2. Discharges to waters

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2 There are 8 discharge points from the agglomeration. The primary discharge (SW001 Note 1 ) occurs into the Folly Stream, which discharges into Lough Leane (1km downstream of the WWTP outfall). There are 7 storm water overflows, which either discharge to Lough Leane directly, or via the River Flesk, the Folly stream, or other small streams. There are no secondary discharges from the agglomeration. The town has a partially combined sewer system which has significant capacity deficits in some areas leading to problems with storm water overflows. The majority of the wastewater arising in the agglomeration is commercial in origin (59%), with the remainder originating from domestic and trade effluent sources (29% and 12% of total respectively). Landfill leachate is not accepted at the WWTP, and there are no industrial sources of effluent in the agglomeration. Leachate from a transfer station is accepted at a rate of 0.006% of the total influent volume to the plant. Sludge is accepted from WWTPs in some smaller agglomerations. The WWTP process at Killarney is based on activated sludge with nutrient removal. The treatment consists of screening and grit removal, phosphorus removal by ferric dosing, oxidation, by both mechanical and diffused aeration, (which incorporates a denitrification process) and settlement. Sludge is treated onsite by autothermal thermophilic aerobic digestion. 2. Discharges to waters Treated effluent is discharged through SW001 into the Folly Stream at a normal rate of approximately 10,436m 3 /day, and a dry weather flow of 6,500 m 3 /d. The plant is designed to attain the Urban Wastewater Treatment Regulations standards of 25:125:35 (BOD:COD:SS), total phosphorus of 2mg/l and total nitrogen of 15mg/l. Due to the nutrient sensitive nature of Lough Leane, the Department of the Environment, Community, and Local Government (DoECLG) required, as part of the planning approval for the most recent upgrade of the plant, that total phosphorus in the final effluent should not exceed 1mg/l, and the plant currently achieves this. Monitoring data for SW001 was submitted to the Agency as part of the application process. This data has been generated as a consequence of the monitoring regimes imposed by the Urban Waste Water Treatment (UWWT) Regulations, 2001 (S.I. No. 254 of 2001) as amended. Based on the data submitted as part of the application, the Killarney agglomeration can be regarded as compliant with the requirements of these Regulations. The monitoring undertaken did not indicate that elevated levels of any dangerous substances, as defined in the Dangerous Substances Directive (2006/11/EC), were being discharged. There are 7 Storm Water Overflows in the agglomeration, SW002 to SW008 Note 1. SW002 and SW003 are overflows from storm water holding tanks at the WWTP, which each have a capacity of 2,477m 3. Three submersible pumps fill the storm tanks and each is capable of pumping 1,050 m 3 /hr. On overflow, these discharge to the Folly Stream. The remaining SWOs arise from the collection network. SW006 and SW008 discharge to the River Flesk, which drains to Lough Leane, and the remainder discharge to Lough Leane (either directly or via small streams). Four of the SWOs are associated with pumping stations (SW004, SW005, SW006 and SW007), each of which are fitted with a duty and standby pump. Note 1: The discharge point reference numbers SW001 to SW008 in the Recommended Licence correspond with discharge point reference numbers SW1 to SW8 in the licence application and its associated drawings. 2

