Three Rivers and Watford LDF

Executive Summary Report

January 2012

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall 28-32 Upper Ground Pegs Lane London SE1 9PD Hertford SG13 8DN +44 (0)20 7910 5000 www.steerdaviesgleave.com

Executive Summary

CONTENTS

1 THREE RIVERS AND WATFORD LDF MODELLING ...... 1 Background and Study Objectives ...... 1 Base 2010 Model ...... 1 Future Year Model Development ...... 3 2026 LDF Sites ...... 10

TABLES

Table 1.1 Summary of Committed Development – Three Rivers ...... 3 Table 1.2 Summary of Committed Development - Watford ...... 4 Table 1.3 Summary of Potential Development – Three Rivers ...... 7 Table 1.4 Summary of Potential Development - Watford ...... 8 Table 1.5 Future Year Matrix Totals ...... 9 Table 1.6 Potential Future Year Mitigation Summary ...... 12

Contents

Executive Summary

1 Three Rivers and Watford LDF Modelling

Background and Study Objectives

1.1 The central part of the existing South West Herts SATURN Highway Model, taking in the town centre and the area west of the town towards Rickmansworth, has recently been updated to represent 2010 base year conditions to support the assessment and appraisal of the successful bid for Croxley Rail Link funding.

1.2 Three Rivers District Council and Watford Borough Council both agreed with Hertfordshire County Council to make use of the SATURN model to provide evidence to support the associated consultation on LDF documents.

1.3 A future year of 2026 has been taken to correspond with the Three Rivers LDF timetable. Given that the difference in flows to 2031 would be slight, the modelling results remain relevant to Watford who are working towards 2031.

1.4 Clearly, the LDF sites are not constrained to the central part of the highway model defined above and, as such, there was a need to incorporate this update into the wider SATURN model to allow the potential transport impacts of the combined strategies to be evaluated. The wider SATURN model includes much of the administrative area of Three Rivers District Council, all of the area of Watford Council and a small part of Hertsmere District Council (Bushey and Bushey Heath)

1.5 The report provides a stand-alone Executive Summary of the modelling work undertaken to update and utilise the highway model to assess the implications of future growth in development across Three Rivers and Watford to 2026. More detail on individual modelling tasks are included in three separate technical reports;

I Technical Note 1: Base 2010 Model I Technical Note 2: Future Year Model Development I Technical Note 3: 2026 LDF Sites 1.6 The remainder of this report provides a summary of the tasks undertaken and the conclusions derived at each stage of the study.

Base 2010 Model

1.7 As explained above, there was a need to incorporate the update of the highway model carried out to support the Croxley Rail Link (CRL) appraisal into the wider SATURN model to provide evidence of the potential transport impacts of the combined strategies of Three Rivers District Council and Watford Borough Council in support of their LDF site allocation consultation.

1.8 Any changes to modelled traffic flow to and from the updated central area have been reflected in the wider model, along with relatively minor changes to the representation of the highway in this central area to reflect in more detail the routes deemed likely to be affected by the CRL scheme.

1.9 Following this, the main update task related to the comparison of traffic flow forecasts within the updated model with latest count data. It was agreed that any

1 Executive Summary

update of the model would make best use of available data and a request for new automatic count data was made with Herts Highway’s data collection team. Data was received for a total of 18 sites across the wider model area.

1.10 Data was made available for a consistent week in each year between 2007 and 2011. Across all sites, no consistent pattern of growth through the five years available was identified and, as such, flows for 2010 have been used for flow calibration. This is consistent with data used for the update of the central area.

1.11 Initial model calibration against 2010 flows was poor, and identified a need to carry out additional flow calibration of the wider model area.

1.12 Where appropriate, calibration of modelled flows to link counts was dealt with manually, particularly to better reflect observed flows on the edge of the model area. However, this did not improve calibration sufficiently across the whole modelled area and it was also necessary to carry out a process known as matrix estimation in an attempt to improve the match against the 18 new count locations, in each direction.

1.13 The resulting matrices were re-assigned to the wider model network and resulting modelled flows again compared against the count locations. Flow comparisons are evaluated both in terms of absolute and percentage differences and a specific modelling comparator, the geh-statistic.

1.14 Overall, model flows compare well to observed count data in models of both the morning and evening peak hours. Reasonably accurate flow calibration is achieved for some 81% of comparisons in the AM peak and 83% in the PM peak.

