Rural Design Guidelines

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   Westmeath Rural Design Guidelines • Green Design - Sustainable Building for Ireland. Mc Nicholl, Lewis (Eds) Energy Research Group UCD, European Commission Directorate General XVII for Energy, The Office of Public Works, RIAI, 1996 • Source Book 2000 Ireland's Social, Environmental and Holistic Directory A Guide for Green, Ethical and Healthy Living, Woods & Philip (Eds) 1999 • Construct Ireland Newsletters Vol 2, Issues 2 and 6 • The Climatic Dwelling, O’Cofaigh, Olley, Lewis. Energy Research Group UCD, 1996 Acknowledgements We acknowledge the invaluable assistance of Sustainable Energy Ireland’s Renewable Energy Information Office which provides expert independent information and advice on the development of all renewable energy technologies. Particular thanks goes to Mr Xavier Dubuisson. For further information contact: Sustainable Energy Ireland Renewable Enegry Information Office Shinagh House Bandon Co. Cork t + 353 23 42193 f + 353 23 29154 e [email protected] w www.sei.ie/reio.htm 67

2. Page 72(read from a scan)

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   Westmeath Rural Design Guidelines 4 Site Assessment for On-Site Domestic Waste Water Treatment Key Documents 1 DoELG /EPA Manual/GSI 2001 Groundwater Protection Responses For On-Site Wastewater Treatment Systems For Single Houses. A joint publication by the Department of the Environment and Local Government, Environmental Protection Agency and Geological Survey of Ireland 2 EPA, 2000. Treatment Systems For Single Houses. Wastewater Treatment Manual, Environmental Protection Agency Purpose To determine whether an on-site system can be developed, and if so, the type of system/s that are appropriate and the optimum final disposal route of the treated water. Site assessment should be carried out by a qualified professional, and must be systematic and rigorous. It consists of: Desk Study • Collect relevant map information, know up-to-date regulations and consult the framework for the protection of groundwater by GSI, DEHLG and EPA • Establish whether there are surface water features, such as rivers, canals or streams, wells, springs, lakes in the vicinity. These will indicate a high water table, which will require vigilance to ensure there will be no danger of pollution from wastewater treatment. Check contours. Does the land steeply slope to a water-course? • Check whether the site is in or adjacent to a Natural Heritage Area, Special Area of Conservation etc. or an archaeological site. If so, contact the Planning Authority and DEHLG prior to performing trial holes assessments or percolation test On-Site Evaluation • Visual Assessment – Identify surface features, topography, landscape and land use, slope, vegetation (rushes, yellow flags, willows and alders indicate poor percolation characteristics, while grasses, trees and ferns may indicate suitable percolation characteristics), ditches, surface water and water courses, ponded water, wetlands, and drainage conditions, constructed site features such as adjacent roads, neighbouring dwellings, position of wells and existing septic tanks and percolation areas and their local density, geological features such as rock outcrops and exposures of subsoil, and conceptualise the underground water regime, springs, karst features – (indicates high permeability zone), flows and their direction. Identify weather conditions at time of inspection • Measured evaluation – check that there is a sufficient area for the on-site system by taking account of the separation distances in the EPA Manual, Groundwater Protection Responses for On-Site systems • Trial Hole – Evaluates the subsoil texture, depth to bedrock and water table. The hole should be as small as is practicable • Percolation Tests – Establish percolation capacity of the subsoil to avoid ponding or over-rapid movement of wastewater to the water table, and calculate piping length Decision-making Evaluate the site's health and environmental sensitivity, and determine whether: • Site is unsuitable • Site may prove suitable following site improvement works or by use of an alternative filter system or a mechanical aeration system • The site is unsuitable for a conventional septic tank with percolation because of : o High water level in subsoil o Shallow depth to hard rock o Poor percolation o Percolation rate too fast • More information is required before a decision is possible. 68

