The Belfry Resort Risk and Impact Assessment June 2017 Contents

1. Development site and location 2. Development proposal 3. Sequential Test 4. Climate change 5. Site specific flood risk 6. Surface management 7. Occupants and users of the development 8. Exception test 9. Residual risk 10. Flood risk assessment credentials

Revision Issue By Purpose 00 12 June 2017 AC/JS For planning Draft 17 May 2017 AC/JS For comment

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 2 1. Development site and location 1a. Where is the development site located?

The application site described by this Flood Risk Assessment is located at The Belfry Hotel off Lichfield Road, Wishaw, North Warwirkshire, B76 9PR as shown in Figures 1 and 2. The site consists of seven parcels which include: • Parcel A: Bel Air Inn conversion • Parcel B: Ballesteros House conference room • Parcel C: Water Park and Hotel Wing • Parcel D: Derby House conference room • Parcel E: Link Bridge • Parcel F: Parking • Parcel G: Wastewater Treatment Plant

The site covers a total area of approximately 2.06ha, centred on OS grid coordinates 418226E, 295231N. The site is bounded by the M6 Toll road to the south, the A4091 to the east, and the resort’s existing golf course to the west and south. The Local Lead Flood Authority for the development site is Warwickshire County Council (WCC).

1b. What is the use of the site?

The development site is occupied by The Belfry Hotel & Resort. This comprises a 319 bedroom hotel, a leisure club, function rooms and supporting facilities including a selection of restaurants, a Golf Centre, the UK and European headquarters of the PGA as as the PGA Training Academy and Figure 1: Location map the Bel Air night club. The resort includes 986 carparking spaces, located at ground level. To the north of the site are The Belfry’s three golf courses; Brabazon, The Derby and PGA National.

The development site comprises of existing buildings, hard landscaping and carparking space as well as undeveloped land and green landscaping.

1c. Which Flood Zone is the site within?

The Environmental Agency (EA) flood map shows the development site to be within Flood Zone 1 (Figure 3). Areas in Flood Zone 1 are characterised as having a low risk of tidal and fluvial flooding (i.e. 1 in 1000 or greater annual probability) as defined by the National Planning Policy Framework (NPPF). This is consistent with WCC’s Level 1 Strategic Flood Risk Assessment (SFRA).

Bel Air 2. Development proposals Nightclub 2a. What are the developments proposals for this site? Will this involve a change of use of the KEY site and, if so, what will that change be? PGA National Golf Academy It is proposed to redevelop the site by retention and expansion of existing buildings. The development Planning proposal includes: application parcel boundary • Parcel A: Conversion of Bel-Air Nightclub into a spa with hotel rooms. • Parcel B: Proposed conference room and ancillary spaces and associated reconfiguration of Practice Range roadway. • Parcel C: Proposed waterpark within the existing courtyard, extension wing and Figure 2: Planning Application Boundary expanded hotel lobby.

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 3 • Parcel D: Proposed single storey conference room within smaller courtyard space. • Parcel E: Link bridge between bedroom wings. • Parcel F: Conversion of tennis courts into additional parking bays. Net increase of 30 new parking spaces. • Parcel G: Installation of packaged wastewater treatment works to be located below ground.

The proposed development will not change the use of the site.

2b. In terms of vulnerability to flooding, what is the vulnerability classification of the proposed development?

Hotel space is classified as “more vulnerable” and office, shop and leisure space is classified as “less vulnerable” according to Table 2 of the National Planning Policy Framework (NPPF). The overall vulnerability classification of the proposed development is there for “more vulnerable”. According to the NPPF’s Flood Zone Compatibility matrix the development is appropriate.

2c. What is the expected or estimated lifetime of the proposed development likely to be?

Paragraph 26 of NPPF suggests that residential developments should be considered to have a minimum lifetime of 100 years and commercial developments a lifetime of 60 years. This is broadly consistent with the project brief. It is therefore assumed that the development has a lifetime of 50- 100 years. Figure 3: Environment Agency Flood Map

3. Sequential Test 3a. What other locations with a lower risk of flooding have you considered for the proposed development?

