Treating vs. removing wastewater – what’s right for your site?

Your guide to managing wastewater on your construction or industrial site

Visit any construction or industrial site in Australia and you will find water.

• Water is used daily on the surface of construction sites for activities like washing aggregate; preparing and curing concrete; thinning paint; wet cutting; cleaning tools and equipment; ground compaction; dust suppression; and for keeping workers hydrated.

• Below the surface, groundwater is extracted through dewatering processes to keep construction sites dry and allow excavation work to be performed safely.

• Water is also used for a wide range of activities in manufacturing and other heavy industries.

All of these activities create wastewater, which can contain a range of pollutants such as:

• Silt, clay and other suspended particles from dewatering

• Hydrocarbons from petrol, diesel, oil and grease leaks

• Per- and polyfluoroalkyl substances (PFAS), used in a wide range of products for their weatherproofing, stain resistance and corrosion prevention properties

• Titanium dioxide, used in paints, dyes and self-cleaning surfaces

• Heavy metals including cadmium, lead, nickel and mercury

• Nutrients like nitrogen and phosphorous – when these nutrients accumulate in water, they allow the growth in microorganisms that deplete oxygen and kill marine life.

Should wastewater be treated or removed from your site?

When it is left untreated, wastewater can seep into the ground causing soil degradation. It can also contaminate groundwater and enter waterways through stormwater drains and run-off, disrupting these local ecosystems and creating a risk to marine life and human health.

To minimise the environmental impact, wastewater can be professionally removed from construction and industrial sites. It can also be put through an onsite chemical treatment and filtration processes to reduce the contamination levels, allowing it to be discharged into sewer lines or returned to local bodies of water.

Here are some factors to consider when choosing your approach to wastewater management.

Regulatory requirements

All construction and industrial businesses have an obligation to minimise the environmental impact of their work. The regulations and guidelines that determine your wastewater requirements will vary depending on the industry and the location that you are in.

• In Australia, environmental protection laws, policies and guidelines are administered jointly by federal, state and local government.

• Local water authorities may outline additional quality requirements for the discharge of water into sewer lines and bodies of water.

• It is your responsibility to understand and meet the relevant water management requirements for your site – more information can be found here.

Water quality

A range of different water quality factors can shape your approach to wastewater management.

• Chemical treatment and filtration processes are capable of reducing most contaminants from water, making it an efficient and cost-effective way to manage the wastewater generated by construction and industrial sites.

• When wastewater has a high level of turbidity, a more rigorous filtration and chemical treatment process may be required to allow it to be discharged.

• pH is another important determinant of wastewater quality. Water that is too acidic can corrode pipes, bringing along the materials that it strips, while water that is too alkaline can leave minerals behind that cause a build-up of scale. Chemical treatment is an effective way to balance pH, protecting vital water infrastructure and allowing for the safe discharge of wastewater from your site.

Thoroughly testing water quality before commencing work allows you to set important benchmarks. It can also help to determine the right wastewater management approach for your site.

Cost

The cost and potential inconvenience of permanently removing wastewater from site can make onsite water treatment a more viable option. This often occurs when large volumes of wastewater need to be removed, or when your site is located too far outside of metropolitan areas for it to be transported.

Coates can work with your team to design and implement an efficient water management solution that allows you to safely and cost effectively extract, treat and discharge high volumes of wastewater.

Water management expertise

Understanding and meeting the environmental requirements for wastewater can be particularly difficult for businesses without inhouse expertise. With a team of chemical and geotechnical engineers, technicians and solutions specialists, Coates Engineering Solutions can provide expert advice to supports the design and delivery of comprehensive water management solutions for customers Australia-wide.

For help designing and implementing an effective water management plan for your next project, reach out to Coates today.