Amanda Tisdall S1208746
DRAFT RESERVE MANAGEMENT PLAN 2013_
Castle Meads/Alney Island Nature Reserve
This document is a management plan for the Castle Meads and Alney Island Nature Reserve and Visitor Interpretation Centre. It provides direction for the future development, management and use of this open space area.
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CONTENTS Part 1-Background and Context 1.1 Introduction 1.2 Definition of a management plan 1.3 Statutory requirements 1.4 Objective of this management plan
Part 2-Reserve Values 2.1 Recreation and use 2.2 Access, Parking and Circulation 2.3 Administration and management
Part 3- Management Objectives and policies 3.1 Cultural Heritage 3.2 Community 3.3 Heritage Values 3.4 Landscape 3.5 Natural Values 3.6 Administration and management 3.7 Visual and Amenity values 3.8 Unstructured recreation Use 3.9 Organised Events and Commercial Use 3.10 Design and Amenity Standards
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Part 4 – Habitat Management Zones 4.1 Landscape Habitat Maintenance and management 4.2 Landform Grass 4.3 Landform Wild-Flowers 4.4 Spiled Willows 4.5 Pollarded Willows 4.6 Rain Gardens 4.7 Bio-Filtration Swales 4.8 Living Roof 4.9 Bio-Retention Tree Pits 4.10 Wetland 4.11 Habitat Management Document
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Part 5 – Vegetation Plan
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11 12 13 14
The Format of this Plan This plan is organised into the following chapters: Part 1. Background and Context Part one is an overview which explains the legal requirement for preparing the plan, its purpose, and the process of preparing the plan. It provides a summary of the future management for Castle Meads Alney Island Nature Reserve.. Part 2 - Reserve Values Part two outlines the reserves existing values, including access and use Part 3 - Management Objectives and Policies This part provides a suite of management objectives and policies, grouped into areas of management focus. These are the rules for the reserve, which are tied back to the major management goals which are in turn underpinned by the Reserves Act 1977 classifications, and community aspirations. Part 4 - Habitat Management Zones Part four discusses the key habitats and the required management and maintenance processes for each as part of the vegetation plan for the visitor interpretation centre. Part 5 - Vegetation Plan Part 5 is a vegetation plan for the Castle Meads Alney Island Nature Reserve visitor interpretation centre.
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Part 1 – Background and Context 1.1 Introduction Castle Meads and Alney Island Nature Reserve Visitor Interpretation Centre is located on the western side of the A430 bypass (Castle Meads Way) and South West of Gloucester city. It has a car park located West of the Visitor Interpretation Centre adjacent to the A430 bypass. Castle Meads and Alney Island Nature Reserve contains significant history and ecological value, and is highly valued by the local community. The council is not required to do a management plan for this reserve, but it is useful for the needs and interests of the community.
1.2 Definition and purpose of a management plan The Reserves Act 1977 requires the council to prepare reserve management plans for nearly all parks classified as ‘reserves’ under council control. Reserve management plans outline the Council’s general intentions for the use, development, maintenance, protection and preservation of its reserves through a series of objectives and policies. The aim of this is to ensure that park development and enjoyment are based on sound principles and that, through involvement, the needs of the public are clearly identified. The Reserves Act 1977 outlines a formal procedure for public involvement in this planning process. The purpose of this plan, therefore, is to provide for the use, enjoyment, maintenance, protection and development of the reserve, in keeping with the existing character of the area and within the limits of the Council’s resources.
1.3 Statutory requirements The intention of the Reserve management plan is to: Reserves Act 1977 “Provide for and ensure the use, enjoyment, protection and preservation, as the case may require, and to the extent that the administering body’s resources permit, the development, as appropriate, of the reserve for the purposes for which it was classified.” Once accepted, the plan is to be subject to continuous review to adapt to changing circumstances or increased knowledge. The purpose of a Reserve management plan: A reserve management plan provides a structure for carrying out future management in an integrated way through a series of objectives and policies. Additionally, there are often concept plans developed for the reserves, which recognize particular areas of work, which can be
prioritised over a number of years. Each management plan aims to balance the protection of natural resources, but also providing appropriate recreational opportunities for the local and wider community. Management plans can be prepared for either individual reserves or for a group of similar reserves.