3. Page 73(read from a scan)

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   Westmeath Rural Design Guidelines Site Size Appropriate site size can depend on: A Whether wells are used on-site or within 60.0m B Existing NO3 levels in area (ie the number of other septic tanks close by) C Conclusion drawn on specific site conditions and the resulting required minimum distance between well and on-site wastewater system General Conclusion • Areas with deep, free-draining, permeable sub-soils are most desirable for on-site systems, with the exception of low-lying areas where the water table may be too close to the surface • Areas with poor percolation characteristics, (particularly in depressions or at the bottom of slopes), and shallow bedrock may be unsuitable or suitable only if an advanced wastewater system is used • Where steep slopes are present, (greater than 1:5), installation of the percolation area may not be feasible • Percolation systems should always be set back recommended minimum distance from shoulder of head slopes • Long and steep slopes will generally receive more run-off water • Percolation areas not allowed in proximity to karst features (high permeability limestone) • Minimum separation distances for recognised site conditions must be adhered to • Septic tank or percolation area cannot be situated in proximity to surface water features. Recognise minimum regulatory distances • A high density of local development that impinges on ground water quality (eg septic tanks or farmyards), may restrict development or require a more sophisticated method of effluent treatment] • Septic tank and/or wastewater systems should be desludged annually Acknowledgements We acknowledge the invaluable assistance of Mr Donal Daly of the Geological Survey of Ireland. 69

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   Westmeath Rural Design Guidelines 5 Main Types of Domestic Wastewater Treatment The objective of all waste water systems is to provide safe, effective treatment that is non-polluting for the immediate site, for neighbours and for the natural, wider environment. When systems fail, it is normally due to poor design, siting, installation and maintenance. Many of Ireland's septic tanks are defective. Failure of a system can be identified by the following: Signs of Fallure: • Surface ponding • Surface water pollution • Groundwater contamination • Odour nuisance • Insects, rodents at large At Risk: • Wells and ponding of effluent • Groundwater/aquifers • Wetlands, lakes and shell fish areas • Streams and beaches • Human health due to exposure to pathogens Types of Systems The type of system appropriate to the site and sub-soil type should be made by a qualified professional. Some sites may be unsuitable for any on-site wastewater system. 1 Traditional: Septic Tank with Percolation Area The traditional septic tank relies on anaerobic digestion to break down solids and a percolation area to ensure safe disposal of the effluent. Septic tank systems are suitable and effective in areas of deep, (ie greater than 3.0m), free-draining subsoil. • Septic Tank It comprises a properly sized, watertight, twin-chambered underground tank. Incoming effluent arrives in a 100mm diameter pipe from the dwelling is slowed so that solids settle and lighter materials float to the top, thereby reducing clogging in the percolation area. Anaerobic digestion in the tank removes up to 50% of solids but does not significantly remove bacteria and organisms. The remaining sludge will require regular removal by recognised contractor, so vehicular access is crucial. (Tank should be minimum regulatory distance from the dwelling and from neighbouring dwellings, from wells/streams, springs, watercourses or public roads, and from any site boundary.) • Percolation Area This is the underground distribution system fed by the septic tank, where absorption and purification through aerobic treatment of effluent occurs in the soil. It must be installed strictly in accordance with regulations. The subsoil must be carefully assessed to ensure that percolation of the effluent is effective and the system must be capable of long-term use. The percolation area is generally located downstream of the septic tank and comprises long, level, narrow trenches which distribute the effluent evenly. On sloped sites, a system known as serial distribution can be used, whereby longer trenches are installed along the site contours and effluent flows from the highest trench to the next lower trench and so on. 2 Advanced Systems – with Irish Agreement Board Certificate – Advanced systems are complete on-site package wastewater treatment and disposal systems, which may be appropriate in areas not suited to the traditional septic tank system, eg. where the water table or bedrock is shallow or sub-soils have poor drainage. They provide a higher level of sewage treatment, thereby reducing the concentrations of contaminants and reducing potential hazard. They also require a percolation area for ultimate treatment and disposal of the effluent. Choice of system should be made by a qualified consultant and must respond to sub-soil type and consider capital and running costs, and 70

