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Terrain Aeration relief for housebuilders

One problem facing housebuilders both before and after development is ground compaction. Open spaces designated for building may suffer years of neglect, constant foot traffic or use of wheeled machinery resulting in panning deep below the surface. Similarly, during the building process bulldozers, diggers, dumper trucks and concrete mixer lorries flatten the air out of the soil in areas that will eventually become gardens and shared grassed areas. Often the land itself may have had previous buildings, and the subsoil contains old bricks, rubble and landfill. All these factors contribute to waterlogging which normal aeration cannot relieve.

 Terrain Aeration’s Housebuilder’s Division has developed the specialist machinery and a full service needed for deep penetration aeration to relieve the problem of heavy compaction and waterlogging. Designed to access tight areas, their Terralift tracked aerator can enter small gardens through a gateway or garage and provide unique one-metre-deep aeration. At this depth, compressed air is released via a probe to fracture the soil and create fissures, allowing drainage and letting oxygen reach deep into the soil. Such work has been carried out for many years by Terrain Aeration for the UK’s leading housebuilders including Taylor-Wimpey, Barratt and Persimmon. A typical recent contract saw them treating ten small gardens and a small open flower meadow for Barratt David Wilson Homes in East Anglia while a project for Taylor-Wimpey was treating an open space so the housing development could be signed off with the council as ‘decompacted’. In this instance, the full-size Terralift machines were used, driving the JCB road breaker probe into the ground. At one metre depth the compressed air, up to 20Bar/280psi, was released from the probe which, on the tail-end of the blast, injects dried seaweed. This sticks to the fissures created as the Terralift process is repeated at two-metre centre spacing on a staggered grid. The seaweed expands and contracts with the soil’s moisture content to allow drainage and aeration.

 The Terrain Aeration process has been in operation for over thirty years, providing compaction relief for new-build gardens, sports grounds, golf courses, amenity areas and public spaces. The Terrain Aeration Tree Division provides the specialist treatment for Royal Parks and arboriculturalists throughout the UK. Image1


Effective swale treatment by Terrain Aeration

When Pennyfarthing Homes called on Land Products (Wessex) Limited to help resolve an ongoing problem, MD Roger Attrill knew exactly who to bring in. It may look to be not much more than a dried-up pond, but this swale plays an important role in the Alexandra Meadows estate in Lymington. Swales should hold water briefly, then soak away, but this water was retained for weeks after rainfall since the site was completed two years ago as part of the Sustainable Drainage System (SUDS. This is effectively the housing estate’s holding pond to help stop downstream flooding following heavy rain and storm conditions. It was not draining as it should.

“Naturally occurring hard gravels underlying these swales have proved too slow to drain,” says Roger, “we took the opportunity to experiment with Terrain Aeration’s machinery which in a very short period improved permeability greatly.” Land Products provides a comprehensive soft landscaping and grounds maintenance service to Local Authorities, County Councils, the construction industry and commercial clients.

Having called on the services of Terrain Aeration they used their speciality of deep penetration aeration to relieve compaction. The principle works on the basis of penetrating the very hard subsoil with a probe and fracturing it with a blast of compressed air to a maximum of 20Bar (280psi). The process is repeated in spacings so the fissures created interlink and allow full drainage. In this instance, the effect could be seen immediately with a 50mm drop in the standing water in minutes. Within two days, the water had gone completely.

“I’m confident we can make the whole SUDS system work as planned with a bit more time.” Roger says. “I have worked with Terrain Aeration before when they treated compacted gardens for us and they did exactly what they said they would, very straightforward.” Increasingly, Terrain Aeration are called upon by housebuilders and landscapers to treat gardens where during construction heavy machinery has compacted the subsoil around new-build properties.

 

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Terrain’s deep aeration in Yorkshire Sculpture Park

Situated near Wakefield, West Yorkshire, the Yorkshire Sculpture Park is an open-air gallery that showcases work by world-class British and international artists, including Yorkshire-born Henry Moore, Barbara Hepworth and Damien Hirst. The park has one of the largest open-air collection of Moore’s bronzes in Europe. Spread over 500-acres of 18th century designed landscape of Bretton Hall, YSP opened in 1977 and was the first UK sculpture park based on temporary open-air exhibitions that were organized in London parks from the 1940s to 1970 by the Arts Council and London County Council.

