Beverley Brook Partnership
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BEVERLEY BROOK PARTNERSHIP Working together since 2013, the Beverley Brook Catchment Partnership aims to improve, restore and protect the health of the Beverley Brook and its catchment for both local wildlife and local communities. THE RIVER Starting in Worcester Park, the Beverley Brook travels north passing through key green spaces such as Richmond Park and Wimbledon Common and joining the Thames in Barnes. “Our vision is for the Beverley Brook to be a clean river, rich in biodiversity, that is a resource for an engaged local community” Explore this Catchment Plan to find out more about the Beverley Brook: its history, the issues it faces and what the Partnership is doing to restore and protect the Beverley Brook. THE BEVERLEY BROOK “Beverley Brook comes from Beaver’s Ley, which means place where Beavers rest” Was the Brook named after beavers which once inhabited the river? KEY INFORMATION LAND COVER Length 14.3km Tributaries Pyl Brook and East Pyl Catchment Area 64 km2 Type Heavily Modified Population 880,000 The Beverley Brook rises in Worcester Park and travels 14 km to Richmond where it joins the River Thames at Barn Elms. The Brook passes through Richmond Park, Wimbledon Common and the London Wetland Centre, all of which are Sites of Special Scientific Interest (SSSIs) and key green spaces in south London. Historically, the Beverley Brook rose from minor springs along the edge of the North Downs, but with increases in ground-water Based upon LCM2015 © NERC (CEH) 2017 abstraction, these springs no longer exist Improved and now the Brook is entirely Woodland grassland disconnected from the Freshwater chalk aquifer. Heather grassland Suburban Today, the flow of the Arable and Beverley Brook is Urban Horticulture maintained by treated effluent from the GEOLOGYGEOLOGY Hogsmill Sewage Thanet Sand White Chalk Treatment Works and surface water runoff Lambeth Clay Thames Clay from the surrounding River Terrace Deposits catchment. Alluvium Sand and gravel © British Geological Survey (BGS) Beverley Brook Catchment Plan 2020 2 THE BEVERLEY BROOK A HEAVILY MODIFIED RIVER The Brook was altered and changed throughout the 20th century to make room for development and in the name of flood risk. The main channel was straightened, widened and Richmond Park deepened; disconnected from its floodplain with concrete banks and wooden toe boarding. These modifications have left a bare, uniform channel with few places for fish and other wildlife to seek refuge from the high, flashy flows and intermittent pollution events. Wimbledon Common THE WATER FRAMEWORK DIRECTIVE (WFD) The WFD is a legislative framework designed to protect and improve the quality of all water resources within the UK and the European Union. To monitor, progress and drive improvement, individual chemical and biological elements are assessed and classified as High, Good, Moderate, Poor and Bad; with the aim of bringing all waterbodies up to Good status. WFD Status: Moderate Ecological Status For the purpose of the Water Framework Heavily Modified Waterbody Directive, the Beverley Brook is classified Ecological Status Cycle 2 as a Heavily Modified Waterbody, Fish Macrophytes having been substantially changed in character by human physical Invertebrates Phytobenthos modifications. The target is therefore for Physico-chemical Status Cycle 2 the Beverley Brook to reach Good Ecological Potential (GEP) and not Good Phosphate Dissolved Oxygen Ecological Status (GES). Ammonium pH The Beverley Brook is currently considered to be of Moderate Ecological Potential, with phosphate concentrations being the limiting factor. However, the data highlights that all biological elements are classified as below good status, with fish populations of particular concern for the river, classified as bad. It is important to note that WFD classifications are not always a true representation of the reality, often based on limited sample sites with few repetitions. Considering local knowledge and other evidence is therefore key in understanding the catchment. Beverley Brook Catchment Plan 2020 3 THE BEVERLEY BROOK KEY ISSUES FOR THE BEVERLEY BROOK 1. WATER QUANTITY At times, a significant proportion of the base flow of the Beverley Brook comes from the Hogsmill Sewage Treatment Works, in the form of treated effluent. While this can safeguard against low flows in the summer, it can also make the river highly vulnerable to fluctuations in the quantity and quality of the water from this source. The remainder of the flow comes from urban surface water run-off. With the increased paving and development of the catchment, surface water now reaches the Brook much faster, with little infiltration into the ground. This has made the Brook flashy in nature, with sudden high peaks in flow. This is further exacerbated by the heavily modified channel which has been altered and changed through the 20th century including straightening, widening and deepening. These modifications have left a bare, uniform channel with few places for fish and other wildlife to seek refuge from the high flows which can wash out fish and other wildlife. 