Sequential Test is not required as the site lies within Flood Zone 1

3b. If you have not considered any other location, what are the reasons for this?

Sequential Test is not required as the site lies within Flood Zone 1

3c. Explain why you consider the development cannot be reasonably located within an area within flood zone 1; and, if your chosen site is in flood zone 3, explain why you consider the development cannot reasonably be located in flood zone 2.

Sequential Test is not required as the site lies within Flood Zone 1

3d. As well as flood risk from or the sea, have you taken account of the risk from any other sources of flooding in selecting the location for the development?

Sequential Test is not required as the site lies within Flood Zone 1

Figure 4: Ordnance Survey Map 5m contours

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 4 4. Climate change

4a. How is flood risk at the site likely to be affected by climate change?

The development site is located in the proximity of the Tames. The WCC’s SFRA confirms that the flood extents provided by the EA’s Detailed River Network model, includes an allowance for climate change.

Climate change will increase rainfall intensities, which will increase the risk of localised flooding from the existing drainage system.

5. Site specific flood risk

5a. What is/are the main source(s) of flood risk to the site?

Tidal

The development site is located inland and therefore there is no risk of tidal flooding.

Fluvial

The Belfry Hotel and Resort is located at a highpoint within the natural topography of the area as shown on the Ordnance Survey Contour Maps for the area (Figure 4).

The development site falls within Flood Zone 1 which has a low risk of flooding. Moxhull Brook Figure 5: Borehole record locations is located to the east and north of the site and is a notable of the River Tame. Ordnance Survey information shows Moxhull Brook to be located at an elevation between +75-80m OD. Topographical survey information produced by Land Surveys in March 2013 shows that parcels B, C, D and E are located at levels between +84.8-86.9mOD. Parcel A is located at levels between +82.0-84.3m OD. Parcels B,C,D and E are therefore greater than 4.8m above the banks of Moxhull Brook. Parcel A is greater than 2.0m above the banks of Moxhull Brook. As such, there is negligible risk of fluvial flooding to the sites.

Groundwater

Available published map data from the British Geological Survey (BGS) indicates the following strata will be encountered at or near surface within the site boundary:

• Glaciofluvial Deposits (comprising sand and gravel, locally with lenses of silt, clay) • Mercia Mudstone Ground

A desktop geoenvironmental desk study was undertaken by Shepherd Gilmour Environment in June 2006 which includes a review of historical site investigations information. From this report, the ground conditions recorded indicate that the area is underlain generally by a clayey sand layer between 0.5mbgl and 3.40mbgl, over a gravelly clay layer between 2.00mbgl and 8.00mbgl and a brown fine to medium sand layer ranging between 7.00mbgl and 8.45mbgl. This is consistent with historical borehole records, obtained from the BGS. Historical borehole locations are shown in Figure 5.

The groundwater table was not encountered for any of the boreholes reviewed which would indicate that groundwater levels are deeper than 8.45mbgl. As such, there is no risk of groundwater flooding Figure 6: Areas susceptible to groundwater flooding

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 5 to the sites. This is consistent with the WCC’s SFRA Ground water flooding maps which shows that there is a low probability of Groundwater Flooding for the site(Figure 6).

Surface Water Runoff/Sewers

The Belfry Hotel and Resort is located at a highpoint within the natural topography of the area and as a result, surface water drains towards Moxhull Brook or to undeveloped areas to the south of the site. This is consistent with the WCC’s SFRA surface water flood risk map (refer Figure 7), which shows that the site has no risk of flooding from surface water for the 1 in 200 year return storm.

Statutory records obtained through a desktop utility search show that there are no public sewers in the vicinity of the development site.

In conclusion, there is no risk of flooding to the development site from fluvial, groundwater or surface water sources. There is however a residual risk of localised sewer flooding from failure of the onsite drainage systems (ie blockages) or during large storm events where the capacity of the existing system is exceeded. This is discussed further in Section 9.