1.4 Objective of this management plan This management plan has been prepared in order to provide responsible management of the natural, landscape and recreational values of Castle Meads and Alney Island Nature Reserve for community benefit and enjoyment.
Part 2 - Reserve Values 2.1 Recreation and use Castle Meads and Alney Island Nature Reserve is principally open space for education and informal passive recreation activities for the local community. The reserve has many pathways that you can walk or jog along and enjoy the vast amount of native flora and fauna. It has many stopping points with seating for people to utilise for their own enjoyment.
2.2 Access, Parking and Circulation Pedestrian access to the reserve is gained through a variety of entrances. At present vehicles can park near the visitor interpretation centre in the newly built car park adjacent to the A430 bypass. There are currently a variety of pathways that run though, and around the reserve, which all lead to the visitor interpretation centre.
2.3 Administration and management At present there is a reserve management plan for Castle Meads and Alney Island Nature Reserve, and is currently managed and maintained by the Gloucester City Council’s Countryside Unit. This management plan needs to be updated due to the recent development of the reserve.
Part 3 - Management Objectives and Policies 3.1 Cultural Heritage Objective 1 To acknowledge and protect cultural heritage values and archaeological sites and objects associated with Castle Meads Alney Island Nature Reserve. Policy 1.1
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Where development works are proposed in relation to known cultural heritage and archaeological sites and objects and archaeologist are to be involved in all phases of the project. Policy 1.2 Any new development/s will be sympathetic to the surroundings, whether tangible or ephemeral in nature. Policy 1.3 Large areas of open space and a pleasant ambience will be protected, for the traditional activities of passive recreation.
3.2 Community Objective 1 To foster community participation in the management of the reserve
3.4 Landscape Objective 1 To protect the landscape features of Castle Meads and Alney Island Nature Reserve which contribute to its high level of naturalness and its value as a representative wetland, grassland and flood alleviation landscape.
Objective 2 To protect important views of Gloucester city Objective 3 To retain an informal landscape character and open spatial quality to the reserve. Policies 1.1 Built developments will only be permitted where these are sympathetic to the key elements, features and patterns which contribute positively to landscape quality.
Policy 1.1 Participation of local community in the care of the reserve through volunteer programmes will be encouraged.
Policies 1.2 Establish a mosaic of tree stands and open areas in a naturalised pattern to provide contrasting areas of shade and openness. Tree and plant groupings are to be located judiciously in accordance with design set down in an overall planting master plan;
Policy 1.2 The development of facilities which benefit and remain accessible to the local community will
Policies 1.3 Establish a native vegetation palette relevant to the existing ecotones
be prioritised.
3.3 Heritage Values
Policies 1.4 Boundary treatments shall contribute to the coherent wetland character of the reserve, and shall not be visually intrusive or detracting.
Objective 1 To provide for the conservation of the historically significant aspects of retained vegetation within Castle Meads and Alney Island Nature Reserve.
3.5 Natural Values
Policy 1.2 Establish and maintain a complete inventory of trees within the reserve.
Wetland and flood processes create a dynamic environment at Castle Meads and Alney Island Nature Reserve. This management plan focuses on protecting the ability of these natural processes and biodiversity to endure, while ensuring the amenity of the wetland for public use and enjoyment is maintained and enhanced.
Policy 1.3 Undertake a complete assessment of all significant trees in the reserve including research into their age and source, their current state of health and life expectancy.
Objective 1 To protect the biological values of Castle Meads and Alney Island Nature Reserve. Objective 2 To protect the interrelationship between the reserve and the River Severn.
