Proposed Student Accommodation at Punches Cross, Limerick City by Cloncaragh Ltd - Punches Cross Student ...
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Punches Cross Development, Limerick. Civil Engineering Report. 1
Civil Engineering Report
Proposed Student Accommodation at
Punches Cross, Limerick City
by Cloncaragh Ltd.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 2
Executive Summary
1. Introduction.
2. Existing Drainage & Watermain Services.
2.1 Existing Foul Water Drainage Networks.
2.2 Existing Surface Water Drainage Networks.
2.3 Existing Watermains Network.
3. Proposed Site Drainage & Water Supply.
3.1 Proposed Foul Water Drainage.
3.2 Proposed Surface Water Drainage.
3.3 Proposed Water Mains.
3.4 Comments by Water Services Dept in their submission to An Bord Pleanala.
4. Non-Technical Summary.
4.1 Stormwater & Foul Sewerage.
4.2 Predicted Impact of Development.
4.3 Remedial and Mitigation Measures.
4.4 References.
5. Construction methodology of the Development.
5.1 Demolition of the existing site buildings / clearance of entire site.
5.2 Basement Excavation.
5.3 Construction of Piles, Pile Caps, Ground Beams.
5.4 Construction of the Building Frame.
5.5 Building Envelope.
5.6 Building Fitout.
5.7 Site Enclosure.
5.8 Summary.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 3 1. INTRODUCTION The applicant, Cloncaragh Ltd, proposes to construct a new student accommodation complex including all associated facilities, underground carparking etc, at the junction of Ballinacurra Road and Rossbrien Road, Limerick City. This Civil Engineering Report addresses the design of the inground services necessary to service this proposed development, i.e. watermains, storm and foul sewerage services. This report also deals with the construction issues, construction methodology relating to the development. The development site extends to circa 0.78ha approximately. The site for several years was used as a vehicle / car, sales and repairs commercial premises. The site also operated for several years as a fuel filling station. The entire site has now been decommissioned and a detailed Closure Report for the entire site was prepared by URS Ireland Ltd, 410/411 Q House, 76 Furze Road, Sandyford, Dublin 18. This report by URS Ireland Ltd was completed 3rd September 2013. The site has remained unoccupied and disused for several years, circa 8 years. It remains secure with the site boundaries enclosed with metal fencing. The design of the inground services for this development, i.e. Watermains, Foul and Stormwater sewers was completed following a number of consultations with representatives from IRISH Water, and representatives from the water services department of Limerick City & County Council. The specific water services design criteria for new developments and as detailed in the Limerick City & County Council Development Plan was also referred to and has been complied with. It is further stated that the comments made by the Water Services Department of Limerick City & County Council in their submission to An Bord Pleanala; “Strategic Housing Development: Pre-Planning Consultation with An Bord Pleanála under Section 6 (9) of the Planning & Development (Housing) and Residential Tenancies Act 2016” has been complied with. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 4 2.0 Existing Drainage & Watermain Services. 2.1 Existing Foul Water Drainage Networks. The previous water services within this brownfield site, incorporating foul sewerage disposal have been totally decommissioned. This proposed development will incorporate new systems for the supply of fresh water and for the disposal of foul sewerage, surface water drainage from the site development and these are outlined and considered within this submission. Analysis of the existing council provided services within the surrounding area was undertaken to establish the capacity of the existing facilities, i.e. foul sewers, storm water sewers and water supply to service the development. A series of site visits were carried out on the neighbouring sites to observe the particular features of the area, including the construction of the new “LIDL” development on the southern end of the site. In addition, discussions were held with the Water Services Department of Limerick City & County Council where the effects of this proposed development would have on the existing council services were considered / discussed at length. Issues relating to the control of stormwater and foul water disposal from the developed site and as highlighted in the City & County Council Development plan were discussed at length. Consultations with representatives of Irish Water were also made to ascertain the impacts that this proposed development would have on Irish Water’s infrastructure. 2.2 Existing Surface Water Drainage Networks. The existing services, watermains foul sewerage network and the existing stormwater network within the site has been decommissioned. In discussions with the water services department of Limerick City & County Council the current situation where stormwater from the newly developed LIDL site (on the southern end of the site) and from sections of the Ballinacurra housing estate pass through an open drain within the Catholic Institute Tennis & Hockey Club was discussed. It was agreed that the surface water discharge from this proposed Student Accommodation development at Punches Cross, Limerick City by Cloncaragh Ltd would be discharged into the existing stormwater sewers located within the Ballinacurra road outside the site. This decision was founded on the historical data which showed that this open drain within the Catholic Institute’s grounds was subjected to storm surging and flooding following heavy rainfall events. The surface water from this new / proposed development would also be attenuated with a maximum discharge from the development limited to 4 litres / sec and the design based on a 1/100 year rainfall event, ( including allowing for Climate Change). 2.3 Existing Watermains Network. The existing watermains network within the site has been decommissioned. This proposed development incorporates a new approach to the installation of a watermains system within the site development and these are outlined and considered within this submission. A detailed topographical survey was carried out incorporating the development site and the surrounding roads. Where possible all existing manholes for sewers, (stormwater & foul) were accessed and levels taken. A full study of the commercial development on the “LIDL” site east of the development was taken and particularly where the development might impact on this proposed development. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 5
3.0 Proposed Site Drainage & Water Supply.
3.1 Proposed Foul Water Drainage.
The foul sewerage generated from the proposed development encompasses the following sections of the
site:
• Foul Waste from the toilets, showers, wash hand basins etc from both from the Bedroom Blocks
Buildings, separate independent apartments and the ancillary shops incorporated within the
development.
• Enclosed Bin Storage area incorporating bins / skips.