5b. What is the probability of the site flooding, taking account of the maps of flood risk available from the Environment Agency, the local planning authority’s Strategic Flood Risk Assessment and any further flood risk information?

The probability of flooding on the site is very low as shown on the EA Flood Maps, WCC’s SFRA and other available information. Figure 7: Flood depths for surface water 1 in 200year event 5c. Are you aware of any other sources of flooding that may affect the site?

5g. How will you ensure that the development and any measures to protect the site from We are not aware of any other sources of flooding that may affect the site. flooding will not cause any increase in flood risk off-site elsewhere? Have you taken into account the impacts of climate change, over the expected lifetime of the development? 5d. What is the expected depth and level for the design flood? The development site is not in the fluvial and therefore, will not have any effect on floodplain storage. The design flood level for the development site would be associated with localised flooding from the onsite drainage systems. The expected depth of this design flood is not possible to quantify. This is Runoff from the development site will, where feasible, into new systems. Where discussed further in Section 9. this is not possible runoff will be attenuated in new storage structures and discharged into Moxhull Brook at pre-development runoff rates via the existing outfalls. This approach will mitigate the impact 5e. Are properties expected to flood internally in the design flood and to what depth? of increased runoff to Moxhull Brook caused by the additional impermeable surfaces from the development. No buildings are expected to flood internally. All new infrastructure will be design to NPPF and BS EN 752 which takes into account the effects of climate change. See Section 6 for further details of the surface water drainage strategy. 5f. How will the development be made safe from flooding and the impacts of climate change, for its lifetime? 5h. Are there opportunities offered by the development to reduce the causes and impacts of flooding? The development site is not at risk from fluvial or surface water flooding for events up to the 1 in 100 year return storm including an allowance for climate change. Runoff from the proposed development sites will, where feasible, discharge into new infiltration systems. The surface water drainage strategy will also consider water recycling facilities for buildings The proposed surface water drainage systems will be designed to ensure that all proposed and and discharge of surface water runoff to the balancing lakes for irrigation. This will reduce the overall existing buildings will not be at risk of flooding for events up to 1 in 100 year + 30% for climate change. discharge volume to Moxhull Brook and therefore help alleviate flooding. Additionally, it will reduce potable water demand.

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 6 Ltd, the asset management contractor for the WwTW. A survey of the existing WwTW by Alpheus 6. Surface water management Enviromental Ltd concluded that it is undersized for the existing loads due to limited aeration capacity resulting in very poor final quality during the peak seasons ( and summer). The existing 6a. What are the existing surface water drainage arrangements for the site? plant is nearing the end of its life and is likely to require replacing within the next 5 years.

The Belfry Hotel and Resort has a mostly separate system for foul and surface water runoff. There are There is a licensed outfall for treated foul water to discharge directly to Moxhull Brook and a EA sampling however some small areas of roof and road that drain surface water via the foul system. Foul water pit at National Grid Reference SP1831 9534 to check compliance with the quality requirements of the discharge consent. The current effleunt discharge flow from the WwTW is well within the discharge discharges to an on-site Wastewater Treatment Works (WwTW) and surface water either infiltrates 3 to ground via storm soakaways, discharges to the balancing lakes for irrigation or discharges directly consent of 650 m per day. However, the licensed outfall is reportedly never used. to Moxhull Brook. Refer Figure 8. The treated foul water flows across Moxhull Brook via an above-ground pipe into the high and low There are a number of hydrological features to the east and north of the site which include Moxhull level balancing lakes. The are hydraulically link via a submersed pump and pumping main Brook and , high and low level balancing lakes, an on site reservoir and a series of smaller ponds. in the lower balancing lake and a overflow outlet in the higher balancing lake. From here, water is The Belfry Hotel and Resort hold three licenses with the EA which includes a permit to discharge either used for irrigation of the Brabazon golf course or is pumped to an on site storage reservoir treated from the on-site Wastewater Treatment Works (WwTW) and two water abstraction for irrigation of the PGA or Derby golf course. The reservoir was originally designed with a option licenses. for gravity discharge back to Moxhull Brook via an underground gravity pipe followed by a series of ponds and . However, the gravity pipe is currently broken and cannot be used. Overflow from Moxhull Brook is a relatively small watercourse which flows from south to north along the west the reservoir can be discharged via a high level outfall into a nearby field ditch. boundary of the site. It enters the golf courses via two large twin culverts beneath the M6 Toll Road. Flow and water levels in Moxhull Brook are controlled via a sluice and penstock beside the 6b. If known, what (approximately) are the existing rates and volumes of surface water run-off overflow . The Belfry’s Estate Management staff monitor the forecast and will lower the pond generated by the site? level when rainfall is predicted. Runoff from impermeable areas of the site are drained either by infiltration to ground via storm Licensed abstractions can be made from Moxhull Brook to the balancing lakes when the flow in the soakaways, discharged to the balancing lakes for irrigation or discharged directly to Moxhull Brook. brook exceeds 5.8l/s controlled by a flow control weir and outfall. However, the flow control weir has Green areas are drained to ground. Flows draining to the balancing lakes are reused for irrigation of been constructed at the wrong level and therefore the overflow cannot be used. the golf course and hence do not contribute to the overall discharge rate from the site.