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Objective 3 To enable wetland processes to take place while protecting the recreational amenity of the reserve. Objective 4 To enhance the contribution the reserve makes to the local biodiversity Policy 1.1 Stormwater discharge will be managed through the range of intervention identified in the Castle Meads and Alney Island Catchment Management Plan aimed at improving water quality, recreation amenity and the attractiveness of the wetland. All unsightly outfall structures will be progressively removed and replaced with soft and sympathetic engineering solutions.
3.6 Administration and management Objective 1 To ensure that all management decisions are made in accordance with the primary purpose of the reserve, and in accordance with the objectives and policies of this plan Objective 2 To ensure that the reserve management plan is kept under continuous review, and amended in a timely manner. Objective 3 To ensure the park is managed in terms of its reserve classification for the enjoyment and use of the public, now and in the future.
Policy 1.2 New built structures are to take account of predicted flood level rise and increased inundation levels.
Policy 1.1 To recognise the management demand which arises from the vulnerability of the reserve being on the urban fringe of Gloucester, and potential for flooding.
Policy 1.3 Native biodiversity and ecosystem services will be enhanced through the establishment and enhancement of wetland habitats in association with stormwater upgrades and other developments on the reserve.
Policy 1.2 To maintain the area as a public open space for education and both passive and active recreational uses for the benefit of the local community.
Policy 1.5 All invasive plant species be removed Policy 1.6 Establish and maintain a regular programme of inspection and maintenance works by experienced arborists for all trees in the reserve.
3.7 Visual and Amenity values Objective 1 To maintain the visual character of the reserve.
Policy 1.7 Consider the replacement, over time, of more recent out of place planting within the reserve with species more appropriate to the heritage significance of the reserve.
Explanation The Reserves overall character is primarily from the views/vistas and variety of habitats that the vegetation provides. Regular maintenance and management of the vegetation is crucial to the success of the reserve.
Policy 1.8 All by-laws relating to the protection of the wetlands natural environment and that of the adjoining wet woodland and grassland environment shall be strictly enforced.
Policy 1.1 Regular maintenance of vegetation as per the landscape maintenance and management document. Objective 2 To co-ordinate and integrate all planting undertaken within the reserve. Explanation It is important that all planting, whether for screening or amenity purposes or for the enhancement of natural values, be coordinated and carefully planned. This will optimise the success of such plantings.
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Policy 2.1 Planting plans will be prepared for all areas of the reserve which are scheduled for amenity and/or screening plantings or for re-vegetation.
Objective 1 To allow for the occupation of the reserve for organised events and commercial activities compatible with the designated purpose of the reserve area.
3.8 Unstructured Recreation Use
Objective 2 To ensure that organised events and commercial activities do not unreasonably limit access, or impact negatively on the important values of the reserve.
This plan seeks to protect the function of the reserve for public use and enjoyment. Such freedom of access is subject to a range of restrictions aimed at protecting the reserves important values and the enjoyment of other users. Objective 1 To retain a high level of unrestricted access throughout the reserve to other adjoining walkways Objective 2 To facilitate a wide range of recreation activities for general public use. Policy 1.1 Unimpeded public access will be provided to the reserve except where: • It is deemed necessary to restrict access for the protection of cultural heritage, biological landscape and environmental values and for the stability of the land; • The safety of the reserve users is at risk; • All users of the reserve shall be responsible for ensuring that their use complies with council by-laws;
Policy 1.1 Temporary events and commercial activities will be granted through the Gloucester City Council. Policy 1.2 An events management plan for Castle Meads Alney Island Nature Reserve which identifies the following key information will be prepared; • The sustainable level of impact from activities on the physical environment; • The range of events suitable for the reserves environment • Application procedures for event organisers; • Re-mediation to original condition at the conclusion of the event; • Protection of access for the general public; • Public safety; • Management of any adverse effects; • Provision for temporary built structures; • Temporary closure and public notification procedures; Policy 1.3 Events which benefit the local community will be prioritised;
3.9 Organised Events and Commercial Activities The reserve is a venue for people to participate in organised events. These events are temporary and do not give any rights beyond the period of the event. The activities contribute significantly to the vibrancy of the reserve. However with the development of Castle Meads Alney Island nature Reserve this will put greater pressure on the natural resources of the reserve, amenity and general public access. This plan seeks to provide for increased events while managing any adverse effects on the reserve, environment, and other reserve users.