The foul sewerage network will consist of a sealed gravity system. It will service this development only. The
proposed new foul sewerage system will extend from within the development site and westwards to the side
of the site, (Ballinacurra Road). The details of this network layout are detailed in Drawing No’s:
18.104-1 Roof Downpipe & Ground Floor Level.
18.104-2 Basement Level – Storm & Foul Sewer Layout.
18.104-3 Ground Floor Level – Storm & Foul Sewer Layout.
18.104-4 Storm & Foul Sewer Longitudinal Sections.
It is proposed to discharge the foul sewerage within the basement section and the foul sewerage from the
ground floor and upper floors of the complete development in total into the existing Irish Water foul-sewer
located on the Ballinacurra Road. Refer to attached drawings.
It is proposed that all foul water from the proposed development will be collected on site via a series of
sewerage network pipes. A suitable grease trap will be installed to service all the ancillary commercial units’
washdown and deli areas, prior to discharge into the proposed new foul sewerage network. As per the
agreement with Irish Water the Basement sewerage will be pumped into the existing IW sewers on
Ballinacurra Road. Design guidelines from the EPA have been used to estimate the peak foul water loading
rates for both the student accommodation and ancillary commercial units within the development. The
relevant design approach / data relating to the design of the foul sewerage disposal from the site is as follows.
• 250 litres per person per day. (allowance includes waste from washing machines etc).
• Total Number of beds; 430#.
• Allowance of 1,500 litres per day foul sewerage waste from the ancillary shop units servicing the
development.
Estimated Foul Discharge Rate.
Dry Weather Flow (DWF) = 430 x 250 + 1,500 litres = 109,000 Litres / day or 1.26 litres/sec.
The estimated peak Flow is (3xDWF) = 3.78 ltrs/sec.
Included in the design approach to the design of the foul sewerage disposal on site is the recycling of roof
rainwater storage for the supply of water to the toilets in all the bedroom spaces.
The design of the foul sewerage systems servicing the proposed development has been assisted by the co-
operation of Irish Water and Limerick City & County Council engineers. The following as-built information was
provided to us by both Irish Water & Limerick City & County Council. Irish Water has confirmed their
acceptance of our design and this form of acceptance is attached with this submission.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 6
Schematic Layout of Foul & Stormwater sewers surrounding the Proposed Development Site.
(information supplied by Irish Water / Limerick City & County Council)
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 7 3.1.1 Water Conservation. Water conservation measures are included in the design of the foul sewerage systems for the development. All the stormwater from the roofs will be stored in storage tanks for later reuse in the supply of water to the toilets. This is dealt with further in the section dealing with the Stormwater design. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 8
3.2 Proposed Surface Water Drainage - Design.
As per the City & County Development plan the disposal of surface water from the proposed development
would be attenuated. In complying with the Council’s Development objectives, the following design criteria
would be adopted.
- The surface water pipe network within the development would be designed to cater for 1/5 & 1/30 year
rainfall return periods.
- Stormwater Attenuation would be incorporated within the design, whereby the stormwater from the
development would be attenuated based on a rainfall return period, 1/100 years. The rate of discharge
from the site following a rainfall 1/100 period return event would be 4 litres / sec maximum discharge.
This rate of discharge was agreed with the water services department of Limerick City & County Council.
- The attenuated surface water is to be stored within two large concrete storage tanks to be located within
the basement area. The necessity for two storage tanks is due to the ground floor slab levels having a
finished floor level varying from 15.2m to 14.4m. Each attenuation tank will have a floor control device,
the accumulation of both will not exceed 4 litres / sec.
- The attenuated stormwater would be discharged by gravity into the existing stormwater sewers within
the Ballinacurra Road, (all as detailed on the accompanying drawings - 18.104-3.)
- The stormwater generated within the basement shall be stored within an inground storage tank,
“StormBloc” cells and pumped periodically up into the attenuation storage tanks. All basement generated
stormwater will flow through a Class 1 oil interceptor prior to discharge into the storage tanks etc.
- As a means of complying with the SUDS requirements, “Sustainable Urban Drainage Systems” all
rainwater from the roof areas will be discharged into storage tanks with this water used for toilets, wash
down areas etc.
The stormwater from the proposed development has been designed in accordance with Limerick City &
County Council Development Plan and the City of Dublin Sustainable Drainage Systems, (CDSDS) and
ensures the best management practice has been incorporated into the design. The disposal of storm water
from site will be managed in two distinct ways. The design approach / intent is to ensure that the disposal of
storm water from the developed site will equate to the disposal of storm water from the existing undeveloped
brownfield site. In addition, all rainwater from the roofs of the buildings will be stored in storage tanks for
reuse in all the toilets within the development. This approach will assist greatly in minimising the use of fresh
water from the council mains.
Rainwater Harvesting – Rainwater storage sourced from the Roof Areas - The storm water from the roofs of
the buildings and the courtyards will be fed directly into specially designed storage tanks located within the
basement. All rainwater will be harvested and used to supply water to operate the skip / bin-wash facility,
irrigate the grass areas within the courtyards and supply water to the toilet cisterns within all the bedroom
blocks. Both operations will operate as closed systems. All excess water from the roofs and courtyards will
be discharged into the development’s storm water system attenuation tanks located within the basement.
The recycling of rainwater to service the toilets within the complex, in addition to providing water to irrigate
the plants and green areas generally within the internal courtyard will contribute significantly in the reduction
of the development’s usage of fresh potable water used onsite.
Attenuation of Stormwater from the internal courtyard, the Basement Car Parking Area, Roadway Entrance,
building’s Roof Areas - surface water from within the basement car parking area, roadway entrances, internal
courtyard areas and excess rainwater from the roofs of the buildings will be fed via Class 1 silt traps and Full
Retention interceptors into the storm water attenuation storage areas to be located with the basement. The
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 9
storm water attenuation area will be sized to ensure that the maximum storm water discharge from the site
will equate to that of the undeveloped brownfield site. The following design values will be incorporated within
the design.
