We reported before that a significant proportion of global companies are at risk from water scarcity which is why more and more organisations are looking to implement systems such as rainwater harvesting.
Rainwater harvesting can reduce water usage and costs, and will also reduce your organisation’s dependency on mains water, leaving you less at risk of water shortages or other problems with mains water. Furthermore, as rainwater has less limescale, the amount of deposit and eventual damage to your equipment and appliances will be reduced.
Rainwater can be used to cool water in the manufacturing process, wash vehicles, flush toilets, water gardens etc. However, it may not be suitable for all organisations.
Some things to think about before rushing into installing a rainwater harvesting system are outlined below:
- Quantify the amount of water you currently use by checking water bills or data collected via your smart data logger and compare this with the maximum water you can harvest in a year to determine whether the ‘pay back’ is good enough.
- Check the cost of installing such a system. For instance, if you have an older building, there may be extra plumbing involved which could drive up costs.
- Consider where the water will be used, as this will determine the required quality and level of treatment. In some cases, such as toilet use, the required treatment will be minimal; in others, for example where water will be used in food processing, the treatment will be high. If you need high levels of treatment, rainwater harvesting may not be suitable as the costs and annual maintenance of the system could outweigh the savings.
- For industries such as food manufacturing, it is essential that a risk assessment of the water source and its intended uses is carried out. Trials should be conducted to make sure the treatment process and its management work well and comply with guidelines and requirements.
- Decide where the rainwater storage tank will be located – will this involve any modifications to your existing drainpipes?
- For commercial premises, you may also be able to benefit from tax allowances under the Enhanced Capital Allowance (ECA) scheme. The rainwater harvesting system must be on the Water Technology List before your business can claim the 100% first year capital allowance on its cost.
- It is the responsibility of the business installing the rainwater harvesting system to apply to have it certified as eligible for an ECA, not the business which manufactures or supplies it. So, it is essential that you ask your manufacturer or supplier to ensure that the design meets the eligibility criteria, as you must provide supporting evidence for this to Defra.
As well as cost savings, the reuse of rainwater can improve the overall Building Research Establishment Environmental Assessment Method (BREEAM) performance for a building. BREEAM is an environmental assessment for new and existing buildings, which was developed by the Building Research Establishment and is the leading – and most widely used – environmental assessment method for best practice in sustainable design.
There are clearly several benefits to rainwater harvesting, but it can be a costly and complicated process so organisations need to properly research the costs and benefits before diving straight into installing a system.
For general enquiries about the Water Technology List, you can call the WTL Advice Line on Tel 0844 875 5885. Alternatively, you can email your questions to wtl@aeat.co.uk
For more information on rainwater harvesting e-mail info@businesscostconsultants.co.uk.