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Below are some photos and videos taken along a transect of the floodplain on Peter and Kate Marshall’s property. I hope you enjoy these images (taken 36 hrs after a 180mm overnight event), with the creek running crystal clear and spread out across the floodplain on Sunningdale.

To put what you’re seeing in context, most other watercourses in the region are restricted predominantly to the channel due to the erosion and incision caused by past land management practices. Although man-made, the hydrology in this landscape is much closer to the way it operated pre Euro settlement, in an intact chain of ponds or swampy meadow system. The noise of the frogs in the videos is testament to the significant aquatic and wetland habitat which has also been created.

Photo locations taken across a transect of the floodplain at Sunningdale

Locations of photos taken across a transect of the floodplain at Sunningdale. (For some scale, the image is 350m wide, and the main channel located at the meandering tree-line, flowing from bottom to top).

To flick through a larger slideshow of the images, click on any of the thumbnails below

Short video locations taken across a transect of the floodplain at Sunningdale

Locations of short videos taken across a transect of the floodplain at Sunningdale

Finally, another interesting little clip is of the ground literally bubbling as the subsurface flow rehydrates the gravel and sediments below the surface. This stored moisture benefits the land’s production and drought proofing resilience, while also providing a more sustained base-flow to the landscape below.

See the articles tagged as Key floodplain processes for more information on what is being achieved from a landscape perspective.

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Disclaimer: Where water flow is concerned there are substantial risks involved. While the information and images we publish are formulated in good faith, with the intention of raising awareness of landscape rehydration processes, the contents do not take into account all the social, environmental and regulatory factors which need to be considered before putting that information into practice.  Accordingly, no person should rely on anything contained within as a substitute for specific professional advice.

Article and Images © Cam Wilson, Earth Integral, 2013

A stroll, post flood

A stroll, post flood

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It’s hard to encapsulate all that is happening on Peter and Kate Marshall’s property Sunningdale in one go, but the following series of photos will give you a bit of a taste.

Peter is a pretty special guy. He’s got an understanding of the wider landscape processes which equals Peter Andrews, but he’s also a trained forester and is as widely read and knowledgable as anyone I have met. Add that combination to a desire to fix up some of the considerable degradation caused by his family in past generations and his wife Kate who is equally passionate and equally keen to heal their landscape and you have a pretty powerful combination.

Since commencing their work 22 years ago, the Marshall’s haven’t had it easy. Despite recognition from some of the top mycologists, hydrologists and foresters from here and abroad, within their own community they were largely ostracised early on, from members of the farming community on the one hand because they were seen as the thin edge of a green wedge, and from members of Landcare network on the other because they were using exotic species which Peter knew to have more potential in some land repair roles. Electric fences were cut, waterways were poisoned, authorities were called resulting in the threat of large fines, their children were bullied on the school bus and nuts were even taken off tractor wheels.

An amazing sign of the times is that on Friday night, the Marshall’s received a Champions of the Catchment award from the Upper Shoalhaven Landcare network. This award was introduced to recognise those who have done outstanding work in land repair which differs from the standard few lines of Eucalypts which usually fit the award criteria.

The next day, a tour of their place was conducted. “This is uplifting” was the way that one participant summed it up. Here’s a glance at a small portion of the uplifting work they they have carried out.

Peter leads off the tour, past the considerable biomass produced by Salix and Populus species after only 11 years of growth. These trees moderate the climate significantly through wind protection and transpiration effects.

Here, Salix plantings replicate the gallery forests which existed at the time of European settlement. Exotic species have been chosen due to the changed conditions making the original dominant species, Casuarina, very difficult to establish (heavier more acidic sediment, hare and rabbit predation, reduced frost protection due to complete deforestation and a dehydrated landscape).

Higher on the slope, Casuarinas have been easier to establish. Here, the ones in the background are being pruned for valuable furniture timber as are a wide range of other farm forestry species, suited to different sites on the property

Pinus radiata are pruned up for better quality timber. They were originally established due to their recognition by the tax man, but the focus has changed over time with the most valuable crop now below the ground, in the form of edible mushrooms such as slippery jack and saffron milk cap.

Here the group observes the understorey of ferns which has established beneath Blackwood and local tea tree. This site was dense with blackberries only 12 years without a tree in site. Seed filled brush mattresses of Leptospermum and mud encapsulated seed balls of Acacia were the main reveg techniques used.