3 The EPA s publication Focus on Urban Waste Water Discharges in Ireland (EPA, 2012) states that there is a high probability that the Killarney agglomeration is the principle cause of pollution in the River Flesk (which receives two storm water overflows). In addition, it is noted that the Appropriate Assessment submitted with the application identifies concerns about large quantities of untreated sewage which are overflowed to the storm water holding tanks in wet weather, giving rise, in turn, to excessive flows in the Folly Stream. It is unknown whether all the storm water overflows in the agglomeration comply with the requirements of the Department of the Environment, Community, and Local Government (DoECLG) document Procedures and Criteria for Storm Water Overflows (DoEHLG, 1995). Therefore, Condition 4.13 of the Recommended Licence (RL) requires an assessment of the storm water overflows compared to DoECLG standards and the identification of remedial measures. The programme of improvements required by Condition 5 must also include an assessment of SWOs and the improvements identified shall be implemented by the 31 st December 2020 (Schedule C.3 Improvement Programme for Storm Water Overflows). The application states that infiltration of groundwater is occurring in the wastewater collection system. This issue will be addressed under Condition 5 of the RL, where the licensee is required to assess the integrity of the waste water works having regard to groundwater infiltration and to develop a programme of infrastructural improvements accordingly. 3. Receiving waters and impact The Folly Stream receives the primary discharge. This small stream flows into the north east shore of Lough Leane at Ross Bay, approximately 1km downstream of the primary discharge. Lough Leane is drained by the River Laune to the north west of the Lough. The Folly stream and the River Laune are part of the Laune, Tributary of Laune Waterbody. Lough Leane is a water body in its own right. As the Folly Stream drains to Lough Leane, the following table summarises the main considerations in relation to the Folly Stream and Lough Leane. Table 1.0 Receiving waters Characteristic Classification Comment Receiving water Folly Stream Freshwater stream, name and type Segment code: SW_ 22_2629. Lough Leane Freshwater lake which forms the Lough Leane Waterbody, WFD Code SW_22_185. Resource use None No drinking water abstractions in Lough Leane Amenity value Applicable Regulations General, tourist area Surface Water Regulations Note 1 Folly Stream: Non-Compliant Lough Leane: Compliant 3

4 UWWT Regulations Note 2 Lough Leane: Nutrient Sensitive EPA monitoring stations Biological quality rating (Q value) WFD status Several WFD monitoring stations in Lough Leane. None in Folly Stream. None Folly Stream: Not assigned Lough Leane: Good Based on 2011 data & EPA Water Quality Report WFD Objective Folly Stream: Not assigned WFD areas protected Lough Leane: Restore by 2021 As per Laune Water Management Unit Action Plan (South Western River Basin District River Basin Management Plan 2010) Killarney National Park SPA (Site Code ), Note 1: Note 2: Killarney National Park, Macgillycuddy s Reeks and Caragh River Catchment SAC (Site code ) European Communities Environmental Objectives (Surface Water) Regulations 2009, S.I. No. 272 of Urban Waste Water Treatment Regulations, 2001, S.I. No. 254 of 2001, as amended. Folly Stream The Folly Stream is located approximately 1km south west of Killarney town centre. The primary discharge and two of the SWOs are the only point sources of discharge to the stream. The ambient monitoring data (once-off monitoring) provided in the application indicates that the good status surface water standards for ammonia and BOD are exceeded in the Folly Stream upstream and downstream of the primary discharge point and the good status standard for orthophosphate is exceeded downstream of the discharge. Ross Bay Ross Bay is a shallow inlet of Lough Leane with depths of between 1 and 3 metres. The Bay comprises 3% of the overall lake area and receives the flow from the Folly Stream. The entire Lough Leane Waterbody (which includes the Ross Bay area) has already achieved Good Status. However, the monitoring data for the Ross Bay area alone 4