• Rainfall Historical Data sourced from Met Eireann for the Limerick City Region, (Punches Cross).
• Rainfall Attenuation Design; Rainfall Return Period: 1/100 years + 20% capacity for Climate change.
• Design of the stormwater sewer pipework; Rainfall Return Period; 1/5 years and 1/30 year for storm
surge in pipework.
• Rainwater from the roof areas, internal courtyard and basement carpark to be collected and stored
in underground storage tanks to be re-used as water supplies to service the facility’s toilets, courtyard
irrigation and cleaning of bin / skip-yard.
Design Principles of the Storm Water Attenuation System.
From a surface water design aspect, the entire site area is considered to consist of an impermeable surface
finish. As such, the quantities of stormwater discharging from site is to be considered to be greater than that
from a similarly sized greenfield / brownfield site. The total developed site area is approximately 7,600m2.
As per the Site Flood Report by JBA Consulting, the site is not subject to flooding or ground water issues.
The design approach is to consider those areas where stormwater is generated, and which needs to be
discharged into the storm water network. As a means of minimising the flow of stormwater from the
development site into the existing council storm drain located on the Ballinacurra Road, it is proposed to
install 2# stormwater attenuation tanks and surface water control flow devices attached to each attenuation
tank. The maximum stormwater permitted into the Ballinacurra Road stormwater sewer is limited to the
quantity of surface water expected to be generated within an undeveloped greenfield / brownfield site. As per
the Limerick City & County Council Development Plan, the discharge of stormwater from the developed site
is restricted to 4litres/second per Hectare. An additional 20% spare capacity is allowed for to cater for climate
change.
The water conservation measures, the storing and re-cycling of grey water from the roof areas within the
development are excluded from this design assessment.
The design procedure developed by the UK Institute of Hydrology is also adopted to quantity the permitted
outflow. The following calculations are based on the research and published documentation from the Institute
of Hydrology of the UK, Report No.124.
0.89 1.17 2.17
QBAR = 0.00108 x (Area) (SAAR) (Soil)
Where QBAR (m³/sec) is the mean peak flow, Area (km²) is the catchment, SAAR (mm) is the standard
Annual Average Rainfall and is a soil index with values in the range 0.15 – 0.5
Proposed Development Site Area: 6,200m²
Soil Index: 0.42
SAAR: 820mm
QBAR = 4.1 Litres/sec.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 10 However, using the guidance from the Limerick City & County Council Development Plan a QBAR discharge of 4 litres/sec will be adopted. It is proposed to allow the discharge of 4 litres /sec into the existing open drains by attenuating the storm water generated from the development. The volume of storm water generated is based on a rainfall return period of 1/100 years, all storm data taken from Met Eireann published records. The “Hydrobreak” rainwater control device will be located downstream of the attenuation tanks. Two stormwater storage tanks are proposed. These Tanks will be located within the basement. Two are required so as to cater for the variation in the suspended ground floor levels (in excess of 1.2m) and to ensure that the stormwater discharge from the southern end of the site can be discharged into the storage tanks provided. The overall impermeable developed site area is circa 6,200m2. Each Attenuation Tank will have a Hydrobreak flow control valve located downstream of the flow which will limit the flows from the tanks, i.e. Tank A: 2.5 lts/sec, Tank B: 1.5 lts/sec. Stormwater Tank A will cover a site area of approximately 3,400m2. In addition, this stormwater storage Tank will accommodate the pumped water from the inground basement tank (60m3), which will cater for the surface water within the enclosed basement and the water generated from a car fire event, and / or where the watermains for the development need to be flushed out etc. In summary, storage Tank A: Capacity: 300m3. This tank is located at the northern corner of the site adjacent to the junction of Ballinacurra Road and Rossbrien Road. Storage Tank B: Capacity: 190m3. This tank is located at the western corner of the site on the Ballinacurra Road. All stormwater from the development will pass through Class 1 Full Retention Petrol interceptors prior to entering into the storage tanks. Each of the storage tanks, A & B will be connected to a Hydrobreak value downstream of the tank which will control the flow of stormwater from the development. The need to provide two individual “Hydro-break” control valves is to ensure that all stormwater flow from the development is controlled prior to leaving the site and discharging into the council mains. In addition to the 2# stormwater attenuation storage tanks, an inground water storage tank is proposed for the basement. This water storage tank is to cater for the discharge of surface water from within the basement and from the basement ramp areas Furthermore, this inground basement storage tank is designed to cater for the storage of water which would be generated in the event of a car fire within the basement and or where the water within the watermains for the development needs to be flushed out. All basement surface water will enter the inground water storage tank via a Class 1 full retention petrol interceptor. The size of the inground stormwater storage tank is 5.5m x 16.5m x 0.6m deep = 60m3. This storage volume is sufficiently sized to cater for the water storage capacity of two fire engines, (circa 25m 3 of water) in addition to the discharge of any stormwater from within the basement surface. The treated / filtered & stored groundwater will be periodically pumped up into the Stormwater storage Tank A for ultimate controlled discharge into the council mains on Ballinacurra Road. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 11
Stormwater Tank A.
STORAGE VOLUME.
Pump-out rate from system = 2.5 litres/sec.