Rainfall runoff discharge routes from impermeable areas of the site have been identified, as far The peak discharge rate to Moxhull Brook will be mostly limited by the capacity of the existing site as practicably possible, through a review of historic utility records, an in-ground drainage survey storm water drainage system. A 1 in 30 year design is generally adopted as the design undertaken by On Centre Surveys issued May 2016 and a site walkover with The Belfry’s Estate event for sizing storm water drainage systems. Therefore, a 1 in 30 year return period has been used Management staff. Each of the development parcels drain in the following ways: to calculate the anticipated peak discharge rate from the impermeable areas draining to Moxhull Brook. • Parcel A: Parking areas are discharged directly to Moxhull Brook via Outfall 1. Green areas naturally infiltrate. Without attenuation storage, the shortest 15 minutes duration storm would generate highest • Parcel B: Roads & parking are discharged to the foul water system. Green areas naturally discharge. Based on the FSR Method used with coefficients M5-60= 19.0mm and R=0.400, the infiltrate. average rainfall intensities for the 15 minute duration storm is 72.01mm/hr for the 1 in 30 year return • Parcel C: Road and roof areas are discharged to the balancing lakes via Stormwater Outfall period. Peak runoff rate has been calculated using the modified rational method as described in 2. Green areas naturally infiltrate. the Wallingford procedure. Based on recommendations from BS EN 752, runoff coefficients of 0.85 • Parcel D: Parking areas are discharged to the balancing lakes via Stormwater Outfall 2. has been adopted for hard landscaping surfaces. The current peak discharge rate from the site to • Parcel E: Road areas are discharged to the balancing lakes via Stormwater Outfall 2. Moxhull Brook is therefore estimated to be 18.6l/s. • Parcel F: Parking areas are discharged to the balancing lakes via Stormwater Outfall 2. Green areas and runoff from tennis courts naturally infiltrate 6c. What are the proposals for managing and discharging surface water from the site, including • Parcel G: Hardstanding areas discharge to the balancing lakes via Stormwater Outfall 2. any measures for restricting discharge rates? Green areas naturally infiltrate The surface water drainage strategy has been developed in line with the following key principles: Foul water is collected from all buildings through a network of pipes and flows into the onsite WwTW. • Hierarchy of disposal routes as set out in WCC’s Draft Flood Risk and Drainage Planning Foul water from the Bel Air Nightclub and PGA National Golf Academy drains to a foul water pumping Advice Version 2. station. From here, flows are pumped to the higher gravity network and then flow by gravity into the • Control peak discharge to mitigate the impact of increased impermeable areas produced by WwTW. the development. • Surface Water drainage design in accordance with the requirements of NPPF and BS EN The WwTW area is occupied by a mix of operating and redundant plant and machinery including a 752 to protect the site from flooding. central pump station, anoxic tanks, aerators, clarifiers, sludge tanks and effluent sampling troughs. • Control of pollution to the water environment in line with the requirements WCC’s Planning Water quality and flow rates of treated effluent is monitored weekly by Alpheus Environmental Advice and the SUDS Manual.