5 shows this area of the lake to be of Moderate status for chlorophyll and total phosphorus. The EPA s Office of Environmental Assessment (OEA) has confirmed that the monitoring points in Ross Bay are not assessed for WFD purposes and therefore do not impact on the overall Good status of the Lough Leane Waterbody. These monitoring points will be used instead to facilitate an investigative monitoring programme on this area of the lake. In addition, OEA have confirmed that Ross Bay is not considered a separate water body, and therefore does not in itself need to attain Good Status for WFD purposes. The monitoring data for Ross Bay demonstrates that nutrient levels reduce with distance from the mouth of the Folly Stream. This may suggest that the Killarney WWTP is the main source of nutrients to the Ross Bay area. Lough Leane Lough Leane is the largest of the Killarney lakes and has a surface area of 1978ha. The mean depth of the Lake is 13m and it has a maximum depth of 60m. The Lough Leane catchment contains numerous rivers, streams and lakes, and drains an area of 560km 2. The River Laune flows from Lough Leane to reach the sea just north-west of Killorglin after a distance of approximately 22km. The River Laune is a very good Spring Salmon fishing river, but is not designated a Salmonid water. Lough Leane is designated a sensitive area in the UWWT Regulations. Nutrient levels in the Lough have improved significantly in the last 10 years. The Lough Leane Catchment Monitoring and Management System (LLCMMS) is a major catchment based initiative developed over 4 years ( ) aimed at arresting the eutrophication process in the Lough. It identified significant inputs of phosphorus to the Lough from agriculture (primary source), urban agglomeration and industry, septic tanks and forestry, in addition to natural background loading. The report identified that improvements made to the Killarney WWTP facilities have helped improve the quality of water in the Lough, particularly in the Ross Bay area. The Lough Leane Waterbody has an overall status of Good according to the EPA s Water Quality Report The monitoring data collated by OEA in 2011 confirms that this is still the case. As the status of the Lough prior to 2007 was Moderate, the Laune Water Management Unit Action Plan (WMUAP) gave an extended objective date of 2021 to the Lough, mainly due to the gley soils and karst geology within the catchment. Killarney WWTP is identified as a point pressure in the WMUAP as it discharges to a protected area and there is insufficient assimilative capacity for BOD at the discharge point. Therefore the WMUAP identifies Killarney as an agglomeration that requires further investigation prior to capital works. Impact of discharges The assessment of the impact of the discharge on the Folly Stream considered the waste water composition and quantity, receiving water monitoring results, and assimilative capacity calculations. A dilution factor of 1.7 is available on the basis of normal discharge volume and 95%ile flow in the River. Table 2 below presents the results of assimilative capacity calculations for the primary discharge, with reference to relevant water quality standards. Background concentration values shown in the table are taken from monitoring conducted for the application. However because the background levels for ammonia and BOD exceed the Surface Water Regulations Good Status standards in the Folly Stream, it is the Notional Clean River Values in the table, and not the measured 5

6 background concentrations which have been used to calculate the predicted downstream concentrations as shown in the table. This is because the purpose of the table is to show the impact of the discharge with respect to water quality standards, and the sources which give rise to the background concentrations are outside the control of the licence. Table 2.0 Assimilative Capacity Parameter Background Concentration (mg/l) Notional Clean River Values Note 1 Proposed ELVs for discharge from SW- 1 (mg/l) Contribution from primary discharge (mg/l) Predicted downstream concentration (mg/l) Relevant standard (mg/l) BOD Note <2.6 Note 2 BOD Note <2.6 Note 2 PO 4 -P Note <0.075 N PO 4 -P Note <0.075 N Note <0.140 N Total Ammonia ote 2 - N Total Note <0.140 N Ammonia ote 2 - N Note 1: Notional clean river values for AC based on 1/5th of the mean High Status standard in the European Communities Environmental Objectives (Surface Waters) Regulations 2009 Note 2: European Communities Environmental Objectives (Surface Waters) Regulations 2009, 95%ile standards Note 3: ELV required to ensure good status standards are not breached. Note 4: ELV that can be achieved by the WWTP now. ote 2 ote 2 The assimilative capacity calculations above highlight that with only 1.7 dilutions, the Folly Stream cannot accommodate the current discharge from Killarney WWTP, even though the WWTP operates well within its design parameters and the p.e. loading to the plant is considerably below the design capacity of the plant. To ensure good status standards in the Folly Stream are met, stringent ELV s are required, particularly for orthophosphate and ammonia. The plant will need to be significantly upgraded to meet these ELV s. A WFD objective has not been assigned to the Folly Stream, however as Lough Leane has been given an extended objective date of 2021, this date is assumed to be relevant to the Folly Stream also. Schedule A: Discharges of the RL requires the licensee to meet the more stringent ELV s of 4mg/l BOD, 0.1 mg/l orthophosphate and 0.1mg/l total ammonia from the 1 st January Alternatively, the applicant has the option to relocate the primary discharge point by the 31 st December Condition 5.2(d) provides for the applicant to submit a proposal for the relocation of the outfall where necessary. It should be noted that the relocation of the outfall will require a review of the licence to determine the impacts of the new discharge point. In addition, if the relocation is carried out, Condition 4.18 of the RL requires the primary discharge to the Folly Stream to cease by 1 st January

