facilitating innovative solutions to complex problems. Our effluent disposal specialists are part of a team of experienced scientists and engineers with access to a range of resources, including a comprehensive suite of services provided by our in-house environmental and geophysical drilling capabilities.

Gilbert & Sutherland’s capabilities include:

• effluent disposal assessments for intensive agriculture including piggeries and feedlots
• expert testimony in legal disputes
• in situ assessment of physical properties
• land assessment and management plans for dispersal/re-use of solid and liquid wastes
• nutrient balance modeling and impact assessment
• preparation of Site & Soil Evaluation and Design Reports in accordance with the Australian Standard
• site evaluation for effluent disposal suitability for single dwellings, subdivisions and large community title developments or resorts
• sizing and design of irrigation areas for single dwellings and large community title developments or resorts
• soil survey, description, classification and sampling
• water balance modeling and pond sizing

Hydrology, Strategic Water Supply and Catchment Resource Planning

The Australian continent exhibits some of the most extreme and variable hydrology in the world and the effective management of our limited water resources is an increasingly important and complex challenge.

Gilbert & Sutherland’s hydrology unit is headed by Owen Droop – a Principal Water Resources Engineer with recognised expertise and significant experience in the fields of catchment resource planning and water management, as well as strategic water supply planning. Droop has been an integral part of the development of numerous Water Resource Plans and Resource Operating Plans developed for Queensland catchments, as well as in the development and assessment of the South East Queensland Water Strategy.

Gilbert & Sutherland’s hydrology and water supply/management planning capabilities include:

• project specific water supply studies tailored to needs and budgets (local, regional or catchment wide)
• computer modeling and analysis using a range of specialist software and tools, including the IQQM adopted for use within the WRP and ROP process, and the WATHNET modeling tool used for the development and assessment of the SEQ Water Strategy
• conceptual design of water supply and water management schemes to meet multiple objectives of supply performance and environmental outcomes
• catchment wide modeling for the assessment of existing and potential future development infrastructure and operational rules
• development of stochastically generated hydrologic and climatic data sets for multiple locations and sub-catchments
• development of modeling methodology and simulation models for the assessment of project specific water supply system for the quantification of risk of shortfall
• assessment of potential water management operational options for minimisation of supply shortfall risk and support and advice towards long-term strategic and short to medium term operational water management planning.