Ocean FM - Weekly Tips 24 - Rainwater Harvesting

Did you know?

Rainwater harvesting can can play a vital role in reducing pressure on public water utilities and infrastructure, while also making cities more resilient to the effects of climate change
Rain Gardens or planters increase habitat for urban pollinators and wildlife and can create green spaces in otherwise sterile, concrete areas
The quality of diverted rain water is typically high enough to be used for a wide variety of non-potable (non-drinking) purposes including WC flushing, laundry, garden irrigation and vehicle washing
In countries like Ireland, with temperate climate systems, it’s estimated that reusing rainwater can lower mains water use in commercial applications by up to 80% and in domestic homes by over half.This can be a huge saving for public resources
Urban micro-climates tend to be significantly warmer than vegetated areas because their hard surfaces absorb, store and radiate heat. Vegetation in planters provides shade and cools the air through a process called “evapotranspiration.” Maintaining urban green spaces can be water intensive so rainwater harvesting also provides a sustainable source of water to irrigate these valuable green spaces

Why is this important?

As climate change impacts in Ireland we are going to see more periods of very intense rainfall and we need to find ways to cope with this. Rainwater harvesting has a recognised role in reducing flood risk as it leads to lower peak flow rates
In heavy rainfall, much water doesn’t reach treatment facilities. When urban rainwater from storm drains mixes with sewage in a ‘combined’ system, this leads to pollution of local watercourses
When rainwater passes over our roofs or our streets and other impermeable surfaces, it can collect pollutants, chemicals or oils that get washed into our urban drainage system. Rain planters use rainwater productively and the plants growing there also act as a bio filter, cleaning pollutants out of the rain water
We can use rain water to create green spaces in otherwise sterile urban environments, increasing levels of well-being, providing habitat for urban pollinators and wildlife and acting as a carbon sink
Citizen-led climate action can have a significant impact on urban problems and that creative partnerships with nature will lead our cities toward a healthier, greener and more sustainable future

What can I do?

Consider building a rain planter in your garden, street or community. You will need access to a downpipe, and space on the ground next to it. You can follow Dublin City Council’s ‘A how-to-guide for Rainwater Planters” below, if you need some instructions
Call in to Sligo library to see the rain planter in action, speak to the staff there and people you know about it. This spreads the idea to more areas
Where you have an opportunity, consider rainwater harvesting as part of sustainable design choices and emphasise this with in communications or consultations with local planners and designers
Consider other simple or sophisticated rain diversion and conservation ideas such as a water butt at your home
See if there are options for recording the amount of rainwater you harvest. This is interesting information for yourself and can be valuable in trying to understand what impact it has on the volume and the flow into the drainage network

For More Information

Water Sensitive Urban Design

https://lawaters.ie/nature-based-suds/

How to build a Rain Planter

https://www.biurban.ie/the-process-how-they-work

Climate Change and Rainfall in the EU

Assessment of Dublin Rain Planter Project

http://dccbeta.ie/project/article/rain-box-planters

Managing Rainwater on Farms