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   Westmeath Rural Design Guidelines experience of the system (ie durability, ease of operation and frequency required for maintenance). Types of Systems: • Intermittent soil or sand filters • Peat Filters • Other Filters (plastic foam and geosynthetic) • Mechanical Aeration - Mechanical Aeration systems include: BAF systems (Biofilm aerated systems) RBC systems (Rotating biological contactors) SBR systems (Sequencing batch reactors) • Constructed Wetlands - Wastewater from the septic tank is purified by micro-organisms attaching to the reeds and support media. The wetlands should be securely fenced and regularly, (ie weekly,) monitored. A polishing filter is required as tertiary treatment 3 Combined Systems Capable of serving more than one house. (Refer to BS 6297:1983 "British Standard Code of Practice for Design and Installation of Small Sewage Treatment Works and Cesspools", EPA "Wastewater Treatment Manual: Treatment Systems for Small Communities, Business Leisure Centres and Hotels," (for pop. 10 – 500). Note that septic tank and wastewater treatment systems should be desludged annually References • Septic Tank Maintenance by Ciaran Gillen (Biofuture) - Construct Ireland Issue 6 Vol. 2 • Ireland’s Domestic Waste Water Problem by Pat Kennedy - Construct Ireland Issue 2 Vol 2 • DoELG/EPA Manual/GSI 2001 Groundwater Protection Responses for On-site Wastewater Treatment Systems for Single Houses. A joint publication by the Department of the Environment and Local Government, Environmental Protection Agency and Geological Survey of Ireland • EPA, 2000. Treatment Systems for Single Houses. Wastewater Treatment Manual, Environmental Protection Agency Acknowledgements We acknowledge the invaluable assistance of Mr Donal Daly of the Geological Survey of Ireland. Proprietary system wastewater treatment plant: ‘Enviropak’ system, showing above ground visibility of the underground tank 71

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   Westmeath Rural Design Guidelines 6 On-Site Wells for Domestic Drinking Water Ireland’s groundwater provides about 25% of drinking water. Its protection from contamination is crucial to health and the environment. In rural areas, there are many thousands of private and group wells and springs in use, and several thousand more are drilled annually. Groundwater is usually presumed to be pure and safe to drink due to its filtering and cleansing process through subsoil cover and rock medium. However problems can occur due to natural ground conditions and human activities. The main sources of pollution are farmyard wastes and septic tank effluent. Other sources include land spreading of pesticides and fertilizers, polluted surface water, urban areas, landfills, spillages and leakages. "...in many areas, at least 30% of the domestic and farm wells are contaminated, usually by faecal bacteria. In some vulnerable areas, more than 50% are contaminated at some time during their use." (1) Main Reasons for Contamination of Wells • Proximity to or down-slope of polluting elements such as silage pits, septic tanks, percolation areas • Polluting elements, such as percolation areas, located in zone of contribution, (ZOC), ie the ground area contributing water to the well • Percolation zone of waste water treatment located in vulnerable area where contaminants are not sufficiently purified before reaching the water table • Poor sanitary protection around the well itself, ie poor construction • Concentration of septic tanks and well-water supplies in the area Locating the Well On-site location of a well for domestic water consumption must be considered in tandem with the design for wastewater treatment. Location must take into account safe distance between effluent treatment systems that are proposed on site, and those existing on neighbouring sites. Location is also affected by distance to boundary, and land use. The following should be considered: • The well should be convenient to the house and to a power supply • It should preferably not be located down-slope from polluting sources such as silage pits, septic tanks, percolation areas, farm waste heaps, diesel tanks. Regulatory distances must be observed • Whether the site is in or adjacent to a Natural Heritage Area, Special Area of Conservation etc. or an archaeological site. If so, contact the Planning Authority and DEHLG prior to any works Locating the Pump House Consider the following: • Preferable location is adjacent to, but not over, the borehole • Design in keeping with main residence, using same materials if possible • Consider individual and future requirements at time of installation • Do not store potentially polluting liquids in the pump house If the pump house must be over the borehole then ensure: • Ready access for maintenance • Access for lifting gear, through roof or by overhead girder • Locate the door directly opposite the borehole The Pump Choice should be by specialist contractor and should be based on assessment of 5 issues: 1 Max pumping rate required, in litres/hr 2 The Suction Head – ie the vertical distance from ground level to pumped water level when pumping 3 The Delivery Head – ie. Vertical distance from the well-head (ground level), to the highest point in supply system, eg attic storage tank 4 Type of power supply, usually electricity, voltage, frequency and number of phases 72