7 In the interim, ELVs have been set for BOD, COD and SS which are in line with the plants treatment capabilities and the UWWT Regulation requirements, and should ensure no further deterioration will take place within the relevant water bodies. The Folly Stream is not nutrient sensitive, and therefore the UWWT Regulation requirements regarding total nitrogen and total phosphorus do not apply in this instance. However, Lough Leane, 1km downstream of the primary discharge, is designated sensitive. Therefore, an emission limit value of 15mg/l for total nitrogen has been set to protect the nutrient sensitive water of Lough Leane. An emission limit value of 1mg/l is set for total phosphorus to reflect the requirements of a Department of Environment, Community and Local Government s letter to the applicant on the 28 th February ELVs have also been put in place for ammonia and orthophosphate which are in line with the plants current treatment capabilities. Schedule A: Discharges of the RL sets ELVs for the primary discharge. Monitoring of the discharges will take place as per Schedule B: Monitoring. 4. Ambient Monitoring Condition 4.17 requires the licensee to report annually on the chemical and ecological status of the receiving water and demonstrate the discharge s impact on the status of the receiving water to determine if it is causing or contributing to deterioration in Lough Leane. As there is a comprehensive monitoring programme already in place at Lough Leane for the purposes of the WFD and as regular monitoring is also carried out in the Ross Bay area, Condition 4.17 facilitates the licensee to avail of such monitoring in fulfilment of the requirements of Schedule B.4 Ambient Monitoring. 5. Combined Approach The Waste Water Discharge Authorisation Regulations, 2007 (S.I. No. 684 of 2007) specify that a combined approach in relation to licensing of waste water works must be taken, whereby the emission limits for the discharge are established on the basis of the stricter of either or both, the limits and controls required under the Urban Waste Water Treatment Regulations (S.I. No. 254 of 2001) as amended and the limits determined under statute or Directive for the purpose of achieving the environmental objectives established for surface waters, groundwater or protected areas for the water body into which the discharge is made. The RL as drafted gives effect to the principle of the Combined Approach as defined in S.I. No. 684 of Programme of Improvements The applicant reports that the sewage collection network within the Killarney agglomeration has significant capacity deficits in some areas and there is evidence of deficiencies in handling storm-water. A scheme to upgrade the network, with an estimated overall cost of over 10million, is proposed. This scheme was on the Water Services Investment Programme (WSIP) for but is not included in the WSIP for No works are planned for the WWTP at this stage. However, as stringent ELVs apply to the primary discharge from the 1 st January 2021, the plant will need to be upgraded to meet them. Alternatively, the applicant may choose to relocate the 7

8 primary discharge point by the 31 st December A licence review will be required to accommodate the relocation of the primary discharge point. In addition, the SWO s in the agglomeration are to be upgraded (if necessary) by the 31 st December Compliance with EU Directives In considering the application, regard was had to the requirements of Regulation 6(2) of the Waste Water (Discharge) Authorisation, Regulations, 2007 (S.I. No. 684 of 2007) notably: Drinking Water Abstraction Regulations 1989 [S.I. No. 294 of 1989] No drinking water abstractions occur downstream of the primary discharge. Urban Waste Water Treatment Regulations 2001 [S.I No. 254 of 2001], as amended The Folly Stream, which receives the primary discharge, is not designated a sensitive water under the Urban Waste Water Treatment Regulations 2001 [S.I No. 254 of 2001], as amended. However Lough Leane, 1km downstream of the primary discharge, is designated sensitive under the Regulations. The p.e. of the agglomeration is between 10,000 and 100,000. The concentration limits of Part 1 of the Second Schedule of the Regulations apply to the discharge (25mg/l BOD, 35mg/l SS, 125mg/l COD), and the plant currently complies with these requirements. The requirements of Part 2 of the Second Schedule (2mg/l TP and 15mg/l TN) do not apply as the primary discharge does not occur directly into a sensitive water. However, to protect the nearby sensitive waters of Lough Leane, a limit of 15mg/l TN and 1mg/l TP has been set for the primary discharge. The more stringent value of 1mg/l TP has been used to reflect the requirements of a Department of Environment, Community and Local Government s letter to the applicant on the 28 th February Therefore, those limits specified in the RL are determined with the aim of ensuring compliance with the Urban Waste Water Treatment Regulations 2001 [S.I No. 254 of 2001], as amended. Water Framework Directive [2000/60/EC] The RL, as drafted, transposes the requirements of the Water Framework Directive. In particular Condition 3: Discharges provides conditions regulating discharges to waters while Schedule A: Discharges specifies limit values for those substances contained within the waste water discharge. Those limits specified in the RL are determined with the aim of achieving good water quality status by 2021 in the Lough Leane Waterbody and the Laune, Tributary of Laune Waterbody. European Communities Environmental Objectives (Surface Water) Regulations 2009, S.I. No. 272 of 2009 The Folly Stream does not comply with the Good Status Limits of the Surface Water Regulations, however Lough Leane, into which the Folly Stream flows, does comply with the Good Status limits. To protect the Folly Stream, the RL requires that strict ELVs are met in the primary discharge from 1 st January 2021, or alternatively, that the primary discharge is relocated by the 31 st December In the interim, the 8