2. WATER QUALITY Urban Road Run-Off A large proportion of the Brook’s flow comes from surface water, which in an urban environment also brings poor water quality, with heavy metals and other contaminants such as oil (pictured left) washing into the Brook from London’s roads. Phosphate The river is failing for phosphate under the WFD classification. High phosphate levels can increase plant growth, including algae, which if left unchecked can cause eutrophication of the water. The primary source of phosphate is the treated effluent from the Hogsmill Sewage Treatment Works which is pumped into the Beverley Brook to maintain flows. Although the Hogsmill STW systems has systems installed to remove phosphate (P-stripping), the process is still unable to reduce concentrations to an acceptable level for a natural river environment. Misconnections & Combined Sewer Outfalls There is strong evidence that there are other sources of ammonia and phosphate entering the Beverley Brook, aside from the Hogsmill STW effluent, most likely from misconnected properties (waste water from household appliances being discharged directly into the river by incorrect plumbing) and CSOs. Beverley Brook Catchment Plan 2020 4 THE BEVERLEY BROOK KEY ISSUES FOR THE BEVERLEY BROOK 3. HABITATS FOR FISH & INVERTEBRATES Fish require a number of different habitats to complete their life cycles including spawning grounds, fry refuges, habitats to hunt, refuge from predators and over-wintering areas. With a straight, featureless channel, there are few of these habitat features available to fish in the Beverley Brook (pictured right). The lack of backwaters, side channels and refuges leave fish with nowhere to escape during the high, flashy flows of the Brook. Sedimentation is also a key issue for the river. Modifications, such as the deepening and widening of the channel, have decreased the power of the flow in the Brook which has increased silt and sand deposition (pictured below), smothering the natural river bed. In Richmond Park, over grazing from deer increases bank erosion and silt inputs. Although stocked fish thrive in isolated reaches of the Brook, natural recruitment is poor. This highlights the specific lack of suitable spawning gravels and juvenile fry habitats. High phosphate levels encourage the growth of algae, hindering the establishment of more desirable aquatic vegetation. Large sections of the brook are also over-shaded, further inhibiting macrophyte growth that would provide valuable cover for fish and invertebrates. Any aquatic plants that do establish are likely to be washed away downstream during flashy flows. Beverley Brook Catchment Plan 2020 5 THE BEVERLEY BROOK AN ACTION PLAN FOR THE BEVERLEY BROOK The Catchment Partnership has identified some priority Aims and Objectives, linked to the key issues for the Beverley Brook. These Aims and Objectives have been used to develop actions which describe how the Partnership will work together to deliver improvements to the river. AIMS OBJECTIVES Assess the species, habitats and features along the HABITATS AND BIODIVERSITY Beverley Brook, identifying areas for enhancement or improved connectivity Habitats along the Beverley Brook are Deliver projects to enhance and restore habitats along varied, plentiful and healthy. The river the Beverley Brook corridor can support its key flagship species. Identify and remove invasive non-native species (INNS) along the Beverley Brook Remove litter and plastic pollution from the river Urban diffuse pollution is addressed, or mitigated for, WATER QUALITY across the catchment The Beverley Brook has clean water, that is Phosphate inputs are reduced resilient to change and protected by landowners and the local community. Water quality monitoring across the catchment is improved or enhanced Improve understanding of the flow regime through the WATER MANAGEMENT catchment Identify areas for practical projects to improve flow diversity and variation The Beverley Brook has a more natural Deliver habitat restoration projects that naturalise flow regime which is resilient to future flow along the river pressures. Reduce flood risk and the flashy nature of river Abstractions and recirculation systems are more resilient and reliable Raise the profile of the Beverley Brook and improve COMMUNITY ENGAGEMENT public understanding of the Catchment Partnership Provide opportunities for the public to engage with the People value the Beverley Brook