Policy 1.4 The Castle Meads grassland on the Eastern side of the bypass is identified as the main events activity zone within the reserve. Policy 1.5 Any events which would negatively impact the enjoyment of the reserve by other users for a sustained period of time are prohibited; Policy 1.6 Events will be kept away from biologically significant areas of the reserve to reduce negative impacts. Policy 1.7 Temporary installation of structures for events will be permitted subject to council policy and resource consent requirements.
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3.10 Design and Amenity Standards This reserve management plan provides a policy framework for protection, use and development of Castle Meads Alney Island Nature Reserve. It does not identify specific design. Objective 1 To create fitting design standards for Castle Meads Alney Island Nature Reserve which acknowledge and reinforce its outstanding landscape quality. Objective 2 To integrate design and design standards along the Quay Side to adjoining spaces in the reserve. Policy 1 The following design principles will underpin all design decisions for the reserve: Design with Place: • Design to respond to and reinforce wetland character; • Cultural heritage - make visible and express past histories; • Design in sympathy with the space - in scale, colour, form, rhythm. Design with Nature: • Protect and reinforce natural character; • Integrate with the coastal character, in scale and materiality • Choose local materials • Reinforce native biodiversity • Make natural processes visible Design with Prudency • Collaborate - Involve the community and artists etc.; • Consider all of the life cycle - reuse, recycle; • Design for durability • Make cost effective choices
Part 4 - Habitat Management Zones 4.1 Landscape Habitat Maintenance and Management Castle Meads Alney Island Nature Reserve possesses a number of distinct habitats characterised by their physical qualities. This plan identifies a management focus for each of these habitats. Compatible activities will be clustered together, intensifying and further reinforcing the purpose of each part of the reserve. The effect will be that the reserve takes on
a more constructed character in certain areas, while the majority of the reserve will retain its informal character. A development plan, which sits alongside this management plan, deals in more detail with the design of spaces. Objective 1 To identify habitats within the reserve and reinforce their distinct character and purpose. Objective 2 To ensure that the reserve retains an overall unstructured and natural character. Objective 3 To optimise recreation opportunities for both structured and unstructured activities in balance with each other. Policy 1.1 Plant Establishment: • After-care / Establishment (Defects liability period) is a crucial part of the design/ build process. The designer / landscape architect oversees the work of the contractor on behalf of the client, maintaining quality and standard of work and preventing plant or hard material failure. • Shrubs, herbaceous perennials, climbers, grasses Including turf etc. are covered by a period of between 6-12mths. Trees usually require 18mths (dormancy period 6 -12mths). Ironically the establishment of plants on most sites usually takes between 3-5 growing seasons. Plants fail because: • Poor site preparation - soil compaction, poor drainage, pollutants, • Inappropriate plant selection – lack of understanding of soil, micro-climates, aspect, location, context • Poor plant supply– designer or contractors inability to specify correct quality. Root desiccation, poor storage, Wrong season! • Poor planting techniques – timing, hole size, incorrect depth, lack of stake, container not removed, • Post planting/After-care - lack of water, no moisture conservation, vandalism / theft, competition, damage, Policy 1.2 Designers responsibilities: • Design – understanding of site, context, drawings, specification, site supervision, contractor suitability, nursery suitability, • Preparation– plant supply, plant handling, storage, soil prep, waste removal, deep ripping, aeration, rotavating soil tilth, removal of detritus, weed removal, recommended top soil,
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fertilisers, organic ameliorations (approved chemicals), arboricultural work, checking ground. • Implementation – approved contractor / sub contractor, method of planting, excavation of holes / tree pits, deep ripping, fertilisers, soil ameliorants, mulches, mulch mats, stakes, watering in, tree irrigation, guards / fences, • Establishment – regular maintenance, weed removal, watering trees during warm weather, spraying, rodent control, checking stakes & ties, pest & disease removal, pruning, replacement of failed vegetation.