7. Page 77(read from a scan)

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   Westmeath Rural Design Guidelines 5 Quality of water – eg corrosive water will require special precautions 6 In addition to nitrate levels in drinking water as a deciding factor in the siting of a well, manganese and iron levels should also be taken into consideration Water Protection Measures • Wellheads should be constructed so as to ensure that surface water and shallow groundwater, which are likely to be polluted, cannot enter the well • A sample of water should be analysed by a reputable laboratory after the well has been installed, disinfected and pumped for a while, and preferably after heavy rainfall • Ultraviolet systems can be installed to treat water in vulnerable areas, and reduce the likelihood of bacterial or viral contamination • In relation to surface water features, EPA 2000 gives minimum separation distances for siting of waste water systems • Wells should be disinfected in late Autumn and at least annually. (Details can be obtained from the Geological Survey of Ireland) Summary • Work out how much water you need – then allow a little extra to allow for future increases in your needs • Seek information from your neighbours, and from anyone whose experience may be useful, about underground water in your area • Choose a convenient, clean site for your well • Hire a well driller with insurance and a good reputation – not necessarily the cheapest • Have a short, simple written contract drawn up for the work of sinking the well • Make sure the well is protected from pollution • Pump choice should be made by an expert. Include a maintenance contract • Have a proper pump test, (4-hour) carried out to determine the yield of the well • Group schemes should be encouraged in rural areas, because the drinking water supply receives a certain level of treatment and is monitored regularly by the Local Authority and the Health Board • Finally, send the Geological Survey of Ireland a card giving details of the well – even if it was a failure! Well grant record sheet available from the County Council Sources 1 Water Wells A Guide to the Development of Groundwater for Small Residential and Farm Supplies by GSI 1979 (Information Circular 79/1) References • Septic Tank Maintenance by Ciaran Gillen (Biofuture) Construct Ireland Issue 6 Vol. 2 • Ireland’s Domestic Waste Water Problem by Pat Kennedy Construct Ireland Issue 2 Vol 2 • Water Wells A Guide to the Development of Groundwater for Small Residential and Farm Supplies by GSI 1979 Acknowledgements We acknowledge the invaluable assistance of Mr Donal Daly of the Geological Survey of Ireland. Drilling for water 73