9 ELVs specified in the RL are set with the aim of not causing a breach in the standards as outlined in these Regulations in Lough Leane. Urban Waste Water Treatment Directive [91/271/EEC] The Killarney Agglomeration complies with the requirements of the Urban Waste Water Treatment Directive in terms of the level of treatment provided and the quality of the discharge. The RL, as drafted, has regard to the requirements of the Urban Waste Water Treatment Directive. Bathing Water Directive [2006/7/EC] There are no designated bathing waters located in the vicinity of the discharge. EC Freshwater Fish Directive [2006/44/EC] There are no designated salmonid waters located in the vicinity of the discharge. Shellfish Waters Directive [2006/113/EC] There are no designated shellfish waters in the vicinity of the discharge. Dangerous Substances Directive [2006/11/EC] The applicant has provided sampling results for all of the 19 dangerous substances in the primary discharge for the purposes of the licence application. The measured concentrations are not considered significant. Monitoring of receiving waters has shown compliance with the Dangerous Substances Directive. Birds Directive [79/409/EEC] & Habitats Directive [92/43/EEC] The discharges from the Killarney Agglomeration occur within the Killarney National Park, Macgillycuddy s Reeks and Caragh River Catchment SAC (site code ) and adjacent to the boundary of the Killarney National Park SPA (site code ). These sites contain at least ten habitats which are listed on Annex I of the EU Habitats Directive, and are noted for their oak woodlands, yew woodlands, blanket bog, wet heath and the wet woodland occurring on the flood plain of Lough Leane. Aquatic vegetation in the lakes of the park is diverse and includes such species as Quilwort, Water Lobelia and Shoreweed. The lowland lakes in the site, which includes Lough Leane, tend to be more species rich than the lakes at higher altitudes, with additional species such as Awlwort, Six-stemmed Waterwort and Alternate Water-milfoil. The River Flesk supports floating and submerged vegetation and rare invertebrates. The site as a whole is valuable for its rare fish species including Arctic Char, and has six bird species which are listed on Annex I of the EU Birds Directive. The Kingfisher is a species associated with the lakes and rivers, especially within the National Park and Lough Leane supports a wide variety of wintering waterfowl species e.g. Cormorant, Teal, Mallard, Pochard, Tufted Duck, Goldeneye and Coot, though all in relatively low numbers. A screening (Stage 1) for Appropriate Assessment of the discharges from the agglomeration was undertaken to assess, in view of best scientific knowledge and in view of the conservation objectives of the site, if the dischargess, individually or in combination with other plans or projects is/are likely to have a significant effect on the European Sites. 9

