I am deputy chief executive and director of services at Leitrim County Council with responsibility for economic development, planning and infrastructural services with the council.
The Water Services Act 2007 places a duty of care on homeowners to ensure that all wastewater treatment systems are kept so as not to cause a risk to human health or the environment or create a nuisance through odours. For new builds, site characterisation must be carried out in accordance with the EPA code of practice for wastewater treatment and disposal systems serving single houses 2009. In regard to this code of practice particular attention is drawn to the provision that where the T-test is in excess of 90 then the site is unsuitable for discharge of treated effluent to the ground.
In County Leitrim, the landscape is characterised by drumlins which contain high clay content. Unfortunately, due to the underlying nature of the sub-soils which are present across the majority of our county, estimated at 87% of our soils, the soil percolation tests fail to meet the acceptable percolation rates required to comply with the EPA code of practice and the sites are deemed unsuitable for discharge of treated wastewater or effluent to the ground.
This is proving to be a significant impediment to the granting of planning permission for individual dwellings in the countryside by Leitrim County Council's planning authority and indeed is preventing many prospective applicants making applications in the first instance as agents are aware that the subject sites will be deemed unsuitable once the soil percolation tests are undertaken. This situation is not unique to County Leitrim but no county is affected to the same extent as County Leitrim.
The number of planning permissions granted for individual houses reliant on individual wastewater treatment systems is set out in a table which I have supplied to the committee with a copy of this statement. It ranges from four in 2017 to 13 in 2018. The figures in preceding years from 2012 are similar.
Leitrim is a sparsely populated county with the 2016 census showing a population of 32,044. The county is highly rural in nature with the vast majority of the population living in a non-urban environment. This profile of the county represents the history and culture of Leitrim with a high proportion of small family farms. In the context of this fabric the imposition of the percolation standards through the 2009 code of practice has had what the council believes to be unintended consequences. These consequences are most acutely felt in the small farm holding scenario where, despite many acres of land being available, the farmer's offspring, son or daughter, who may wish to establish their home on the family farm to continue to farm the land and be of support to their aging parents, will fail to secure planning permission. The compounding effect of these restrictions for almost ten years is a contributing factor to the continued depopulation of areas of rural County Leitrim which will have a corresponding effect on the sustainability of the surrounding community and its facilities and services such as primary schools etc.
In this regard Leitrim County Council, while maintaining a responsible attitude to the protection of the environment, as is required by law, set about identifying options that could be explored to provide a wastewater treatment system solution that would be suitable, acceptable and affordable. In addition, the council has at all times maintained a responsible attitude through its county development plan to rural planning with a variety of policies that ensure the appropriate establishment of one-off rural housing in Leitrim and would not see the restrictions of the code of practice as necessary or relevant from a rural planning control tool perspective.
The existing EPA code of practice is under review with a new document expected to be published in the next couple of months. It is anticipated that the review of the code of practice may widen slightly the acceptable parameters of percolation rates which will result in a limited number of marginal sites in County Leitrim now becoming acceptable for discharge of treated effluent to ground but, as only marginal in nature, it is felt that the Council must continue to pursue these alternative solutions.
Leitrim County Council has been pursuing innovative solutions to facilitate the design of a wastewater treatment and disposal facility that would be suitable in the poor draining soils. Through this process the council identified a treatment solution that has the potential to have a zero discharge or near-zero discharge of effluent and, if successful, would allow sites with poor percolation characteristics to treat the discharge of wastewater in a manner which was not prejudicial to public health or the protection of the environment. The nature of the wastewater treatment system is a willow-based system constructed within a sealed soil basin. The council has engaged with Dr. Laurence Gill, a professor in environmental engineering in the school of engineering, Trinity College Dublin as academic support to the process. Dr. Gill has extensive experience in assessing the operation of individual wastewater treatment systems and was co-author of the EPA publication that Deputy Kenny mentioned earlier.
The willow evapo-transpiration system consists of a sealed basin that has been refilled with the original soil excavated on site in order to install an impermeable liner and distribution pipe network, which has then been planted with willow cuttings. The system receives wastewater effluent fed to the base of the basin and treated and removed via evapo-transpiration, primarily during the growing season when the willow trees have high water demand but it also occurs on a limited basis all year round. Results from 12 trial systems to date have shown that the system provides excellent pollutant attenuation greatly reducing organic, nutrient and indicator bacteria. Through the most recent design concepts the level of rainfall entering the system will be significantly reduced if not eliminated thus ensuring minimal if any overflow from the system and if such were to happen tests available already show the characteristics of such escaped liquid to be similar to ground run-off.
Currently the water pollution legislation provides for discharges to ground and surface waters. In regard to domestic waste water treatment systems there is an exemption for discharge to ground where the quantity to be discharged is less than 5 m3 per day. However, a discharge to surface waters can only occur under licence from the local authority. As a consequence a detailed application process is required in order to comply with the legislative requirements. The application process is lengthy and requires significant data collection on the identified receiving waters such as all year round flows and assimilation capacity along with a rigorous monitoring regime thereafter in regard to items such as ongoing sampling analysis, inspection chambers, record keeping and licence renewal processes. This system of licensing discharges is more designed to deal with matters such as industrial by-products rather than domestic waste water treatment systems.
A pilot scheme is currently proposed in Leitrim to further test the willow system for zero discharge, that there is no discharge or escape of effluent from the willow plantation basin at any time based on a more refined design taking learning from the trials to date. However, on other trials to date in Ireland the objective of zero discharge from the system has not been fully realised. In addition to that detailed earlier in regard to attenuation what is also known is that the willow system does deliver a significantly reduced level of effluent discharge, with discharge only in winter months.
Taking into account the research already available what is now required is a means to dispose of the limited, if any, resulting discharge proven to be primarily arising from rainfall. The option for this discharge is to proceed to surface discharge only, given that the ground conditions on the subject site prevents discharge to ground. Given the proven reduced scale of effluent, its proven standard and the fact that the discharge arises during the wetter times of the year, there is a case for the development, in the context of output from these systems, for a less rigorous regulatory regime that is both appropriate and proportionate and which would therefore move away from the rigours of the current authorisation process for discharge to surface waters.
This reformed regulatory process can be limited to provide only for installations meeting certain design standards based on the experience of the willow systems to date, for example. The data available also provides the basis for both design guidelines for the system and design parameters for this discharge, particularly in regard to volumes, effluent standard, and so on.
Through the work carried out nationally to date, along with the work of Leitrim County Council, there is now an immediate opportunity to address the unintended consequences of the provisions of the code of practice of 2009 in regard to sites of low permeability. This opportunity relates to the use of the domestic wastewater evapotranspiration treatment system, coupled with the requested regulatory reform under the Local Government (Water Pollution) Act 1977. This would provide a clear option for the provision of a new rural dwelling where the housing need to be accommodated in rural Leitrim is of an absolute requirement, which in turn could be of general application in areas of the country with similar soil conditions. The pilot scheme in Leitrim will continue to pursue the objective of zero discharge, which would be the ultimate preferred outcome.