4.2 Landform Grass: Laying of turf - Newly laid turf must be sprayed regularly over the first summer. Cutting - The landform lawn must be cut on a regular basis using a Cylinder mower to maintain the desired effect. The lawn must be close mown sward to 30mm. The first cutting of newly laid turf can only happen when the roots have grown into the soil when at least two thirds of the turf cannot be easily pulled up. Cuttings must be removed. Controlling weeds in the lawn - Most weeds that grow in lawns can be successfully controlled using a systematic “hormone” herbicide. If the weed infestation is not too extensive, it is best to fork them out by hand. Weed killers are to be applied twice a year during autumn and spring. Moss control - Lawns offer the perfect environment for some mosses, many of which can become a serious problem and stifle grass to extinction. Moss killers are to be applied twice a year during autumn and spring. Scarifying the lawn - This is to be carried out in late spring. Moss often develops in the very early spring, so the most fruitful time to carry out scarifying is in the late spring. Only scarify a lawn if there is a good scattering of grass throughout the moss. Once the moss has been removed and some fertiliser applied, the grass should soon spread and thicken up. Top dressing and feeding - A well-sieved mixture of loam, peat and sharp sand, often mixed with some fertilizer and sometime grass seed can be used to fill in low spots, small, denuded patches made when treating the lawn for moss. This should be applied during the spring, summer and autumn as this is the time the lawn will best respond.
4.3 Landform Wild-flowers Management of a new meadow: Cutting - When the seeds have germinated and the grasses reach a height of about 10cm,
the meadow should be cut. This will knock back unwanted ‘weeds’ such as groundsel and chickweed. Any thistles and docks should be pulled up. Before cutting, you can lightly roll the meadow to firm any plants into the soil. During the first year try to cut your meadow every 6-8-weeks. Always remove the cuttings to prevent a build up of dead plant material. This will help the meadow plants to become established. In following years, adopt a twice a year mowing pattern. Cutting - It is best done twice a year at the following times. Once in autumn (late August to September), once in early spring (late March to early April). The cuttings must be removed. This will make sure that the wild-flowers can grow. It will also prevent thistles, docks, brambles and scrub from taking over. The autumn cut gives the meadow plants the best chance to flower and set seed. Cutting can be carried out with a variety of tools. A power strimmer or hay flail can be used.
4.4 Spilled Willows Willow spilling is a traditional soft engineering technique used to stabilise banks. It consists of weaving live willow rods between live willow stakes set into the affected bank at regular intervals. The space behind the willow wall to the existing bank is then filled with soil to provide an area for the willow roots to grow. Osier willow is considered to be the most appropriate species to provide poles, due to its pliable nature and the fact that it is an indigenous species. Alternatively, commercially available alternatives could be used, but these will require more vertical support posts. Spilling - Willow spilling is normally carried out between November and April during the harvesting of the willow (dependent upon the season) and should be installed within three weeks of harvest. Cutting - Spilling requires maintenance to control top growth this is cut in the winter months between November and April or as per needed if the willows grow to high.
4.5 Pollarded Willows Pollarding - Pollarding a tree usually done annually, and would needs to be carried out every few years to avoid potential problems once the tree is well established. The best time for pollarding is in late winter or early spring. Between February and April. • Branches should be pruned just above the previous pollarding cuts • In some cases, such as where some leaf cover is required, leave some branches intact or cut back to a side branch Pollarding young Willows Once the young trees have reached the desired height, you can begin to pollard them. Leave a trunk supporting three or five branches – these branches are cut back to a desirable
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length and the twiggy growth appears at these ends. Once the tree is pollarded, continue the annual cycle of cutting.