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 7 Figure 8: Existing Drainage System Foul Water Disposal Route The survey of the current treatment plant has revealed insufficient capacity to accomodate the The disposal route for surface water from the site has been developed in line with the WCC’s Planning additional load from an expanded development. It is proposed that a new treatment plant be installed Advice which follows this order: within the footprint of the current WwTW to take flows from the expanded hotel areas. The outflow from this new treatment will also discharge to the balancing lakes for reuse as irrigation and • storing water for later use; hence will not result in an increased discharge rate from the side. Options for the expansion of the • at-source infiltration drainage; WwTW will be explored as part of the design development. • discharge directly to a suitable watercourse; • discharge to a surface water sewer; and Regenerative Media Filter Backwash and Dilution Discharge • discharge to a combined sewer. The new water park will include a regenerative media filter to continuously treat water from the various The application of this hierarchy is discussed below. pools by removing particulate matter and debris from the water. These filters require periodic back washing every 3-4 weeks which is the process of reversing the flow of water through the filter to flush It is recommended that surface water flows, where feasible, are recycled within the building or out the collected debris generating a ‘grey’ water discharge. The peak flow rate from this process discharged to the balancing lakes as part of a strategy to reduce potable water use across the site. is approximately 20 l/s and hence would require hydraulic balancing prior to treatment. Analysis of This will be assessed in the next stage of design. discharges from similar water parks has been provided by Water Technology Inc (WTI), a supplier of water park installations. These show that the discharge is relatively clean but has a medium level Infiltration drainage, where possible, will be used to dispose of surface water subject toground of Total Dissolved Solids and contains some silts and grease. Refer backwash water analysis in investigations. Where this is not possible, surface water will be attenuated in a suitable storage Appendix A. structure with a flow control device before discharge to Moxhull Brook. Discharge rates willbe limited to pre-development rates to mitigate the impacts from increased impermeable area from the Additionally the new water park will require a constant trickle of freshwater to reduce the buildup of development. pollutants from bathers and the by-products of disinfection. This process generates an additional ‘grey’ water discharge released as a constant trickle at a flow rate of approximately 0.4l/s. This discharge Design Event will have a similar level of Total Dissolved Solids as the backwash flow, but will have slightly higher chlorine levels and lower silt and grease levels. The surface water drainage system will be design for: Given the volume and quality of discharges from the water park, it would not be sustainable to discharge • No surface water flooding for all events up to 1 in 30 year return period, in line with BS EN 752. to the foul water treatment system. It is proposed that options for reuse of a proportion of backwash • No flooding of the buildings for extreme events up to the 1 in 100 year return period are explored for flushing of toilets within the water parks changing rooms. Remaining flows will including a 30% allowance for climate change, in line with NPPF. be balanced and treated prior to discharge into the Belfry’s lake network and utilised for irrigation, with • Containment on site of any flooding associated with the 1 in 100 year + 30% event any overflow discharged to the Moxhull Brook.

Peak discharge rate Backwash flows will contain silt and grease and therefore treatment options should include sedimentation and filtration of flows through a or reed bed. If required, a grease Runoff from the site will be discharged via at-source infiltration or direct discharge to Moxhull Brook trap could be included before the constructed wetland/reed beds as an additional treatment step at the calculated pre-development runoff rate. A minimum discharge rate of 5l/s per outfall will be to remove excess grease. Dilution water discharge may have higher chlorine levels and therefore applied to avoid potential risk of blockages. treatment options should include aeration through bubblers in the pond or cascading water. Both flows should discharge to the balancing lakes for dilution of Total Dissolved Solids before discharge Pollution Control to Moxhull Brook.