100 Year Storm Event.
Storm Av. Total Imp. Area Total Run Empty Amount Storage
Duration Rainfall Rainfall Off Rate Per Emptied Volume
Intensity 100 Years Day over Storm Req’d
Period
days mins mm/hr mm ha m3 m3/d m3 m3
0.003 5 217 18.1 0.34 62 345 0.75 62
0.007 10 151 25.2 0.34 86 345 1.50 85
0.010 15 119 29.7 0.34 101 345 2.25 99
0.021 30 69 34.7 0.34 118 345 4.50 114
0.042 60 41 40.5 0.34 138 345 9.00 129
0.083 120 24 47.4 0.34 161 345 18.00 153
0.167 240 14 55.3 0.34 188 345 36.00 152
0.250 360 10 60.6 0.34 206 345 54.00 151
0.500 720 6 70.8 0.34 241 345 108.00 133
1.000 1440 4 82.7 0.34 281 345 216.00 65
2.000 2880 2 92.1 0.34 315 345 432.00 -
Amount of Storage required for stormwater generated: 152m³ + 20% for Climate Change.
Total Storage Volume required = 152m3 + 31m3 = 183m3
In-addition, the total basement stormwater storage capacity is added to Tank A. The resultant storage
capacity of Tank A: = 183m3 + 60m3 = 243m3. A Storage Tank of 300m3 is provided.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 12
Stormwater Tank B.
STORAGE VOLUME.
Pump-out rate from system = 1.5 litres/sec.
100 Year Storm Event.
Storm Av. Total Imp. Area Total Run Empty Amount Storage
Duration Rainfall Rainfall Off Rate Per Emptied Volume
Intensity 100 Years Day over Storm Req’d
Period
days mins mm/hr mm ha m3 m3/d m3 m3
0.003 5 217 18.1 0.28 50 130 0.45 50
0.007 10 151 25.2 0.28 71 130 0.90 70
0.010 15 119 29.7 0.28 83 130 1.35 82
0.021 30 69 34.7 0.28 97 130 1.70 95
0.042 60 41 40.5 0.28 113 130 3.40 110
0.083 120 24 47.4 0.28 133 130 6.80 126
0.167 240 14 55.3 0.28 155 130 13.60 141
0.250 360 10 60.6 0.28 170 130 27.20 143
0.500 720 6 70.8 0.28 198 130 54.40 144
1.000 1440 4 82.7 0.28 232 130 108.40 124
2.000 2880 2 92.1 0.28 258 130 116.80 142
Amount of Storage required for stormwater generated: 143m³ + 20% for Climate Change.
Total Storage Volume required = 143m3 + 30m3 = 173m3. A Storage Tank of 190m3 is provided.
The above stormwater attenuation design guarantees that the surface water discharge from the site will not
exceed 4litres/second over a rainfall event equivalent to a 1/ 100 rainfall return period.
Notes:
To be read in conjunction with
1. Drawing No: 18.104-1Roof Downpipe & Ground Floor level Stormwater Drainage Layout.
18104-2 Basement Level – Storm & Foul Sewer Layout.
18104-3 Ground Floor Level – Storm & Foul Sewer Layout.
18104-10 Schematic Map illustrating areas covered by each Storage tank.
2. Rainfall data for 100-year storm from Met Eireann Office Records for Limerick City.
3. Max discharge from system to be regulated by Hydrobreak flow control device.
4. Benefits from water conservation measures are excluded from calculations.
5. Benefits from the percolation / filtration of the stored water through the base of the basement tank
construction area is ignored.
6. 100% of site area is considered as impermeable.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 13 Design of Stormwater Pipework. (Refer to drawing 18.104 – 3 & Design Sheet & attached schematic 181-104-10) The stormwater network of pipework servicing the disposal of the stormwater generated within the development from ground floor upwards will be suspended beneath the ground floor slab, (within the basement) and will direct all the stormwater from the development into the stormwater attenuation tanks. These stormwater pipes are all sized to cater for a 1/30-year storm event as per the Limerick City & County Development Plan. Attached are the details of the design. The rainfall data is sourced from Met Eireann. The storm sewers in the basement are designed to specifically remove the rainwater from the access and exit ramps, the water from a fire engine truck, (in case of fire) and to cater when the water in the watermains has to be washed out etc. These sewers consist of 300mm diameter uPVC sewers and are totally capable of accommodating the surge flows. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 14 The layout of the stormwater sewers fixed to the underside of the ground floor concrete slab. This layout is to be read in conjunction with the sewer spread sheet attached. DWG; 18.104-10 Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 15
Met Eireann.
Return Period Rainfall Depths for sliding Durations Irish Grid: Easting: 156998, Northing: 155581, - Punches Cross Development.