4.6 Rain Gardens Irrigation - New plants need to be watered regularly for the first year until their roots are established, even though the rain gardens catch storm water. Weed • Frequent weeding will be necessary in the first few years before plants become established. Remove by hand any weeds, ensuring that the entire plant is removed, including the roots. As the plants in the beds mature, they will in any gaps and suppress weed growth. • During winter, remove any dead or untidy plants. Re-plant - Replace dead plants if and as required, adjusting species mix according to local conditions. Refer to site planting plan and strategy for appropriate vegetation. Mulch - To maintain the bowl-shaped profile and stormwater holding capacity of the rain garden, mulching is not suggested until a few years after the initial installation. Once the rain garden is established, mulch, is not necessary, unless its more formal appearance is preferred. When applying mulch, maintain a 5-10cm layer. Cutting - Cutting the rain garden occasionally will be beneficial. Cutting can be undertaken in late summer or autumn with a scythe or strimmer with particularly tough material cut by hand with secateurs. Remove this cut for composting. Sediment - Remove sediments during summer months when they build up to 6 inches at any spot, cover biofilter vegetation, or otherwise interfere with rain garden operation. Monitor For blue algae as this is a health hazard for humans and dogs. Check inlets/outlets/sediment traps and clear any blockages. Frequency - Monthly and before/after heavy rain/flooding events. Filter Media Surface - Inspect for the accumulation of an impermeable layer (such as oily or clayey sediment) that have formed on the surface of the filter media. A symptom may be that water remains ponded in the tree pit for more than a few hours after a rain event. Repair minor accumulations by raking away any mulch on the surface and scarifying the surface of the filter media between plants. 3 monthly after rain. Rubbish - Check and remove any rubbish and other inorganic debris from the rain gardens regularly.
4.7 Bio-Filtration Swales Irrigation - New plants need to be watered regularly for the first year until their roots are established, even though the Bio-Filtration Swales catch storm water. Cutting - Cut back vegetation at the end of the growing season during the late summer and early autumn months with a scythe or strimmer with particularly tough material cut by hand with secateurs. Remove this cut for composting. When cutting let the plants stand at a height exceeding the design water depth by at least 2 inches at the end of the growing season. Weed • Frequent weeding will be necessary in the first few years before plants become established. Remove by hand any weeds, ensuring that the entire plant is removed, including the roots. As the plants in the beds mature, they will in any gaps and suppress weed growth. • During winter, remove any dead or untidy plants. Re-plant - Replace dead plants if and as required, adjusting species mix according to local conditions. Refer to site planting plan and strategy for appropriate vegetation. Sediment • Remove sediments during summer months when they build up to 6 inches at any spot, cover biofilter vegetation, or otherwise interfere with biofilter operation. • Clean curb cuts when soil and vegetation build up interferes with flow introduction. This should be done every 5-7years Monitor • For blue algae as this is a health hazard for humans and dogs. • Check inlets/outlets/sediment traps and clear any blockages. Frequency - Monthly and before/after heavy rain/flooding events. • Inspect biofilter regularly, especially after periods of heavy runoff. Remove sediments and reseed as necessary. Monthly and occasionally after rain. Rubbish - Remove rubbish and other inorganic debris as required in order to keep biofilters attractive in appearance.
4.8 Living Roof Water - New plants need to be watered regularly after initial installation. As per required after plants have established. Cutting • Undertake clipping, cutting, and coppicing as required. Leave cuttings in situ or create habitat piles. This shall be done at the end of the growing season during the late summer and early autumn months
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• Mow as required and in appropriate conditions, to achieve a varied sward structure. Before mowing check for wildlife. Use clippings to create habitat piles. • Retain dead stems in autumn as habitat for overwintering invertebrates. Re-plant - Replace dead plants if and as required, adjusting species mix according to local conditions. Refer to site planting plan and strategy for appropriate vegetation. Weed Weed as necessary. Every 3 months. Monthly during the summer months. Frequent weeding will be necessary in the first few years before plants become established. Remove by hand any weeds, ensuring that the entire plant is removed, including the roots. Every 3-4 weeks Habitat features - Repair, create new and maintain habitat features (insect hotels, log piles, nest boxes, etc.) as required. Do not remove deadwood. Survey - Undertake regular botanical and faunal surveys. Invertebrate monitoring would be useful in order to determine which species are using the roof. The information gathered can be used to inform future management, and to study how roof design influences biodiversity. Rubbish • Remove rubbish and other inorganic debris as required. • Clear shingle perimeters and drainage layers, removing unwanted vegetation. The filter media for the rain garden must meet certain specifications. It is crucial that the filter media installed maintains its ability to pass water through the media in the long term. The filter media must be correctly installed with an appropriate level of compaction during installation. Filter media must be lightly compacted during installation to prevent migration of fine particles. A single pass on a drum roller should be performed.