Today, the ‘gallery without walls’ has an ever-changing exhibition programme and preparing to reopen after lockdown presented an opportunity for remedial work to be done. Following a site visit by hydrology consultants inspecting a waterlogged area, they brought in Terrain Aeration with their deep aeration treatment system. The area in question was an important part of the Lower Park and a popular area for visitors and curators. It suffers from compaction due to footfall and the weight of sculptures, resulting in the build-up of standing water.

 “It is unusual for the area to be cleared,” says Mark Chesman, Head of Estates and Parks at YSP, “but the sculptures in that area were removed for conservation work, and we seized the opportunity as part of a wider project. In all, it took two-and-a-half days and they treated 4,000 square metres of land.”

Terrain Aeration’s Terralift hammers a hollow probe one metre into the soil using a JCB road breaker gun. At depth, the ground is usually so compacted it needs the hammer to break through. Compressed air is then released to a maximum of 20Bar (280psi) to fracture and fissure the soil and the process is repeated in two-metre spacings, to ensure the fissures interlink. On the end of the air blast, dried seaweed is injected which sticks to the fissure walls, expanding and contracting with moisture content in the soil and keeping the area ‘breathing.’ The 1.5-inch probe holes created by the Terralift machine are backfilled with aggregate to provide a semi-permanent aeration/ventilation shaft, helping to keep the whole aeration process working. The park’s groundkeepers then overseeded the area to finish.

We tend to take trees for granted, in our parks, public spaces and estates but they are often subjected to stress as a result of several factors, such as nutrient shortage, surface compaction due to foot traffic, and waterlogging where water drains off hard surfaces. Yorkshire Sculpture Park features lime trees, beech and Atlas cedar amongst others and these were given Terrain Aeration treatment as well. Breaking up the soil around the roots, and beyond, means excess water will drain away from the roots to help stop anaerobic conditions and rotting of the root system. “We’re confident with what’s been done,” says Mark, “and will be looking at further areas to be treated, probably in the autumn.”

Terrain Aeration 01449 673783 www.terrainaeration.co.uk

Image: Sophie Ryder, Sitting, 2007. Courtesy the artist and Yorkshire Sculpture Park.

Photo © Jonty Wilde, courtesy Yorkshire Sculpture Park. View this photo Sophie Ryder  Sitting  2007. Courtesy the artist and Yorkshire Sculpture Park. Photo © Jonty Wilde  courtesy Yorkshire Sculpture Park


Great Field project for Terrain Aeration

Poundbury, the urban extension on the outskirts of Dorchester is well-known for reflecting the design principles of HRH The Prince of Wales, on whose land, the Duchy of Cornwall, it is built. The Great Field, at some 12 ha, is the largest area of green space in Poundbury and work began on it in 2014, with the building of sports pitches, outdoor gym equipment and a multi-use games area. One area which is developing especially well was sown around five years ago and is now a sea of Common Knapweed, with plentiful Ladies’ and Hedge Bedstraw, Quaking Grass, Bird’s-foot Trefoil and other meadow wildflowers.

During 2020, further significant work has been undertaken with the planting of over 400 trees and 26,000 shrubs and hedging plants. The charity People Need Nature has worked with the Duchy of Cornwall and local seed supplier, Heritage Seeds, to sow another wildflower meadow on the Great Field. Exceptionally wet conditions followed by unusually dry periods, led to compaction and waterlogging, resulting in a slow start for the meadow.  Improving the ground conditions to assist establishment of the trees, shrubs and hedging was identified as particularly important.

The services of specialists Terrain Aeration were called upon to relieve the compaction and panning on the top half of the field. They brought in their Terralift machines, which work on the principle of hammering a hollow probe one metre deep into the soil, using a JCB road breaker gun; the soil is compact at depth and requires the hammer to break through. At one metre depth, a hydraulic blast of compressed air is released at up to 20Bar (280psi). This fractures the soil, creating fissures. The process is repeated at two-metre intervals on a grid pattern with the fissures interlinking to create a system of aeration and drainage.  The Terralift is the only machine which uses such high pressure to enable the process to work. On the tail end of the blast, dried seaweed is injected and this sticks to the walls of the fissures, expanding and contracting with the moisture content in the soil. The probe holes are backfilled with aggregate to maintain the aeration process.