Interval | Years
DURATION 6months, 1year, | 2, 3, 4, 5, 10, 20, 30, 50, 75, 100, 150, 200, 250, 500,
5 mins 2.7, 3.9, | 4.6, 5.6, 6.4, 6.9, 8.8, 11.1, 12.6, 14.7, 16.6, 18.1, 20.5, 22.3, 23.9, N/A ,
10 mins 3.7, 5.4, | 6.4, 7.9, 8.9, 9.7, 12.3, 15.4, 17.5, 20.5, 23.1, 25.2, 28.5, 31.1, 33.3, N/A ,
15 mins 4.3, 6.4, | 7.5, 9.3, 10.4, 11.4, 14.5, 18.1, 20.6, 24.1, 27.2, 29.7, 33.6, 36.6, 39.1, N/A ,
30 mins 5.6, 8.1, | 9.5, 11.5, 12.9, 14.0, 17.6, 21.7, 24.5, 28.4, 32.0, 34.7, 39.0, 42.3, 45.0, N/A ,
1 hours 7.3, 10.3, | 11.9, 14.3, 15.9, 17.2, 21.4, 26.1, 29.2, 33.6, 37.5, 40.5, 45.2, 48.8, 51.9, N/A ,
2 hours 9.4, 13.0, | 14.9, 17.8, 19.7, 21.2, 25.9, 31.3, 34.8, 39.7, 44.0, 47.4, 52.5, 56.4, 59.7, N/A ,
3 hours 11.0, 15.0, | 17.1, 20.2, 22.3, 23.9, 29.0, 34.8, 38.5, 43.8, 48.3, 51.9, 57.2, 61.4, 64.8, N/A ,
4 hours 12.2, 16.5, | 18.8, 22.1, 24.3, 26.0, 31.5, 37.5, 41.4, 46.9, 51.7, 55.3, 60.9, 65.2, 68.7, N/A ,
6 hours 14.2, 19.0, | 21.5, 25.1, 27.5, 29.4, 35.3, 41.7, 45.9, 51.7, 56.7, 60.6, 66.4, 70.9, 74.6, N/A ,
9 hours 16.5, 21.8, | 24.5, 28.5, 31.1, 33.1, 39.5, 46.4, 50.9, 57.0, 62.3, 66.4, 72.5, 77.2, 81.0, N/A ,
12 hours 18.4, 24.1, | 27.0, 31.2, 34.0, 36.1, 42.8, 50.1, 54.7, 61.1, 66.6, 70.8, 77.1, 81.9, 85.9, N/A ,
18 hours 21.4, 27.7, | 30.8, 35.4, 38.5, 40.7, 47.9, 55.7, 60.6, 67.3, 73.1, 77.5, 84.1, 89.2, 93.3, N/A ,
24 hours 23.8, 30.5, | 33.9, 38.8, 42.0, 44.4, 51.9, 60.0, 65.2, 72.1, 78.1, 82.7, 89.5, 94.7, 98.9, 113.1,
2 Days 30.5, 38.0, | 41.8, 47.0, 50.5, 53.0, 61.0, 69.3, 74.6, 81.6, 87.6, 92.1, 98.9, 103.9, 108.0, 121.7,
3 Days 36.3, 44.6, | 48.6, 54.3, 57.9, 60.6, 69.0, 77.7, 83.2, 90.4, 96.6, 101.2, 108.0, 113.1, 117.2, 131.0,
4 Days 41.6, 50.5, | 54.9, 60.9, 64.7, 67.6, 76.4, 85.5, 91.1, 98.6, 104.9, 109.6, 116.6, 121.7, 125.9, 139.8,
6 Days 51.5, 61.5, | 66.3, 73.0, 77.2, 80.3, 89.8, 99.6, 105.5, 113.5, 120.1, 125.0, 132.3, 137.7, 142.0, 156.3,
8 Days 60.8, 71.7, | 76.9, 84.1, 88.7, 92.0, 102.1, 112.5, 118.8, 127.1, 134.0, 139.1, 146.7, 152.2, 156.7, 171.4,
10 Days 69.6, 81.4, | 87.0, 94.7, 99.5, 103.0, 113.7, 124.6, 131.2, 139.8, 147.0, 152.4, 160.1, 165.9, 170.5, 185.6,
12 Days 78.1, 90.7, | 96.7, 104.8, 109.8, 113.6, 124.8, 136.1, 143.0, 152.0, 159.4, 164.9, 172.9, 178.8, 183.6, 199.0,
16 Days 94.6, 108.7, | 115.2, 124.1, 129.6, 133.7, 145.8, 158.0, 165.3, 174.9, 182.8, 188.6, 197.0, 203.2, 208.2, 224.3,
20 Days 110.7, 125.9, | 133.0, 142.6, 148.5, 152.8, 165.8, 178.7, 186.4, 196.5, 204.8, 210.9, 219.7, 226.2, 231.3, 248.0,
25 Days 130.3, 147.0, | 154.6, 164.9, 171.3, 176.0, 189.8, 203.5, 211.7, 222.3, 231.0, 237.4, 246.6, 253.4, 258.7, 276.1,
NOTES:
N/A Data not available
These values are derived from a Depth Duration Frequency (DDF) Model For details refer to:
’Fitzgerald D. L. (2007), Estimates of Point Rainfall Frequencies, Technical Note No. 61, Met Eireann, Dublin’,
Available for download at www.met.ie/climate/dataproducts/Estimation-of-Point-Rainfall-Frequencies_TN61.pdf
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 16 Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 17
Flooding.
All matters relating to flood risk with this development site are dealt with separately by JBA
Consulting on separate cover. However, referencing the flooding potential for the site and as
prepared by JBA Consulting it can be seen that the site is well positioned above the nearest flood
risk area and is not at risk of any possible site flooding due to weather events. The latest flood maps
available from the website www.floodinfo.ie shows that the proposed development site is
significantly away from the nearest flood potential lands.
Extract from floodinfo.ie detailing the nearest potential flood areas
in and around the location of the proposed development.
Proposed Development site shaded in Red.
Flood Risk Lands identified in floodinfo.ie
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 18
Basement Stormwater storage system.
The design details as presented by “Stormbloc” show the Modular Units being built up within the basement
ground and overlay a geotextile separation layer. As such, a storage volume, 5.5m x 18.2m x 0.6m deep =
100m3 is available for basement surface water storage. The additional form of surface water removal, by
filtration is excluded in the design calculations due to the design basement depth and the current
inaccessibility to carry out filtration tests on this ground level.
Note, all surface water entering the basement storage tank enters via a Class 1 full retention separator.
The purpose of the basement stormwater storage tank is to cater for a number of scenarios;
• Removal of the surface water runoff from the access roads into the basement carpark,
• Removal of the water from the flushing out of the watermains servicing the development located
within the basement.
• Removal of the water used by the fire brigade in the event of a car fire within the basement.