1.15 There are, however, selected areas where calibration is not so good. It tends to underestimate AM peak flow in the base year on the A41 North Western Avenue in Garston and southbound on A411 Hempstead Road, immediately south of the Hunton Bridge gyratory. In the PM peak, again flow on the northern section of Hempstead Road is underestimated, as is flow on the High Road in Leavesden.

1.16 These discrepancies need to be kept in mind when interpreting model results in future years.

Conclusions 1.17 Having incorporated updates to the central area to the wider model area, the initial comparison of assigned flows to counts did not result in many matches and the need for a relatively minor update to the calibration was identified.

1.18 It should be noted that this model update exercise represents a calibration of model flow against already available count data only, and should not be regarded as a model upgrade, particularly given that no additional information has been gathered on origins and destinations of journeys within the model area.

1.19 However, it is believed that the resulting 2010 base model provides a suitable base point for the preparation of a transport evidence base to support the LDF consultation process.

2 Executive Summary

Future Year Model Development

1.20 Following agreement of the 2010 Base Model, we then evaluated the level of traffic forecast to be generated by sites identified as committed developments in each of the Three Rivers and Watford areas and sought to identify any network improvements, some of which are also committed, that are likely to be required to support this committed growth. Except where committed infrastructure proposals are identified, such improvements to the network are constrained to relatively modest upgrades, which we believe can be delivered within existing highway boundaries.

1.21 A future year of 2026 has been taken to correspond with the Three Rivers LDF timetable. Given that the difference in flows to 2031 would be slight, the modelling results remain relevant to Watford who are working towards 2031.

Committed Developments 1.22 The table below lists the committed developments identified within the Three Rivers district and provides the development size, type and generated trip forecasts. Where available, trip forecasts have been taken directly from the individual development Transport Assessments (TAs). Where such information isn’t available, residential trip rates are derived from those TAs that are available for similar developments, with rates extracted from the TRICS database for other land uses. The following generic rates are applied.

I Housing (per dwg): AM In=0.170, AM Out=0.410, PM In=0.380, PM out=0.230 I B2/B2 (per 100m2): AM In=0.456, AM Out=0.094, PM In=0.044, PM out=0.339 I Office (per 100m2): AM In=1.483, AM Out=0.172, PM In=0.139, PM out=1.235 I Retail (per 100m2): AM In=9.311, AM Out=6.580, PM In=7.883, PM out=11.173 I Hotel (per bed): AM In=0.091, AM Out=0.113, PM In=0.097, PM out=0.084

TABLE 1.1 SUMMARY OF COMMITTED DEVELOPMENT – THREE RIVERS

Dev. Size Development Type Generated Trips

AM in AM Out PM In PM Out

Abbots Langley

33 units Residential 6 13 12 7

Carpenders Park

33 units Residential (inc Rear of 5 14 13 7 Kebbel House)

Chorleywood

54 units Residential 9 22 20 12

3 Executive Summary

Croxley Green

204 units Residential (inc Old 35 83 76 47 Merchant Taylors and Durrants)

Moor Park and Eastbury

37 units Residential 6 15 14 8

Kings Langley

4 units Residential 1 2 2 1

Rickmansworth

110 units Residential (inc 3a High St) 15 38 35 20

South Oxhey

31 units Residential 5 13 12 7

Leavesden

425 units Residential 72 173 160 96

Studio Studio Tours 33 2 137 168

Total Generated Trips 187 375 481 373

1.23 For Three Rivers, the predicted total of newly generated trips amounts to an additional 562 two-way trips in AM modelled period and 854 in the PM modelled period.

1.24 Similarly, the table below identifies the number of trips generated from the committed developments within the different wards around Watford.

1.25 For Watford, the total generated trips amount to an additional 2573 two-way trips in AM modelled period and 2329 in the PM modelled period.