The new Great Field meadow sown with wildflower seed collected from existing meadows in Purbeck, should be flourishing within the next two years. The local sourcing helping to protect local populations of native wildflowers. As part of the usable green space area for the local community, the meadow will be cut in July, with the low-growing flowers, such as Red Clover and Bird’s-foot Trefoil, continuing to flower and provide nectar and pollen for insects. 20191128_094711 Poundbury Great Field


It's always Terrain when it pours

Enable Leisure and Culture (ELC) is a registered charity, contracted by Wandsworth Council to manage and develop the council’s parks, commons and playgrounds. Working in conjunction with sub-contractors such as idverde. ELC takes responsibility for monitoring the grounds maintenance across a total of 200 sites. Enable also advises Wandsworth Council on its responsibilities with respect to legislation relating to biodiversity and best practice in the ecological maintenance of parks. Among the sites under their watchful eye are the sports pitches, of which there are 95 football pitches, 10 cricket squares, bowling greens and running tracks.

“A lot of the sites are on made up ground and experience major problems with drainage,” says Andrew Green, Enable’s Parks Officer, Sports Provisions. “We have carried out aeration down to 300mm but it’s not enough to get to the pans.”

Andrew called on the services of Terrain Aeration whom he has used for around 20 years to deal with waterlogging problems, most recently for Tooting Common, with its six senior football pitches which became waterlogged in the winter season; along with Garratt Park and Fishponds Playing Fields. Terrain Aeration’s Terralift was brought in to apply deep penetration aeration to relieve the problem. The machine uses a JCB road breaker hammer to drive a hollow probe one metre into the soil. This is needed, especially on made up ground, because it is usually so compact at depth it requires the hammer to get through. Once the probe reaches the optimum depth, compressed air is released up to a maximum of 20Bar (280psi). This blast fractures the compacted soil to allow drainage and deep aeration.

The probe is withdrawn and, in the case of the work for Wandsworth, the process repeated using one and a half metre spacings on a staggered grid pattern. This means each shot interconnects the fissures. On the tail end of the blast, dried seaweed is injected which sticks to the walls of the fractures and fissures. Over time, this expands and contracts with the moisture content in the soil to effectively keep the ground drained. At Wandsworth the 1½" probe holes created by the Terralift machine were backfilled with Lytag aggregate to provide a semi-permanent aeration/ventilation shaft, helping to keep the whole aeration process working. Put simply, Andy Green says: “We wouldn’t do it if it didn’t work. We find the Terrain Aeration process is a cost-effective solution, without the need to dig up pitches and lay drainage.