The basement water storage tank has been sized to cater for these events. The surface water from the
basement storage tank flows by gravity to a “Klargester” sump and the water is pumped up into the
stormwater storage Tank A for storage and controlled discharge into the public stormwater pipe.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 19 Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 20
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Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 21 Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 22 3.3 Proposed Watermains An existing 300mm diameter Watermain runs along the Ballinacurra Road adjacent to the site which will be used to provide water to the site. This watermain is in the ownership of Irish Water and the details of this watermain is provided on a drawing attached to the appendix. (Refer to Drawing 18104-5A) It is proposed to extend a 150mm diameter watermains into the development. A single bulk. “pulse” type water meter will be fitted onto the watermains network to measure all freshwater entering the development. An internal fire mains and block rising fire mains will be installed to service the development all as per Part B Technical Guidance Document of the Building Regulations. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 23
Schematic of existing Watermains as supplied by Limerick City & County Council / Irish Water.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 24
3.4 Comments made by the Water Services Department of Limerick City & County Council in their
submission to An Bord Pleanála; “Strategic Housing Development: Pre-Planning
Consultation with An Bord Pleanála under Section 6 (9) of the Planning & Development
(Housing) and Residential Tenancies Act 2016”.
The comments by the Water Services Dept in relation to this development related to the necessity for the
following.
a) Hydraulic Modelling for the design of pipes at a 1/5 year, return period.
b) Hydraulic Modelling for the design of the network at a 1/30 year, return period.
c) Hydraulic Modelling for the network design for a 1/100 year, return period with no flooding in
accordance with the development plan.
d) Design of surface water drainage from proposed development onto the Rossbrien Road towards
Childers Road should be designed to accommodate the surface water runoff generated by the
Rossbrien road.
e) Structural surveys of surrounding properties on the Rossbrien Road will be required due to the 6m
depth of excavation required for sewers.
The queries raised by the Water Services Department have been completely addressed and we state the
following.
Items a – c.
The stormwater pipework / network has been designed to cater for a 1/5 & 1/30 year, storm event. In addition,
the stormwater system has been designed to cater for a 1/100 year, rainfall event to ensure that no flooding
of the development can occur due to such adverse weather events.
Item d.
All attenuated surface water from the development discharges into the council’s stormwater sewers located
on the Ballinacurra road only.
Item e.
No inground services servicing the development will be located within the Rossbrien Roadway and
connecting into the Childers Road. The roadworks required to be carried out on the Rossbrien Road adjoining
the development site will be localised, consisting of sewers of shallow depth, electrical / gas services etc
which will also be laid at shallow depths. As such it is not envisaged that structural surveys will be necessary
on the Rossbrien Road due to the development etc.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 25
4.0 Non – Technical Summary.
4.1 STORMWATER & FOUL SEWERAGE.
The approach taken in the design of the disposal of the foul sewerage and surface water generated on the
developed site is to ensure that the proposed complies with the Limerick City & County Council Development
plan. In this regard it has been essential to demonstrate to both Irish Water & Limerick City & County Council
that gravity sewer mains (Stormwater & Foul Sewerage separate systems) servicing the development can be
constructed and connected to the existing mains systems (and subject to planning permission) and in such
a manner which will allow for sustainable development in accordance with the City & County Development
plan etc. Furthermore, it has been possible to obtain data on the existing inground services under the
ownership and control of Irish Water / Limerick City & County Council which has allowed us to develop our
design in a practical way.
It has also been established that the development and the surface water and foul sewerage discharges from
the development will be free from any effects of flooding events due to the site being located on a level
considerably higher than the flood zones mapped and identified within the Flood Report by JBA Consulting.
The following key design factors have also been considered and allowed for in the developed site surface
water and foul sewerage disposal design process;
i. Allowance in the stormwater disposal design to cater for a rainfall return event of 1 in 100-year rainfall
event including an allowance for Climate Change.
ii. Ensure that the surface water discharging from the developed site is controlled such that the rate of
disposal of stormwater from the developed site is in accordance with the Limerick City & County
Council Development Plan, i.e. 4 litres per second.
iii. Ensure that the surface water discharging from the developed site passes through full retention class
1 oil interceptors prior to discharge from the site.
iv. Ensure that the pathway for the discharged stormwater is well defined and that the resultant
development does not cause or result in a flood risk to adjoining lands, developed or otherwise.
v. Ensure that only the surface water from “clean areas” within the developed site, discharge into the
stormwater discharge system and that the stormwater from any contaminated areas of the site, waste
bin locations discharge into the site sewers.
vi. Ensure that all the rainwater from the roofs of the Buildings are channelled into storage attenuation
storage tanks. The stored rainwater is to be used to service the toilets in all blocks and for irrigating
the green areas within the courtyard. The used water is in turn to be re-cycled where possible to
allow the system to be as efficient as possible.
vii Inspection manholes will be constructed throughout the site to allow for periodic sampling of the
waste waters from the development to ensure that all waste water is within the limits set by Irish
Water.
viii The storm sewers within the development have been designed to cater for 1/30 year storm events
and in accordance with the County Development plan.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 26
4.2 PREDICTED IMPACT OF DEVELOPMENT
Waste Water
The applicant is seeking permission from Irish Water to discharge 1.26 / 3.78 litres/sec (peak) into the Irish
Water controlled foul sewer. The proposed development will adhere to this limit. The development will also
adhere to the limits of the organic loading as detailed in the Irish Water Pre-Connection Enquiry Form. It can
be stated that existing public foul sewer system has adequate capacity available to cater for the proposed
development.
Storm Water
The applicant is seeking consent to discharge 4 litres/sec of Stormwater to Limerick City & County Council
stormwater sewer. A new storm sewer system is proposed to service the development.
The stormwater system will incorporate attenuation areas, Class 1 silt traps, hydrocarbon interceptors and
two hydro-brake control valves at the outfall to control storm water flow from the site.
Storm water from roof areas will be collected within underground storage tanks which will supply water to the
building toilets & irrigation areas within the courtyard. Excess storm water from the rain harvesting system
will be discharged to the site’s storm water drainage system.
The potential impact on surface water during operation is considered to have a long term, imperceptible
impact, with a Neutral impact on quality i.e. an impact capable of measurement but without noticeable
consequences.
