Insh Marshes
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RSPB Insh Marshes 1,000 hectares of Internationally Important Wetland stretching from Kingussie to Kincraig © Cairngormsscotlandbigpicture.com / Connect Owned and managed by the RSPB since the 1970’s Insh Marshes Reserve is one of the least modified floodplains in North-West Europe. It is important for the numerous National and International designations, including a Special Site of Scientific Interest (SSSI) and Special Area of Conservation (SAC). Designations highlight and protect aspects such as the wetland habitats of the floodplain, the aspen stand, rare insects, birds and mammals. Insh Marshes is Successfully Hen harriers one of only 2 breeding use the UK sites where Ospreys Marsh to the Nationally producing 53 roost in Rare plant young since Autumn & String Sedge 1992, when Winter Eagle’s claw Found on only 8 can be found. Ospreys first A reliable nested here lichen breeding site sites in the Important site Found in only for curlew, Highlands the for breeding 4 sites in nationally Aspen hoverfly’s and over- life cycle relies Scotland it declined by wintering ducks on aspen trees favours © RSPB© 75% since unpolluted 1990’s on Insh Marshes All photos areas Our Vision Our long term vision is to transform Insh Marshes into a prime example of a naturally functioning floodplain and river system. The river and floodplain will be more connected, tributaries unrestricted by historical modifications and relic ditch systems will no longer have a negative impact on protected wetland habitats. These changes will increase the resilience of local communities and the natural riches of Insh Marshes against climate change, while keeping management requirements sustainable. © RSPB© What is a floodplain? A floodplain is a large, flat expanse of land that forms on either side of a river, stretching to the valley edges. Created over thousands of years as the river meanders back and forth across the valley floor. They are dynamic natural systems and provide a range of benefits to the ecosystems and communities that surround them. 11th Jan 2019 8:40am - high water in the River Spey Wide floodplain Meanders It is up to 1.5km across on These bends mean the river should snake Insh Marshes across the floodplain, slowing river flow © Cairngorms Connect 12th Jan 2019 8:30am - Water breaches embankments & covers floodplain © Cairngorms Connect 13th Jan 2019 8:25am - water drains off floodplain into river © Cairngormsscotlandbigpicture.com / Connect © Cairngorms Connect The River Spey’s sinuosity (bends and curves) and meander migration means that the Insh Marshes floodplain extends extensively across the valley floor. When the river exceeds its capacity and water extends over the floodplain, alluvium, or silts from the river, are deposited over the area. This alluvium is very rich in nutrients and fertilises the land, resulting in these areas traditionally being used for agriculture. Benefits of a floodplain Floodplains provide flood risk reduction benefits by slowing runoff and storing flood water. They reduce flood peaks, velocities and potential for erosion © Cairngorms Connect At its capacity Insh Marshes Underground water sources (or In the absence of this floodplain, it is can hold 35 million cubic aquifers) that serve as our estimated that Aviemore would require metres of water. That’s the primary water source are 7km of flood defences costing same as 1400 Olympic replenished by slow seepage £1.7million Source “Insh Marshes - It’s hydrology, multiple uses & swimming pools! through the floodplain economic value (updated 2007)” Insh Marshes acts as a giant The marshes are crucial for A floodplain filters water, removing natural sponge, holding moderating the effects of excess sediment and nutrients, which water and allowing it to slowly spates from the upper degrade water quality and can dissipate back into the river catchment, slowing down the increase treatment costs. system flow of water and alleviating pressures on areas downstream. Mans influence on the Marshes Although it is cited as one of the least modified floodplains in North-West Europe, it is not a fully naturally functioning floodplain. This is because it has a historic system of management that attempted to drain the land for agriculture dating back to the late 1700s. Embankments Extensive internal drainage system Try to keep the water to the channel and reduces connectivity with the floodplain. In high water Try to drain water out of the floodplain quicker these over top and water is trapped on the than would naturally happen making areas drier floodplain for longer. than they should be. There are approx. 