TABLE 1.2 SUMMARY OF COMMITTED DEVELOPMENT - WATFORD

Dev. Size Development Type Generated Trips

AM in AM Out PM In PM Out

Leggatts Ward

225 units Residential (inc Leggatts 30 76 69 29 Campus)

Vicarage Ward

74,000 Health Campus -Hospital 923 216 183 553 sqm

4 Executive Summary

5,005 Health Campus -Restaurant 0 0 106 83 sqm

14,715 Health Campus - Hotel 53 65 64 37 sqm

18,780 Health Campus -Offices 281 34 28 234 sqm

504 units Health Campus -Residential 41 117 107 54

48 units Other Residential 8 20 18 11

Woodside Ward

73 units Residential 9 20 19 11

Callowland Ward

65 units Residential 11 26 25 15

Central Ward

420 units Residential 64 158 145 89

Holywell Ward

119 units Residential 20 48 44 26

Meriden Ward

167 units Residential 25 65 66 43

Nascot Ward

332 units Residential 53 122 108 72

Oxhey Ward

136 units Residential 14 33 31 19

Park Ward

25 units Residential 4 10 10 6

Stanborough Ward

34 units Residential 6 14 13 8

Tudor Ward

9 units Residential 2 4 3 2

Total Generated Trips 1544 1028 1035 1294

5 Executive Summary

1.26 These new trips are added to the base matrices for the AM and PM peaks to provide a ‘Base + Committed’ scenario.

1.27 Before assigning the 2026 matrices to the model, the following network improvements are assumed:

I Health Campus Link . Connecting Dalton Way to the Health Campus site via Wiggenhall Road . Left-in/left-out junction provided at Dalton Way (one-way operation) . New signalised junction with Wiggenhall Road: Layout shown in Appendix B I Colonial Way Extension . Connecting Colonial Way from its junction with Imperial Way to St Albans Rd . All moves signalised junction with St Albans Lane . New rear entrance to Watford Junction Station car parks, forming a new signalised junction with Colonial Way Extension

1.28 Initial assignment of the ‘Base+Committed’ matrices identified a number of areas where stress on the network, in terms of queues and delays, are increased significantly over the 2010 base scenario. An assessment of each location has been carried out to make a judgement as to whether increased capacity could realistically be delivered to accommodate additional levels of traffic associated with the committed development. It seems reasonable to assume that developers of those committed schemes will be expected to contribute in some way to network improvements.

1.29 In some cases, improvements are delivered through optimisation of traffic signals. However, where increased physical capacity is required, solutions are constrained through a broad assessment of land availability, although it must be stressed that a more detailed assessment would be required if any of the schemes proposed were to be progressed. A summary of additional changes made to the network to accommodate committed development is provided below.

I Coding of additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre I Provision of additional right turn lanes into and out of Glen Way and Grove Mill Lane at their junctions with A411 Hempstead Road

Potential Development 1.30 Sites identified for potential development, beyond those already committed, have similarly been identified for both Three Rivers and Watford. The following tables provide a summary of developments and the forecast numbers of generated trips. In Three Rivers future housing allocations are identified across seven wards. For Watford, potential development is focussed mainly at Watford Junction, the town centre and at Watford Business Park.

6 Executive Summary

TABLE 1.3 SUMMARY OF POTENTIAL DEVELOPMENT – THREE RIVERS

Dev. Size Development Type Generated Trips

AM in AM Out PM In PM Out

Abbots Langley

75 units Residential 13 30 31 17

Croxley Green

145 units Residential (inc 25 58 55 33 Killingdown Farm, Former Croxley Green Station & South Tolpits Lane)

Langleybury

310 units Residential (inc Kings 53 125 116 70 Langley & Langleybury House)

Leavesden

80 units Residential (inc Brickett 14 32 30 18 Wood & Hill Farm Industrial Estate)

Rickmansworth

263 units Residential (inc Long Island 45 107 99 59 Exchange & Stockers Farm Road)

16,000 B2/B8 Employment – Maple 73 15 7 63 sqm Cross

Sarratt

10 units Residential 2 4 4 2

South Oxhey

473 units Residential (inc Little 81 192 178 107 Furze School, Land South of St Josephs, South Oxhey Town Centre Regeneration & Heysham Drive)

Total Generated Trips 304 566 516 370

7 Executive Summary

TABLE 1.4 SUMMARY OF POTENTIAL DEVELOPMENT - WATFORD

Dev. Size Development Type Generated Trips

AM in AM Out PM In PM Out

Central

1,200 Watford Junction Station - 204 487 451 272 units Residential

23,225 Watford Junction Station – 344 40 32 287 sqm Offices

300 bed Watford Junction Station - 27 34 29 25 Hotel

56,458 Town Centre (net increase) 71 11 277 393 sqm

96 units Metropolitan Station 16 39 36 22 Approach - Residential

Holywell

3,716 Western Gateway – net 346 245 293 415 sqm increase in retail

Total Generated Trips 1010 856 1117 1413

Traffic Growth and Matrix Sizes 1.31 Target traffic levels in 2026 are derived from the application of background growth rates to the 2010 base traffic flows. Following the addition of committed and potential development, background growth is adjusted to account for the ‘gap’ between identified development and the 2026 target levels.