Water Supply
There is no large usage of water for process purposes. The water supply to the site will be required for the
following purposes;
• Supply of potable water to the complex.
• Top-up supply to the underground water storage tanks servicing the toilets only where necessary.
• Fire Fighting purposes. Fire Hydrants will be provided within the development.
The average water demand for the development has been calculated as being 1.24 litres / sec.
4.3 REMEDIAL AND MITIGATION MEASURES
The design of the proposed development has taken account of the potential impacts of the development and
the risks to water services and in particular storm water. There are no existing active services within the site
as the site has been decommissioned.
Mitigation measures will be implemented to protect the local environment from potential effects on water
services. These measures seek to avoid or minimise potential effects in the main through the implementation
of best practice construction methods and adherence to all relevant legislation.
Waste Water
The foul system will collect all sewerage which will be discharged directly to the Irish Water Sewers as
detailed.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 27 Surface Water There will be no un-mitigated discharges to the surface water environments as all surface water will be collected by the proposed storm water system. It will be necessary to periodically visually check the hydrocarbon interceptors for excessive build-up of hydrocarbons and the attenuation tank for signs of contamination which should be included in a maintenance programme. Water Supply It is understood that there is adequate water supply within the Irish Water Network to service the site. 4.4 REFERENCES Met Eireann Rainfall Historical Data for the Limerick Region Details of Open Drains under the control of the Office of Public Works, (OPW) Geophysical Survey Drawing prepared by “Townland Surveys” Groundwater Data from flooding consultants “JBA Consulting” Estimation of surface water discharge and flows from Wallingford Research Laboratories Institute of Hydrology of the UK. Decommissioning Report by URS Ireland Ltd. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 28
5. Construction Methodology of the Development.
5.1 DEMOLITION OF THE EXISTING SITE BUILDINGS / CLEARANCE OF ENTIRE SITE.
The existing buildings consist of single storey
above ground units and a singular deep
basement. The roof of the building units contain a
mixture of tar coverings, asbestos sheeting and
corrugated metal cladding. The dilapidation
survey will quantify the full extent of the presence
of the asbestos sheeting etc on site.
Any asbestos containing materials identified on
site will be removed and disposed of in
accordance with statutory “Exposure to Asbestos”
Health and Safety Regulations. The demolition
process will be such to carefully remove &
individual wrap the asbestos roof sheeting panels
etc. Detailed method statements will need to be prepared and put in place to ensure that any and all asbestos
identified on site is both carefully handled by an approved asbestos contractor and disposed of in full
compliance with the statutory “Exposure to Asbestos” Health and Safety regulations.
The remaining demolition works will incorporate the careful dismantling of the commercial units, followed by
the demolition of the basement section of the building.
5.1.1 THE MONITORING OF NOISE, VIBRATIONS, DUST GENERATED DURING THE DEMOLITION
STAGE.
Noise levels will be continuously monitored. All noise monitoring and control will be to;
• BS 5228:2009 Code of Practice for Noise Control & Vibration Control on construction & Open Sites.
• Safety, Health & Welfare at work (construction) Regulations 2013,
• BS 6187: 2011 – Code of Practice for full & Partial Demolition.
• Environmental Protection Agency Act 1992,
• BS 4142: 2014 Methods for rating and assessing industrial & Commercial sound.
• Exposure to Asbestos” Health and Safety Regulations.
The Vibration monitoring will be carried out in accordance with BS 5228-1, 2009, Code of Practice for Noise
& Vibration Control on Construction & Open Sites.
The limitations and standards of vibration & noise control will also adhere to the British Standards
specifications on Vibration & Groundwater Monitoring. The control of dust which is generated during the
munching and concrete saw cutting is critical to ensuring that there will be no Health & Safety incidents during
this demolition phase. Consequentially, appropriate Air Quality & Dust monitoring will be carried out on a
regular basis in accordance with Limerick City & County Council planning conditions. A full set of records will
be kept on site of all monitoring on site for review by the Planning Authority.
On a site as restricted at this site at Punches Cross which abuts significant road traffic networks and business
operations, it is imperative that pollutants such as noise, dust and vibrations are properly controlled.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 29
Vibration monitors will be strategically placed in the area of demolition operations, which will record locally
and notify automatically if limits are breached. These monitors will be one or a combination of;
• Reflective prisms (Total Stations)
• Inclinometer,
• Tiltmeter,
• Stud and precise level monitoring.
These monitors are to be capable of tracking vibration emanating from the demolition operation and recorded.
The monitors need to be set to trigger an alert should an agreed “ceiling” limit be breached by the works.
Dust Deposition Gauge.
In relation to dust monitoring, which will be a potential risk during the bulk
excavation & foundation construction part of the works, the developer /
contractor will use dust deposition gauges or measurement devices such as
the one pictured in figure over. These can be measured on a weekly or even
daily basis and based on the levels monitored, additional dust suppression
systems such as spraying or misting can be utilized if necessary.
The developer will manage the control of dust and dirt on site by the following.
• The use of screens and dust sheets to be utilized where required to
minimize the nuisance caused by dust. These will be primarily placed
along the east elevation at the boundary of the site and along all the
other boundaries to prevent the spreading by the air of the dust.
• Debris netting will be placed on the scaffolding of all the
superstructure scaffolds where necessary.
• All rubbish skips will be fitted with nets during windy conditions to prevent rubbish and debris blowing
over the site into adjoining properties. Skips will be promptly removed from site when full.
• The Punches Cross building site will be inspected daily and the condition closely monitored. The
results of these inspections along with the nature of works on-going on the site at the time will dictate
the extent of road cleaning required. A road sweeper will be utilized at all times during the course of
the demolition and construction stages to ensure that the roadways are always clean and free of
construction waste.