20km of these embankments. © RSPB© Bank protection works alongside the river Spey Prevents the natural meandering of the channel. Attempting to keep the channel to its position. Straightened channel In places the river was straightened; Photo of bank protection to alleviate flooding but making water flow faster in these sections. © RSPB© © Cairngormsscotlandbigpicture.com / Connect These modifications were never fully successful, mainly due to the dynamic nature of the floodplain. With population decreases from the 1800s onwards they quickly fell into disrepair and once heavy machinery was introduced in the early 20th century, communities became unable to tame the marshes, being restricted to the edges for hay crops and grazing. Why are the embankments an issue? With the embankments that run alongside the River Spey and the drainage ditches that are present in some of the surrounding land, the floodplain is not able to function in a natural way. Natural Floodplain Floodplain with Embankments Natural levees created by Embankments higher than deposited sediment from natural levees created from previous floods material found on the floodplain During higher flows, water will During higher flows, water is spread over the floodplain contained in channel, increasing the capacity of increasing flow and erosion in river system places Water can recede back into As levels rise the channel can the channel from the not contain the flow so the floodplain slowly water overtops embankments and is trapped behind them. Capacity for the floodplain to hold water is then reduced Historical modifications have reduced the connectivity of the river channel to the wider floodplain, while the ditches try and move water out of the floodplain more quickly than would naturally happen. This has created an artificial system that we are struggling to manage. History of Insh Marshes Situated in Badenoch meaning “Drowned Land” in the Cairngorms, this area has long been associated with flooding and people. Iron Age 13th Century 13th - early 18th Century Evidence of Post-medieval Farming was of vertical settlements near township of Ruthven alignment - from river to Lynchat. Raitts Cave, surrounding the distant mountains. a souterrain Castle. Area was a Riverside for hay meadows (underground thriving community, & winter pasture chamber) dated long before Kingussie Shoulders of hills for between 550 BC - developed. summer sheilings - where 560AD *Land usage was women & children would small scale - for graze animals self-sufficiency Rent paid as produce Blaeu Map of Scotland 1654 Reproduced with the permission of the National Library of Scotland 14th - 19th Century Early 18th Century Late 18th Century Badenoch was a hub for After 1715 Jacobite Two prominent cattle drovers bringing rebellion, Ruthven landowners John Dow & cattle from north and west, Barracks was built to quash Hugh Tod commission heading for markets in the any further rebellions. building embankments Borders & England. After the Battle of Culloden along the Spey to restrict Union Act 1707 increased in 1746, clan systems flooding & allow areas to demand in England. break down, chiefs become stay drier for longer - Many thousands of cattle landowners and move increased value of passed through tenants (forcibly in some pastures twenty-fold Badenoch, using pastures cases) off the land to make to graze before heading way for profitable sheep south Jelfe, Andrews (Architect) draught for Ruthven Barracks 1719 Reproduced with the permission of the National Library of Scotland History of Insh Marshes Late 18th Century Late 18th Century cont.. Late 18th Century cont.. Estate owner Captain John cont.. ‘Improvements’ at MacPherson employed a Straightening of Spey Pitmain by John Maclean stone mason to construct - removal of one loop, transformed 200ha of embankments ‘with three Loupouchkie, which “land deemed no better roes of fail (turf) and six previously had slowed than a swamp” to “firm quarter high of stone’ to the water flow in the land bearing good crops protect hay meadows. river. of hay & corn”. Level of Loch Insh In addition, an lowered by 6 feet by impressive 1000 sheep digging a canal to sustained by this land drain water back into Bartholomew’s Half Inch to the Mile Map 1902 the River Spey Reproduced with the permission of the National Library of Scotland © RSPB© 19th & 20th Century 20th Century 1973 Queen Victoria’s visit Modern farming RSPB Scotland raised popularity - machinery (tractors etc) acquire land on Insh wealthy bought grouse too heavy to be used in marshes. Land is shoots depriving tenants wet areas. This results managed to ensure of hill grazing. in fewer areas being habitats of National & European importance Clearances and World used for agriculture, are in favourable Wars decreased with land reverting back condition. population - few left to to marsh and being left maintain the agricultural to nature. land. Land Utilisation Survey