A Significant Project to Harvest Water into Tree Root Systems and stop Erosion of the Public Footpath.
Since 1862 Queen’s Park in Ipswich has been a landmark park of cultural significance and a popular destination for families for recreation. There are many magnificent, heritage trees growing in the park providing wonderful habitat for many varieties of native wildlife to use and creating shade for human visitors from the hot, Queensland sun. The responsibility and conservation of these significant trees and upkeep and care of the park belongs to Ipswich City Council.
Unfortunately, some significant Poinciana trees in the park were failing to thrive. These trees are situated on a hillside on a nature strip close to the popular nature reserve, with a road on one side and a concrete footpath on the other. Heavily compacted soil (penetrometer readings of past 950 PSI) was preventing rainwater from infiltrating into the ground and therefore not providing the underground network of tree roots with much needed hydration. This hydrophobic soil caused the knock-on effect of flooding of the footpath during major wet weather events and caused erosion of the footpath. Another troublesome problem that regularly occurred was the washing away of surface mulch from the ground onto the nearby footpath and road which was subsequently washed into the stormwater drain.
The Plant Health and Urban Soil Science Research team at Heritage Tree Care were tasked with coming up with a long term practical solution that would allow rainwater to easily infiltrate into the soils, preserve the footpath from erosion and be financially prudent. Senior Consulting Arborist at Heritage Tree Care Daniel Oaten formulated a plan which involved the Heritage Plant Health team, the Porous Permeable Paving team, the Vacuum Excavation team and of course the Arboriculture team working together to achieve a successful result.
The main aim of this project was to improve the health of the trees and to do this effectively, the soil needed to be decompacted using an innovative VOGT geo injector. Using the injector, the ground was given a much-needed boost of soil amendments and inoculums this in turn gave the trees a much needed health boost. This soil decompaction and health injection was completed several times throughout the project.
Vacuum excavation was utilized to safely install a trench alongside the pavement as well as lateral drainage trenches to individual trees without damaging any tree roots systems. The vacuum excavation team also dug out a water outlet baffle bed to soak up any access water in an extreme wet weather event. Once the ground was prepared and the trenches dug, a variety of geotextile materials, Aggi pipe and gravels were placed in the trenches to stabilize the soil. To complete the project a layer of Arbor Flex Porous Rubber was installed and then a layer of PermaMulch porous paving.
Why Use Porous Permeable Paving?
Porous permeable paving allows air and water to flow through the porous material at a rate of over 300 litres per minute per square metre, enabling the water to soak into the soil below. It was decided that Porous PermaMulch would be the most suitable material to use as the top layer over the rubber base not only for its fantastic absorption abilities (1000 litres per metre per minute) but also for its aesthetic qualities as looking like normal Aged Forest Mulch, it would naturally blend into the park landscape.
The project was an overwhelming success and the months of planning and preparation paid off. A demonstration for the Ipswich City Council Arboriculture Division was completed where 2000 litres was released onto the site. This highlighted how the water is now easily and quickly absorbed into the ground, watering the trees as opposed to running down the path to the stormwater drain, taking debris with it.
Watch the video to see the development of the project in pictures and also the overwhelmingly excellent result of 2000 litres of water being released onto the area.
Contact Us for More Information
For all your Water Sensitive Urban Design, Plant Health Care and Tree Care needs, call Heritage Tree Care on 0737155444 or email firstname.lastname@example.org for a free, no-obligation quote, our qualified Arborists will be delighted to advise you on the best course of action for your trees and property protection. We cover Brisbane, Logan, Ipswich, Redlands, Toowoomba and Gold Coast area in Queensland, Australia.