4.9 - Bio-Retention Tree Pits Tree establishment - Newly placed trees require that they be staked for support. This period is between 18 to 24 months. Regular maintenance of the trees and stakes are crucial to their success and survival. Once the trees are adequately established the sakes should be removed and the holes filled in with filter media. Failure to fill in the holes will result in the creation of a short circuit pathway. Instead of ponding on the surface of the rain garden, the holes left behind allow water to bypass the filter media and drain directly into the drainage layer at the base of the cell, effectively bypassing any pollutant removal processes.
Inspection - Regular inspection and maintenance should be carried out to ensure the system functions as designed. It is recommended that these checks be undertaken on a three monthly basis during the initial period of operating the system. A less frequent schedule will be determined after the system has been established. Sediment removal - Remove sediment build up from the surface of bio-retention trees. Frequency - 3 monthly after rain. Holes or Scour - Infill any holes in the filter media. Check for erosion or scour and repair. Frequency - 3 monthly after rain. Filter Media Surface - Inspect for the accumulation of an impermeable layer (such as oily or clayey sediment) that have formed on the surface of the filter media. A symptom may be that water remains ponded in the tree pit for more than a few hours after a rain event. Repair minor accumulations by raking away any mulch on the surface and scarifyling the surface of the filter media between plants. Frequency - 3 monthly after rain. Irrigation - Trees will require regular irrigation during the establishment phase. Trees should be irrigated through an Ag pipe Pests and Diseases - Assess plants for disease, pest infection, and stunted growth. Treat or replace as necessary. Reduced plant density reduces pollutant removal and infiltration performance. Frequency - 3 monthly after rain. Re-plant - Replace dead plants if and as required, adjusting species mix according to local conditions. Refer to site planting plan and strategy for appropriate vegetation. Weed • Frequent weeding will be necessary in the first few years before plants become established. Remove by hand any weeds, ensuring that the entire plant is removed, including the roots. As the plants in the beds mature, they will in any gaps and suppress weed growth. • During winter, remove any dead or untidy plants. Frequency - 3 monthly. Perforated Pipe - Ensure that perforated pipes are not blocked to prevent filter media and plants from becoming waterlogged. Frequency - 6 monthly after rain. Monitor For blue algae as this is a health hazard for humans and dogs. Check inlets/outlets/sediment traps and clear any blockages. Frequency - Monthly and before/after heavy rain/flooding events. Rubbish - Check and remove any rubbish and other inorganic debris from the tree pits regularly.