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   Westmeath Rural Design Guidelines Appendix 7 Native hedgerow species and trees suitable for planting in Co. Westmeath The following native hedgerow species are recommended for planting in Co. Westmeath. Plants of local provenance are always preferable and do not interfere with the genetics of other wild populations. Hawthorn - Crataegus monogyna Blackthorn - Prunus spinosa Hazel - Coryllus avellana Elder - Sambucus nigra Holly - Ilex aquifolium Spindle - Euonymus europaeus Guelder Rose - Viburnum opulus Crab Apple - Malus sylvestris Damson - Prunus domestica Willow - Salix species Gorse - Ulex europaeus Elm - Ulmus glabra Yew - Taxus baccata Trees Trees provide an attractive element to any garden or home and help to blend new housing into the countryside. While over 500 species of trees are found growing in Ireland only about 25 are native. As with hedgerows native trees are more ecologically valuable supporting more birds and insects. The following trees are most suitable for planting in Co. Westmeath. Native tree species suitable for planting in Co. Westmeath Ash - Fraxinus excelsior Oak - Quercus sp. Willow - Salix sp. Birch - Betula sp. Holly - Ilex aquifolium Damson - Prunus domestica Wild Cherry - Prunus avium Hazel - Coryllus avellana Crab Apple - Malus sylvestris Rowan - Sorbus Aucuparia Scots Pine - Pinus sylvestris Other trees such as Horse Chestnut, Field Maple, Beech, Hornbeam, Larch, Lime, Sycamore and Poplar are non native, but can provide attractive landscape elements and have some biodiversity value although less than native species. Planting clumps of trees is preferable to single trees, and biodiversity value can be further enhanced, by connecting new planting with hedgerows, woodland edges and rivers and ponds. It is important to take into account the space requirements for growing trees and also the type of scheme and scale of planting. The distance between a tree and the nearest building should not be less than the expected maximum height of the tree at full growth. Any plans for building extensions should also take this into consideration. Choosing appropriate planting for your scheme demands consideration of exposure, degree of maintenance and availability of trees. The more exposed the site the smaller the trees that should be planted. Generally the smaller the tree the faster it will become established after planting. Nursery stock is available in whips and transplants, medium-sized trees, large trees and semi-mature trees. Larger trees while satisfying a demand for quick landscape effects are more expensive, require good aftercare and maintenance and may experience die-back. Avoid buying trees and shrubs that have almost reached their full size as they are less likely to thrive 74

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   Westmeath Rural Design Guidelines than those available at around a third or a half their maximum size. The best time to plant trees is between November and March when the tree is dormant. Existing trees should be protected during the course of any site construction by establishment of a 1m high fence around the tree and 3m from the trunk of the tree. For further information consult the following publications or contact the offices of Westmeath Co. Council. References Conserving Hedgerows - The Heritage Council, 2001. Available from Planning Department, Westmeath Co. Council. The ABC of planting trees, Crann 2004. Co. Westmeath Hedgerow Survey Report, Westmeath Co. Council 2005 Biodiversity and Development in Co. Westmeath. Good practice guidelines for householders, developers and the local authority. Series of leaflets available from Westmeath Co. Council. 75

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    Westmeath Rural Design Guidelines Appendix 8 Acknowledgements The images in these Guidelines and the Appendix were taken for the most part by the authors, and mainly in County Westmeath, although some are from other counties where the emphasis was felt to have been better illustrated by using them. Additionally, the authors made a request through the RIAI Bulletin for further images, which would show modern examples of successful design in the countryside. We would like to thank those architects who were kind enough to take the trouble to contact us. We were able to use a small number only given the specific focus of the material. We would like to thank those whose work we have illustrated. These illustrations have been an indispensable element of the guidelines; credits for those images and the page numbers is as follows: Robinson Patterson Partnership Ltd, Belfast, (project architect Neil Darby) RIAI Award 2005. Pp - Cover, 23R, 40, 49, 50 and this page Henchion and Reuter, Architects, Dublin, (project architect Martin Henchion) RIAI Award 2005, pp - Cover, 23L, 27, 44, 45 Alan Mee, Architects, Dublin (project architect Alan Mee), pp 24L top, 45, 52 bottom L Evelyn Duff, Architect, Portlaoise, (project architect Evelyn Duff), p48 Meehan, McLean Architects Ltd Arklow, (project architect Ken Meehan) pp41, 48 ICON Architecture and Urban Design. The authors illustrated some of their own projects on pp 42R, 43, 51 Illustrations of other new buildings were photographed from the roadside and their architects or designers are unknown. The drawings and explanatory sketches are by Delphine Geoghegan. 76

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