10 The screening assessment undertaken demonstrates that the discharges are likely to have significant effects, in terms of maintaining favourable conservation status of the qualifying interests, on the European Sites having regard to its conservation objectives. The main reason for this is because the plant is occasionally bypassed and discharges untreated effluent to the Folly Stream. The applicant determined that an Appropriate Assessment was required. The applicant submitted a Natura Impact Statement, as defined in Regulation 2(1) of the European Communities (Birds and Natural Habitats) Regulations 2011 (S.I. No. 477 of 2011). The Appropriate Assessment demonstrates that the discharges will not adversely affect the integrity of the European Sites. Any potential impacts are considered to be very minor in nature and the overall integrity of the Natura 2000 sites are not at risk from the Killarney WWTP. The assessment states that the plant will help improve the overall water quality of the lake. With regard to mitigation measures, the assessment states that the plant has the potential to be upgraded to further accommodate stormwater volumes, as listed in the County Kerry Wastewater Strategy document. The assessment notes that such upgrades are subject to funding coming onstream. Condition 5 of the RL, as drafted, requires an assessment of the waste water works, including the plant and storm water overflows, and the submission of a programme of works as appropriate to address any deficiencies. In accordance with the European Communities (Birds and Natural Habitats) Regulations 2011 (S.I. No. 477 of 2011), pursuant to Article 6(3) of the Habitats Directive, the discharge will not adversely affect the integrity, in terms of maintaining favourable conservation status of the qualifying interests of the European Sites, having regard to its conservation objectives. Environmental Liabilities Directive [2004/35/EC] Condition 7.2 of the RL satisfies the requirements of the Environmental Liabilities Directive in particular those requirements outlined in Article 3(1) and Annex III of 2004/35/EC. Environmental Impact Assessment Directive [85/337/EEC] An EIS and a copy of the planning approval was submitted in accordance with the Wastewater Discharge (Authorisation) Regulations In assessing the application regard was had to the matters mentioned therein in so far as they related to the risk of environmental pollution of the receiving water from the waste water discharge associated with this agglomeration. Should any further EIS be required as part of any programme of improvements, it will be dealt with as per Condition 1.8 of the RL. Cross Office Liaison Information relating to the Lough Leane monitoring programme and the status of Lough Leane was provided by Ms. Deirdre Tierney of the Office of Environmental Assessment. This information was incorporated into the assessment detailed above. Advice and guidance issued by the Technical Working Group (TWG) was followed in my assessment of this application. Advice and guidance issued by the TWG is 10

11 prepared through a detailed cross-office co-operative process, with the concerns of all sides taken into account. The Board of the Agency has endorsed the advice and guidance issued by the TWG for use by licensing Inspectors in the assessment of wastewater discharge licence applications. Submissions One submission was received in relation to this licence from Inland Fisheries Ireland, on the 20th April The main issues raised in the submissions are summarised below. Submission 1: Inland Fisheries Ireland Inland Fisheries Ireland submitted a letter issued by them to Kerry County Council and to the consulting engineers carrying out appropriate assessments on various WWTPs in County Kerry, including Killarney WWTP. The letter states that Killarney WWTP is subject to periodic overloading and bypass during storm flow conditions, which results in the discharge of inadequately treated effluent to Lough Leane. The letter also states that the Folly Stream is polluted by effluents which are not connected to the sewage network system. The letter does not identify the sources of this effluent. Response: The plant currently operates well below capacity and there is no evidence that the plant is being overloaded. In any case, Condition 5 requires an assessment of the effectiveness of the WWTP including the existing level of treatment provided by the plant and the capacity of the plant. To control storm water overflows, Condition 4.13 in conjunction with Condition 5 requires evaluation and upgrading of the storm water overflows to DoECLG standards by the 31 st December With regard to the discharge of effluent to the Folly Stream from sources not connected to the sewerage network, the RL as drafted prohibits any secondary discharges in the agglomeration. In addition, Condition 5 requires an assessment of the integrity of the waste water works having regard to any misconnections between foul sewers and surface water drainage networks. These measures, in combination with the ELV s set for the primary discharge, and the option to relocate the primary discharge point, will ensure that the receiving waters are protected. Site Visit I carried out a site visit was on the 12 th September The visit focussed on the treatment plant and the primary discharge outfall. No significant issues were noted during the visit. Charges The RL sets an annual charge for the agglomeration at 2, and is reflective of the monitoring and enforcement regime being proposed for the agglomeration. Recommendation 11

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13 Figure 1: Killarney Agglomeration D SW004 SW005 Lough Leane WWT SW003 SW002 River Flesk SW001 SW006 Folly Stream SW008 Ross Bay SW007 13