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4.10 - Wetland Regular inspections of the wetland must be undertaken to ensure its proper and continued function. The problems that most frequently occur are blockages of inlets/outlets, flow regulating devices, siltation of storage areas, algal growth and plant die-back. Maintenance operations should include: • Checking inlet and outlet structures. Frequency - Bi annually • Cleaning off surfaces where solids and float able substances have accumulated to an extent that they may block flows. Frequency - Bi annually cleaned when required • Removal of gross litter/solids. Frequency - Bi annually cleaned when required • Checking sediment accumulation levels (wetland, sediment traps, infiltration trenches etc.) Frequency - Annually before winter • Bank erosion. Frequency - Annually • General maintenance of the appearance and status of vegetation and any surrounding landscaped zones. Frequency - Annually Cleaning sediment traps, removal of sediment Sediments will require removal from settlement trenches, ponds if present. Sediment is likely to be classified as hazardous waste and may require de-watering on site prior to disposal at a licensed waste facility. Annually maintenance inspections will assess whether sediment removal is necessary. Inspection following major storms, and flooding events will be required to assess whether litter and gross solids have been introduced and need removing. Generally sediment removal will not be required before 10-15 years. Maintenance of the substrate and plants Maintenance of wetlands involve ensuring continued hydraulic conductivity of the substrate, removal of accumulated sludge’s in the settlement pond and inlet area of the wetland, removal of decaying algae and macrophytes in the settlement trenches, and replacement of any vegetation if required. Frequency - Annually
cutting to meet individual site requirements. The cut reed beds are to be raked into habitat piles that benefit the invertebrates. When cutting reed beds you should cut the beds in small patches, avoiding very wet or unstable parts, ensure that some tall vegetation is left standing to provide habitat continuity for associated flora and fauna. All cutting and mowing techniques are to cut the reed beds to a uniform height reducing variability within the vegetation, which in turn, can result in loss of associated flora and fauna. Measures must be taken to avoid damage through compaction, even when specially designed machinery is used to reduce ground pressure. Frequency - Annually Maintenance of water levels A suitable outlet control should be installed to regulate the water level of the wetland. Adjustment of water levels may be required during planting or periods of drought/flood. In the case of drought, pumping of water from the river Severn will be required. Frequency - As required. Control of weed growth Periodic flooding of the wetland may be necessary to control weed growth when the reeds and aquatic plants are initially growing to maturity. Frequency - As required. Monitor For blue algae as this is a health hazard for humans and dogs. Check inlets/outlets/sediment traps and clear any blockages. Frequency - Monthly and before/after heavy rain/flooding events. Rubbish - Check and remove any rubbish and other inorganic debris from the wetland as required in order to keep an attractive in appearance.
Pest control Plant replacement may be required if the vegetation has been devastated by pests. If the problem is noticed in time it may be possible to spray the plants. It should be noted that any use of herbicide or pesticide in or near water courses will require prior approval of the Environment Agency. Reed bed harvesting Mechanical cutting and mowing of reed beds Marginal reed beds can be cut for high quality reeds for thatching, which is an age old tradition which has helped maintain extensive areas of wetlands. A number of birds such as bittern and reed warbler, and a wide range of invertebrates, are associated with cut reed beds. The Alney Island wetlands are small scale and are mix reed and sedge dominated habitats. Cutting or mowing has become a widely practiced conservation management technique to maintain marginal reed beds allowing more flexibility, and scope to adapt the method of mowing or
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15
16
17
18
Wetland Habitat SD
CP
7.00 SD CS
CS
SD
Reed Beds
11.00 HG GC
CP
Marginal /Emergents
CS
SD
HH
CP
CP
SD
CS 7.00
CP BB
HH
CS
SD
7.00
7.00
RS
BW
RS
LG
AA
Aquatics
GC
ED ED
GG
GG
AA
CP
PP BR
CS
50,000
SD
PP
BB
BR
BK ED
ED
FF
CP
SD 10.00
FF
LG
HG
BK 67,257
9.00
Open Water
GC
9.00
GC
BK
BW ED BW
9.00
11.00
Wet Woodland and Carr Mix
BK
BK
BR
10.00
11.00
12.00
Dry Woodland
ED
11.00
ED ED
11.50
BW
17,257
13.00 12.00
GC
ED
BW HG
BK
12.50
10.50 BK Angle -39.25 from North
14,584
10.00 9.50
GC PP
DD
HG DD
CC
HG EE
13.00
13.00
LG
Rain Gardens
GC 11.00
PP 11.00
BW
th 12.50 bh 11.00
12.50
CC
LG
th 12.50 bh 11.00
Pollarded Willows/willow spilling (throughout the landform)
Bio-filtration Swales
BK
11.00 CP
ED
12.00 LG EE
11.00
GC
11.00
11.50
11.00
Extensive Living Roof
ED 10.50 10.00 9.50
1.
Bioretention tree pits
Ground Floor
1:200
19