• A wheel wash facility will be provided for the duration of the works (power washer).
• Mini skips will be used to remove debris from each floor of each building to strategically located skips
below.
The developer will always operate a clean as you go policy.
More detailed / job specific method statements detailing the containment of dust and dirt will be developed
and utilised as part of the developer’s / Main Contractors Waste Management Plan / Construction Waste
Management Plan prior to the commencement of the development etc..
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 30
Typical Road Sweeper to be used to maintain the roadways clear of site dirt.
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 31 5.2 BASEMENT EXCAVATION. (REFER TO DRAWING 18.104-11) The extent of the Bulk Excavations shall generally be as per the attached drawing. Temporary and propped interlocking Steel Sheet Piles will be installed along the boundary of the proposed basement profile. The sheet pile installation will allow for a safe working setup within the site while also providing stability to the boundary footpaths / council services etc. Access to the basement is via the Rossbrien road entrance while the site exit will be via the Ballinacurra Road entrance. The site will operate a one-way traffic flow, with site entrance and exit as per the attached. A full truck wheel wash facility will be positioned and operated at the exit ramp as shown. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
Punches Cross Development, Limerick. Civil Engineering Report. 32
Drawing No: 18.104-11
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 33
Site Safety procedures required during the Basement Excavation.
The site entrance and exit will be manned to ensure that the site traffic, (pedestrian & vehicular) can safely
enter and exit the site. The provision of the site security will also ensure the prevention of unauthorised entry
etc. A traffic management plan will be prepared and agreed with the Traffic Department of Limerick City &
County Council all as per conditions of planning. Issues such as the manner in which construction workers
will travel to and from work, the management and flow of trucks to and from the site and the management of
deliveries of materials to the construction site will be thoroughly planned, managed etc.
Due to the location of the development there are many restrictions which need to be considered in the
planning and management of vehicular traffic to and from the development. It is envisaged that consultations
with the adjoining householders / businesses will be required to ensure that the adjoining site owners /
occupiers and their operations, (particularly the operation of public vehicular traffic) will not be interfered with
during any of the construction stages of the development. Care will be taken to illustrate clearly the
methodology which the contractor / developer will utilise to construct this project activity while also ensuring
the safe and continuous operation of the adjoining businesses and operations. The Construction
Management & Waste Management Plans much include these operations in its documents.
Water Pollution Site Control Measures.
Water pollution generated from construction activities usually occur as a result of the release of silt / sediment
or spillage of hazardous substances. To prevent such impacts on ground water, control measures will be
implemented from the commencement of site activities and maintained for the duration of the construction
period. Procedures for surface water control (often referred to as erosion and sediment control) to minimise
release of sediment to waterways will be established and continuously monitored to ensure that there is no
pollution due to the site activities.
Sediment control measures will be designed and implemented to prevent the transport of sediment and other
pollutants into rivers etc, either by providing a physical barrier (filtering) or by slowing the flow rate of water
so that the suspended pollutants “drop out” (settling). Filtering measures include sediment filters, whilst
settling measures include sediment tanks. The type and capacity of control measure required is dependent
on a variety of factors, including the volume and duration of flow, and the particle size of the sediment. Fine
sediments (clays and slits) are harder to remove as they will take longer to settle than coarse sediments
(sands and gravels).
Surface Water Sedimentation Tanks.
The control of ground water and water within deep excavations is a major issue both from a working and
environmental perspective.
Typical
Sedimentation
Tanks
Pierce McGann & Company,
Consulting Civil I Structural Engineers
22 Barrington Street, Limerick. (Rev May 19)Punches Cross Development, Limerick. Civil Engineering Report. 34 Under a variety of national and EU laws, it is an offence to knowingly pollute subsurface water, and all efforts will be made to avoid any impacts on this resource. Impacts on groundwater generally occur as a result of the infiltration of polluting substances through the surface and subsurface soils as well as the transfer of pollutants from surface watercourses. The developer will produce procedures and site-specific methodologies to ensure that the surface water from this construction site is dealt with in such a manner that the pollution of waterways and rivers, sewerage systems are prevented. The Developer will liaise with Limerick City & County Council and seek a licence for the discharge of treated ground water from the site. The site-specific groundwater filtration system will be designed and agreed with Limerick City & County Council prior to any excavation works for the Basement structure. In the case of this development it will be necessary to install a tank, usually containing a number of separate chambers, allowing sediment to settle out of the groundwater. These are most effective when treating low flows and coarser sediments, although a flocculant may be used to assist the settlement of finer material. A number of tanks may be used together to increase capacity. It is envisaged that these settlement / filtration tanks will be located within the space of the large attenuation tank area. Wheel Wash Facility. A wheel wash facility will be located at the exit roadway from the site. This wheel wash facility will be strategically placed so as to ensure that the wheels of all trucks and plant transport vehicle are thoroughly clear prior to leaving the site and onto the public roadway. The wheel wash will have appropriate signage directing it to be used by vehicles exiting the site. In addition, the developer will constantly monitor the local road and ensuring on the daily attendance of road sweep vehicles to ensure that no construction dirt leaves the site and onto the public roadway. The waste from the wheel wash will be connected directly to the site stormwater sedimentation tanks to ensure that all waste water is collected and properly filtered and tested to ensure that no contaminated water leaves the site. Concrete Wash Out Area. In addition to the wheel wash a a concrete wash out area will be installed. This wash out area will service the cleaning out of concrete Ready-Mix vehicles. The waste from this area will be linked to the sediment tanks to prevent contaminated water leaving the site. Surface water Attenuation. The entire process of the control and treatment of the surface water from the construction site and during all the stages of the construction will be carried out in consultation with Limerick City & County Council. Pierce McGann & Company, Consulting Civil I Structural Engineers 22 Barrington Street, Limerick. (Rev May 19)
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