Infrastructure and civil engineering projects present significant opportunities for waste minimization, re-use and recycling. Designing out waste in these sectors not only makes economic sense but it should be a sustainable environmental cornerstone of any well designed project.

All good project design presents opportunities to remove waste from the construction and civil engineering landscape, where large quantities of high value materials provide a basis for significant cost savings and environmental benefits.

There are a number of key principles that a good project design should consider at the pre-construction phase, not least, preparing a site waste management plan which considers;

• Materials Reduction, Reuse and Recycling

• Off Site Construction

• Material and Supply Chain Optimization

• Procurement Strategy

• Post construction

These basic principles act as a catalyst, providing a basis for technical solutions which should seek to ensure that waste minimization opportunities are maximized.

Materials Reduction, Reuse and Recycling

The re-use of materials from both the natural and built environment underpins the sustainable management of construction projects and reduces the burden on the environment.

Construction of the surrounding landscape provides many opportunities for re-use of demolition material, recovery and reuse of materials from the existing hard landscape and / or recovery of a variety of materials from the soft landscape.

A Site Waste Management Plan is essential and will ensure regulatory compliance, good waste management practice and efficient use of resources.

Good project design will consider where;

• materials from demolition of existing on-site structures can be re-used or recycled in the surrounding landscape design

• materials from the clearing of the existing surrounding landscape can be reused in the landscape design

• maximum value is being obtained from the re-use of valuable materials from the existing landscape

• excavated materials can be re-used or recycled for landscape features (use materials as a paving, walls, tarmac, concrete and aggregate rubble can all be used for sub-foundation, drainage base or infill for new landforms)

Soil analysis should be undertaken prior to any demolition or construction works to identify types and quantities of potential re-usable or recyclable materials for retention on-site. Setting aside good quality, high value materials from the existing landscape for reuse or re-sale is common sense and good practice.

Good top-soil is a highly valued commodity and should be graded and stockpiled for re-use. Excavated rocks can be used for drainage layers, landscape infill or ornamental landscape features.

Off Site Construction

Good project design should ideally seek to coordinate and minimize the amount of trades and activities taking place on site at any given time. This can significantly reduce costs, speed up the project programme and improve site health and safety. For example;

• can internal walls, roof sections and retaining structures be precast or prefabricated off site ?

• Can use be made of pre-engineered solutions for landscape features and pathways

Material and Supply Chain Optimization

Good project design should result in the optimum use of the supply chain and the efficient use of materials, increasing resource efficiency and minimizing material storage and waste during the construction phase without compromising the design concept.

Much can be achieved through clear specification and standardization of materials and through effective supplier coordination. For example;

• Can the range of materials specified be standardized to encourage the re-use of off cuts during the construction phase ?

• Can the hard landscape design and layout be simplified without compromising the design concept ?

• Discuss methods of waste minimization with suppliers and manufacturers

• Consider methods of packaging reduction with suppliers and manufacturers

Good site management and construction programmes will minimize conflicts and the need for re-work and / or re-design

Procurement Strategy

Procurement strategy influences the construction process through specification, contractor scheduling and setting unambiguous targets for suppliers and contractors. Some basic examples include;

• Considering on-site operations and supplier related waste arisings and how these will be stored, treated, re-used, recycled or re-sold ?

• Consulting with specialist contractors and suppliers in regard to good practice, waste minimization and optimizing the supply chain ?

• Review project specifications and contracts and identify materials and processes that reduce waste ? (Consider setting contractual targets and providing financial incentives / default remedies to reduce waste)

• Implement vendor / supplier assessment- seek to embed best practice through the tendering process, clearly defined methods of waste minimization should be an essential feature

• Specify and maximize the use recycled products

• Develop procurement processes and materials requisition procedures that avoid waste – develop controls and scrutinies requisition systems to facilitate just-in-time delivery of materials and reduce surplus.

• Agree take back schemes with suppliers and manufacturers

Post Construction

It is essential to consider post construction maintenance at the project design stage. The construction design should always consider potential future changes of use and, wherever possible, seek to minimize associated and excessive waste being produced.

• Can the design be adapted during its life span ?

• Does the design incorporate reusable / recyclable elements and materials ?

• Can landscape features be maintained, upgraded or replaced without creating waste ?

• Have the project specifications and contracts been reviewed in favour of elements, materials and processes that minimize waste ?