View this photo

Terralift CU_MG_5268


Terrain Aeration visit Cambridge University Botanic Garden

Cambridge University Botanic Garden welcomes 300,000 visitors a year, making it the most visited university botanic garden in the UK. Situated in the centre of Cambridge, the Grade II listed Heritage Garden covers 40 acres and is home to a collection of over 8,000 plant species to facilitate teaching and research. Equally, since its foundation it has provided a beautiful and tranquil place for everyone to enjoy. The Garden boasts four show lawns and the combination of foot traffic, marquee trucks and ride-on mowers leads to compaction. The Garden has been using Terrain Aeration’s decompaction services since as far back as 2013 and chose the deep aeration treatment for the high-profile area of the Main Lawn in front of the majestic glasshouses.
“We know Terrain Aeration’s work from years ago when development had been done at the Station Road Entrance and the lawn at the back of Cory Lodge,” says Adrian Holmes, Landscape and Machinery Supervisor at the Garden. “The lawns had been re-built after the work but were found to be compacted and the soil was not good. We had a waterlogging issue for a couple of years. The Terrain Aeration treatment rectified the problem and we know from experience it’s a long-term solution.”
This year, the Garden’s Main Lawn area was cordoned off, the machine operation creating considerable interest amongst students and visitors, and Terrain Aeration’s Terralift set to work. The weather was very good and dry, and the ground was worked easily without the need to use the Terralift’s JCB hammer drill. The machine’s probe is driven down a metre deep and highly compressed air released up to a maximum of 20Bar (280psi) to fracture the soil, opening it up for aeration, drainage and to get oxygen to the roots of the plant. On the tail end of the air blast, dried seaweed is incorporated which sticks to the walls of the fractures and fissures created by the main air blast. As pressure drops, the seaweed is mixed in the hopper unit where it swirls around with the remaining air and is then released. The seaweed swells in wet weather and keeps the fissures open. On the Main Lawn the same process was repeated in two-metre spacings, so the underground fracturing is thoroughly linked. In some extreme cases this is demonstrated by water fountains appearing from previous probe holes. In this instance the ground was found to be not as compacted as expected and the 2,500sq metre area was completed in two days, not the original three as had been expected.
“The Terrain Aeration guys were very good, prompt and efficient and quite knowledgeable,” says Adrian, “they backfilled the probe holes with Lytag, lightweight aggregate and it was as if they had never been there. It was great to have everything back to normal so quickly.” The aeration treatment completed, the lawn area was immediately open for unrestricted access to the fountains, glasshouses and horticultural and National Plant Collections.

Terrain Cambridge University Botanic Garden IMG_4671 - Copy 2


Return to Stourhead for Terrain Aeration

Many of the views at Stourhead, the Wiltshire estate cared for by National Trust since 1946, will be familiar from the 2005 adaptation of Pride and Prejudice starring Kiera Knightly. The estate was sold to wealthy banker Sir Henry Hoare in 1717 and today includes the Palladian mansion, built around 1725 and the village of Stourton. The world-famous garden was designed by Henry Hoare II and laid out in a classical 18th century design with a large lake.

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Terrain Aeration at Sir Harold Hillier Gardens

Terrain Aeration and the Valley of Fire

The Sir Harold Hillier Gardens are famous around the globe and have the world’s largest collection of hardy trees and shrubs anywhere in the temperate world. The Gardens now hold fourteen National Plant Collections and the latest planting project has been named ‘Valley of Fire’. The name is derived from the planting of over 30 different types of trees and shrubs that will create stunning autumn colour on both sides of what is currently known as Oak Tree Vista.
One of the challenges that faced the scheme was the need to create drainage in several areas of wet, heavy clay, to get the plantings off to a good start. David Jewell, Head of Collections, called upon the services of Terrain Aeration to carry out systematic treatment of the areas around the new plantings.
“I have known of the Terrain Aeration service for many years,” says David, “and have used them before. Their machines do an excellent job with very little disruption, in our case in quite tight areas on very soft ground. The results always speak for themselves.”

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Long lasting effects of deep aeration in evidence at Gelligaer Bowls Club

Scamper in the welsh hillsIt's always nice to be able to back up our marketing with some evidence and we thought you'd like to hear about our re-visit to Gelligaer Bowls Club in South Wales.

See our Scamper in action - view animation.

The last time we were there was eight years ago in 2002 having originally been called in mid-season because the green was not performing well. Poor grass growth, standing water and a strong smell of sulphur (rotten eggs) suggested that something was drastically wrong with the underlying drainage: failure of grass growth resulted in black areas forcing members to play from rubber mats for the first match of the season.

The green was built into the side of a valley with the green forming a terrace with the down slope end on well drained black soil. The down-slope wasn't a problem and was in excellent condition; it looked good and played well and the drainage was how you'd expect.

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AERATION GETS TOP MARKS AT MERSEYSIDE SCHOOLS

Knowsley Park Liverpool It's fair to say that a lot of our day-to-day work tends to be on golf courses or bowling greens but we do actually treat a lot of recreational facilities in public open spaces and schools.

We've just returned from treating nine primary school fields across Merseyside and as a result of our efforts, the children and staff can look forward to a full winter of sports events unhindered by standing water under their feet.

Dave Connor, Construction and Development Officer for Knowsley Council in Liverpool brought us in during last spring to treat twelve winter sports pitches.

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