1.32 The Tempro (v6.2) database has been interrogated to identify the expected growth in car driver trips between the years of 2010 and 2026. The average of origin and destination growth is used. Furthermore, there are differences in predicted growth between Watford and Three Rivers and, as such, growth rates for Hertfordshire is applied which is slightly below growth for Watford and a little above growth for Three Rivers. Given the coverage of model area, this seems reasonable. The growth rates applied are:

I AM Peak: 2010 to 2026 1.142 I PM Peak: 2010 to 2026 1.144 1.33 These growth rates define an upper limit of future year trips by 2026, most of which is accounted for by a combination of trips associated with committed (COM) and potential (POT) development sites. The following year provides a breakdown of future year matrix totals.

8 Executive Summary

TABLE 1.5 FUTURE YEAR MATRIX TOTALS

Matrix Scenario Breakdown Total 2026 2010 COM POT Growth

AM Peak:

Base + COM only 50925 3104 - - 54029

Base + COM + residual growth 50925 3104 - 4125 58154

Base + COM + POT + res. growth 50925 3104 2742 1375 58146

PM Peak:

Base + COM only 54829 3150 - - 57979

Base + COM + residual growth 54829 3150 - 4771 62749

Base + COM + POT + res. growth 54829 3150 3428 1316 62723

Conclusions 1.34 Committed development sites in both the Three Rivers district and in Watford have been identified and associated forecasts of trip generation indicate that we expect to be adding some 3,104 extra 2-way trips to the model network in the AM peak, and a similar increase of 3,150 in the PM peak.

1.35 Committed development includes the Health Campus proposals and, as such, the network includes the new Health Campus link road from Dalton Way via a new signalised junction with Wiggenhall Road. In addition, it is assumed that Colonial Way Extension will be delivered by 2026.

1.36 Assigning demand associated with committed development to the updated network identified other locations where it appears feasible that capacity improvements could be implemented to help accommodate additional demand associated with committed development. These include optimisation of traffic signals at a number of junctions, physical changes to the network at junctions along Hempstead Road and additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre.

1.37 Overall, whilst there are few problems on the network with the network improvements identified, it is predicted that operation of the junction of Eastbury Road/Deacons Hill is likely to be cause for concern in future years, with increased delay also predicted on the approach to Rickmansworth in the morning peak and along Hempstead Road in the evening peak.

9 Executive Summary

2026 LDF Sites

1.38 Once future year trip matrices have been established, and the level of future year networks changes required to help accommodate committed development has been identified, we then assess the additional impact of potential LDF sites.

1.39 The assessment specifically considered growth up to 2026, constrained by Tempro, under two scenarios.

I Base + Committed Development + Residual Growth to 2026 I Base + Committed and Potential Developments + Residual Growth to 2026 (LDF Scenario)

1.40 First a comparison was made of the ‘Base+Committed+Growth’ assignment against the ‘Base+Committed’ only results, to help illustrate those areas affected by additional demand growth beyond those sites where committed development has been identified. Second, we compared differences in 2026 model performance when a proportion of the future growth is allocated to directly to sites which have been identified as potential sites for further development through both Three Rivers’ and Watford’s ongoing LDF process.

1.41 For each scenario, we identified those sections of the network expected to operate above capacity by 2026 and how the patterns differs from the ‘Base + Committed’ only.

1.42 With ‘Base+Committed+Growth’, there is little control over where the growth occurs. The majority of routes show an increase in flow with the additional demand and the majority of the increase is shown on the motorways which, given growth is relatively unconstrained and that the strategic network is most heavily trafficked, is not a surprise.

1.43 Perhaps more interestingly, the changes in delay on the network are relatively low and suggest that the model adjusted to best accommodate committed development demand, can also largely accommodate further growth to 2026.