In line with the SUDS manual there is a medium risk of pollution of the water environment associated Discharge options for the backwash flows will be agreed in consultation with the EA. with the development. Runoff from the additional parking spaces will undergo a two-stage treatment process and where possible infiltrated to ground in line with WCC’s Draft Flood Risk and Drainage 6d. How will you prevent run-off from the completed development causing an impact elsewhere? Planning Advice Version 2. Runoff from roofs are considered to have a low pollution level and hence will be infiltrated directly to ground or undergo a one-stage treatment process before discharge to Moxhull Brook. Treatment stages could include: swales, filter strips, reed bed, infiltration system or a Runoff from the site will be discharged via at-source infiltration or direct discharge to Moxhull Brook proprietary treatment system. at the calculated pre-development runoff rate. Therefore the impact of the development on Moxhull Brook is minimal.

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 9 6e. Where applicable, what are the plans for the ongoing operation and/or maintenance of the 8b. How can it be demonstrated that the proposed development will remain safe over its surface water drainage system? lifetime without increasing flood risk elsewhere?

The operation and maintenance of the drainage system is the responsibility of the property owners. Exception test not required as development is appropriate. The following routine inspections and maintenance are required: • 3-monthly inspections of drainage and infiltration systems for signs of blockage. 8c. Will it be possible to for the development to reduce flood risk overall (eg. through the • Remove litter and blockages as required. provision of improved drainage)? • Every 12 months inspect all chambers for silt build up. • Every 12 months sweep external surfaces. • Remove silt (and oil) as required but at least every year. Exception test not required as development is appropriate.

The proposed storage structure will require regular inspection to remove silt and debris as required. The hydrocarbon interceptor will require regular inspections to remove the hydrocarbons. 9. Residual risk

9a. What flood related risks will remain after the flood risk management and mitigation 7. Occupants and users of the development measures have been implemented?

7a. Will the development proposals increase the overall number of occupants and/or people using the building or land, compared with the current use? There is a residual risk of localised flooding at low points of the site from failure of the existing onsite drainage systems (ie blockages) or during large storm events where the capacity of the existing system is exceeded. Any new development will need to ensure that where additional flows are The proposed development will increase the overall number of short term occupants, due to the proposed to drain to the existing system that this does not increase flood risk to any other areas of additional bedrooms. The number of day visitors will also increase due to the additional leisure the site. This should include an assessment of the existing capacity of the system and the potential space, new water park and conference space. impact of increased flows.

7b. Will the proposals change the nature or times of occupation or use, such that it may affect Buildings will be protected from localised flooding by ensuring, where possible, that site levels drain the degree of flood risk to these people? away from buildings and all buildings have raised threshold and finished floor levels.

The proposed development will not change the nature and or time of occupation and hence the 9b. How, and by whom, will these risks be managed over the lifetime of the development? degree of flood risk to people. Provision will be made in the building management plan to ensure that the drainage system is 7c. Where appropriate, are you able to demonstrate how the occupants and users that may be regularly maintained as discussed in Section 6e. more vulnerable to the impact of flooding (eg. residents who sleep in the building, people with health or mobility issues) will be located primarily in the parts of the building and site that are at the lowest risk of flooding? 10. Flood risk assessment credentials

The development is at low risk of flooding for the 1 in 100 year event including an allowance for 10a. Who has undertaken the flood risk assessment? climate change. Hence this approach does not need to be applied. Expedition director Judith Sykes (FICE MEng CEng) and Expedition Civil Engineer Anna Collins, (BEng (Hons)) have carried out this flood risk assessment. They both have extensive water-related 8. Exception test engineering experience in the UK and internationally.

8a. Would the proposed development provide wider sustainability benefits to the community? 10b. When was the flood risk assessment completed? If so, could these benefits be considered to outweigh the flood risk to and from the proposed development? This flood risk assessment was completed on 12 June 2017.

Exception test not required as development is appropriate.

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 10 APPENDIX A - BACKWASH WATER ANALYSIS

The Belfry Hotel and Resort Flood Risk and Drainage Impact Assessment - June 2017 11