Wicking up a storm - sports fields and lawns that irrigate themselves and don’t send you a water bill
Written by Sally Boer
Often the best ideas are old ideas that have stood the test of time.
In the current COVID-19 paradigm, local sportsclubs are doing it tough. While eagerly waiting for it to be safe for games to resume, keeping the turf alive requires water and water bills are mounting. In some jurisdictions, it's up to the local clubs to fund these ongoing costs while in other locations local governments carry the burden. Throw population growth and climate change in the mix, the ongoing supply of potable water for irrigation is looking shaky.
A system that I've found to be very resilient and cost effective is the ‘self-watering’ turfed kick and throw field constructed in 2014 at Gladstone’s East Shores Parkland which uses a wicking bed technique. This field, whilst a large scale experiment at the time, has exceeded all expectations and proven to be a very attractive proposition for sportsfields and parklands alike. And like all good things, it is simple, has ancient origins, is very low maintenance and the water is free.
The field in Gladstone, besides looking very green and healthy from above, holds a secret below – it collects and stores water below the root zone in a ‘wicking bed’ providing soil moisture whenever needed.
The humble wicking bed is an ancient Ethiopian farming technique; feeding water into a storage layer beneath the surface and letting plants ‘wick’ the moisture up when its needed. It lessens evaporation losses and lets the plants take water when they need it. A super efficient system.
Back in 2013, we recognised the potential to deliver large scale wicking beds to irrigate turf, capturing local stormwater runoff from adjacent roads to feed an underground storage within the soil profile of the sports field. As the turf removes water from the soil it is replaced by water replenished from the storage below by capillary action. An overflow system ensures that the turf layer and growing media above will not be submerged during rainfall events and also facilitates enhanced drainage of the turf soil layer.
This is biomimicry in action – with no-imported energy (i.e. no pumps or pop-up sprinklers required), the turf is sustained between rainfall events and the design increases the usability and resilience of these areas after heavy rainfall through improved sub-soil drainage.
Six years after construction in 2014 and the parklands are flourishing.
The result is an admirably simple but integrated solution that delivers everything you could ask for in a sustainable landscape scheme; passive irrigation, stormwater treatment, an alternative water source and improved soil profiles for healthy turf and active use spaces.
We have designed and delivered several schemes including a wicking lawn in an exemplar home in Townsville – Innovation House 2.0, which was constructed in 2018. Designed with landscape architect Josh Byrne and the Innovation House team for Stockland, the home includes a range of water-conscious gardening techniques including a passively irrigated tree. Two years after construction and the wicking lawn and tree are looking great and amazing locals by staying green, without watering, in the harsh dry tropics climate.
We are currently scoping opportunities for sportsclubs and have developed concept designs for AFL ovals and soccer fields. A demonstration wicking lawn is soon to be constructed by Townsville City Council to showcase this water sensitive approach. We are also actively monitoring and researching the built systems to gather more knowledge about their performance and the benefits to soil and turf health and will be receiving turf cores for analysis from both the Gladstone and Townsville wicking systems.
Wicking lawns and sportsfields – what’s not to like?
- Reduced stormwater and pollutant loads to the environment
- Reduced potable water use
- Reduce energy requirements for irrigation
- Reduced fertiliser application
- Retention of soil moisture
- Increased turf resilience to dry periods
- Consistently greener turf
- No water logging or boggy fields
- Quick return to play following rainfall
- Ease of maintenance and mowing
- Deep root system and healthy turf
- Supporting healthy lifestyles and active play