1.44 With future growth focussed on those areas identified in the LDF as having potential to deliver additional development (LDF Scenario), we see changes in the distribution of traffic across the network. In both peaks there is a reduction in flow on the M25 and M1 links implying that the growth is more self-contained within the study area when applied to potential allocations. We see increased demand for busy routes between Rickmansworth and Watford, but in the PM peak, where we have more trips associated with the potential sites, the impact is greater and also shown to extend beyond Rickmansworth along the A412 Uxbridge Road to the M25.

1.45 Comparing the LDF scenario against ‘base+committed’ only, we see pressures, in the AM peak, focussed on Watford, with network stress in West Watford and around the Bushey Arches gyratory. In the PM peak we predict changes in stress patterns around south-west Rickmansworth and increased stress at Watford Business Park and outbound on St Albans Road.

1.46 When trips associated with potential LDF sites are assessed independently, we can link increases in demand to some of the problem areas identified, seeing significant increases forecast for Ascot Road, Hempstead Road ( as far as Langley

10 Executive Summary

Road) and through the St Albans Road/Station Road junction in the AM peak. In the PM peak we also forecast greater increases along Hempstead Road, which are likely to be a cause of the problems at Courtlands Drive and Hunton Bridge.

1.47 The other problem areas of Eastbury Road/Deacons Hill, Bushey Arches and the western side of Rickmansworth are all areas of existing congestions, expected to worsen with growth to 2026.

Impact on the Strategic Road Network 1.48 Unconstrained growth to 2026 is predicted to add between 7-17% traffic to the motorway junctions within the study area, with M1 Junction 6 seeing the greatest increase. With growth constrained to LDF sites, we generally see a 2-3% reduction in the AM peak, and up to 4% in the PM peak.

1.49 However, it should be noted that while the motorway network is included in the highway model, these routes are not modelled in the same level of detail as the more central parts of the model area and queues and delay are not validated. We therefore have less confidence in the flows quoted for these outer ‘buffer’ parts of the model and recommend that it is the absolute changes in flow that should be considered, rather than the actual flows quoted.

Implications for Public Transport 1.50 Development related trips are generally spread across the network, and main radial routes into and out of the town, particularly from the north and west, are well served by existing bus services, linking Watford and Rickmansworth to surrounding towns. Also, the Croxley Rail Link proposals introduce new rail stations at both Ascot Road and at the Health Campus, which will provide additional public transport options to each of these key employment destinations.

1.51 Similarly, it can be implied that these model results represent a worst case given that no account is made of expected reductions in flow on local highways as a result of the Croxley Rail Link (CRL) scheme nor Abbey Line improvements. It is worth noting that for CRL alone, the supporting Transport Assessment indicates a predicted reduction of some 287 peak hour trips from the network following introduction of the scheme as drivers change mode from the car to rail. These reductions in flow offer moderate improvement in future year operational conditions at both the Rickmansworth Road/Ascot Road and Ascot Road/Whippendell Road junctions.

Future Mitigation 1.52 Growth in traffic on the network to 2026 will both add to pressures at locations where congestion is already a cause for concern, and introduce new concerns. The following table brings together the various proposals put forward, both to accommodate traffic associated with committed development proposals and beyond. For each solution, a scale of costs is also provided, although this must at this stage be taken as an indication only. Further detailed design and consideration of land costs would be needed to validate these costs.

11 Executive Summary

TABLE 1.6 POTENTIAL FUTURE YEAR MITIGATION SUMMARY

Definition Description Funding / Cost

Major Schemes

Health Campus Link New link from development to Dalton Way Developer led via Wiggenhall Road

Colonial Way Link Extension of Colonial Way to St Albans Rd Developer led

Croxley Rail Link New rail link from Croxley to Watford Funding has been Junction Station, inc new stations at Ascot agreed by Rd and Health Campus Government

Committed Developments

Signal optimisation Clarendon Road/ St Johns Road Low cost Hempstead Road/ Langley Way Exchange Road/ Market Street

Capacity improvement Increased circulatory capacity A412/A404 <£1m roundabout

RT lanes into/out of Glen Way and Grove <£0.25 Mill La at junctions with Hempstead Road

Additional Mitigation

Bus re-routing Re-route W30 service along Low cost Rickmansworth Rd rather than via Watford Met Station

New bus services New service between Watford Business <£1m (subsidy?) Park and Rickmansworth