Due to the repair of the main creek, the floodplain has rehydrated. These flats have been excavated to tap into the groundwater, creating a mosaic of water and earth, rich in biodiversity in some places…….

……..and planted out to useful agricultural crops in other places such as cricket bat timber or it would be perfect for ducks, fruit and veg if someone wishes to start an enterprise.

Fodder trees are grown in the hydrated landscape, the leaves and bark of which are devoured by goats and sheep. The left over woody biomass can either become material for building erosion-repairing fascines, or innoculated with saprophytic edible mushrooms like shitake.

A number of methods are used for establishing pole plantings while stock are in the paddock such as these tech-screwed tyres.

Wire mesh can also be used to protect trees from ringbarking

One of the Marshall’s most valuable and successful crops is the black truffle. This is a new orchard which has been established this season, using locally adapted oaks with excellent form for light penetration, and innoculated from a portion of their own truffle stock which they put aside this season.

These oaks were a pleasure to plant into the well prepared bed. This site was like concrete when Peter and Kate first purchased it, but after successive rips with the Keyline plough and a series of green manures, you couldn’t ask for a better start to life if you were a tap-rooted tree.

A number of stands of monopodial bamboos have been established for a variety of uses across the property including soil stabilisation, building material, fodder, biochar production and garden stakes which is an enterprise their daughter Rita runs.

What was once a bare walled gully is now a stabilised chain of ponds

This large world class wetland was created on another one of the hydrated flats, which now has black swans nesting. This particular piece of extensive work seems very altruistic, which it is based on the desire to reverse some of the degradation caused by each of Peter and Kate’s families over the generations, but this area of beautiful wetland habitat also offers significant hydration benefits to the surrounding landscape, with groundwater essentially backing up the slopes.

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Article and images Copyright Cam Wilson, Earth Integral, 2012

When erosion control work is carried out with floodplain rehydration in mind, a more sustained creek flow at the base of the property is one of the most common outcomes. Yet, of all the water harvesting and hydration concepts I’ve discussed with people, this remains the one which draws the most skepticism.

The following diagrams illustrate the way this process works:

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This is a fairly typical erosion gully in the Southern Tablelands. The major erosion happened decades ago, therefore the floor of the gully has mostly revegetated and stabilised. However, the alluvial aquifer remains drained down to approximately the base of the gully.

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With the gully incised, in many locations even the largest runoff events remain contained within the channel. For the short period the creek is running high, there is some lateral infiltration into the alluvial aquifer, but it’s often a fairly insignificant amount.

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Depending on the order of the stream, porous structures (or leaky weirs) of varying heights and types can be constructed (ie vegetated earth-banks, rock gabions, log sills, fascines, brush mattresses etc).

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Whenever there is sufficient flow from above, the structure causes a pool to form. As well as enabling riparian and wetland vegetation to establish with the associated bed stability and habitat benefits, the raised water level in the pool encourages water to laterally rehydrate the surrounding floodplain.

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When flood flows occur, depending on the height of the structure, access to the floodplain is now available once again. With the water spread in a thin sheet across the land, it not only reduces the energy and erosive potential within the channel, but also gives more opportunity for the alluvial aquifer to recharge, with infiltration from above.

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In time, depending largely on how porous the floodplain sediment is, the alluvial aquifer will be raised. (The closer to the surface the water table, the more important the flooding process becomes, due to the freshwater lens it creates over the heavier saline groundwater.)

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Due to porous nature of the structures and floodplain sediments, during extended periods without flow coming into the system, the pools can begin to drop. At such time, water stored in the floodplain begins to feed back into the creek, providing an extended base flow, potentially creating a perennial flow.

At the same time, depending on how high the water table has been raised, floodplain vegetation will benefit from moisture available through capillary action. Deep rooted perennial grasses and riparian trees such as Casuarina and Populus will benefit sooner of course, and provide construction material for further channel repair.

Disclaimer: Where water flow is concerned there are substantial risks involved. While the information and images we publish are formulated in good faith, with the intention of raising awareness of landscape rehydration processes, the contents do not take into account all the social, environmental and regulatory factors which need to be considered before putting that information into practice.  Accordingly, no person should rely on anything contained within as a substitute for specific professional advice.

Article and Images © Cam Wilson, Earth Integral, 2012