Signal optimisation St Albans Road/ Sheepcot Lane Low cost

Capacity improvement M25 spur approach to Hunton Bridge rbt – ~£1m widening approach/circulation or signalisation

Eastbury Road/ Deacons Hill – possible LT <£1m up to £5m+ lane from Deacons Hill or major land-take

St Albans Rd/ Station Rd – possible 2-lanes <£1m northbound out of junction & review of parking

Bushey Arches – major scheme? £10m+

12

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Executive Summary

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 22404201

ISSUE HISTORY

Issue No. Date Details

1 January 2012 Draft 2 1 February 2012 Final

REVIEW

Originator Steve Oliver

Other Contributors

Review by: Print Steve Oliver

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

L:\Projects\224\0\42\01\Outputs\Working Notes\LDF Modelling - Executive Summary Report2b.docx

Control Sheet Three Rivers and Watford LDF

Technical Note 1: 2010 Base Model Technical note

August 2011

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall West Riding House Pegs Lane 67 Albion Street Hertford Leeds LS1 5AA SG13 8DN +44 (0)113 389 6400 www.steerdaviesgleave.com

Technical Note 1: 2010 Base Model

CONTENTS

1 TASK 1: BASE 2010 MODEL ...... 1 Introduction ...... 1 Network ...... 1 Matrix ...... 1 Additional Data ...... 2 Update Calibration ...... 3 Conclusion ...... 6

TABLES

Table 1.1 Calibration Counts ...... 2 Table 1.2 Trip Matrix Totals ...... 4 Table 1.3 Flow Calibration – AM Peak ...... 5 Table 1.4 Flow Calibration – PM Peak ...... 6

Contents

Technical Note 1: 2010 Base Model

1 Task 1: Base 2010 Model

Introduction

1.1 The central part of the South West Herts SATURN Highway Model, taking in the town centre and the area west of the town towards Rickmansworth, has recently been updated to represent 2010 base year conditions to support the assessment of the Croxley Rail Link.

1.2 There is now a need to incorporate this update into the wider SATURN model to provide evidence of the potential transport impacts of the combined strategies of Three Rivers District Council and Watford Borough Council in support of their LDF site allocation consultation.

Network

1.3 Records of changes to the network in the central have been maintained, and the same changes have been made to the wider model.

1.4 The most significant changes to the structure of the network are summarised below:

I Harwoods Road made one-way between Vicarage Road and Whippendell Road. I Connection from Euston Rd to the junction of Whippendell Road/Queens Avenue has been stopped up. I Traffic signal control added to the junction of Rickmansworth Road/Metropolitan Station Approach.

1.5 In addition, a revision of zone connections has also been undertaken, particularly in the Croxley Green area (zones 331 and 332) and for zones connecting directly to Rickmansworth Road and/or Tolpits Lane. Two zones (322 and 333) previously connected between Rickmansworth Road and Tolpits Lane, despite no physical connections between the two routes. These have now been separated such that development to the south of Rickmansworth Lane is now catered for by zone 333 and development to the north of Tolpits Lane by zone 322.

Matrix

1.6 In updating the central area, a cordon matrix has been developed. When the cordon was initially created from the wider SATURN model, records were stored of the origins of all trips entering the central area along each cordon link. Similarly the destinations of all trips leaving the central area were also stored.

1.7 To ‘feed back’ the update cordon matrix into the wider model demand matrices, the following steps have been undertaken:

I Zones internal to the central cordon area are identified, and trips between these nodes are removed from the wider model matrix. I These are replaced with updated trips internal to the cordon (Internal- Internal).

1 Technical Note 1: 2010 Base Model

I For trips into the cordon area (External-Internal), the number of trips entering along a particular link is then factored in proportion to the origins stored for that link. I Similarly, for trips out of the cordon area (Internal-External) the number of trips leaving along a particular link are assigned in proportion to the stored destinations. I To create a set of trips passing through the cordon (External-External), a combination of origins from the entry link and destinations from the exit link are used. I It is then acknowledged that it is possible for alternative routes to be used between any two external zones and, as such, the External-External matrix derived in the step above is subtracted from the wider area matrix, leaving those external trips that do not pass through the central area. I Each step is then added together to create the updated wider area matrix. 1.8 This exercise is repeated for each of the AM and PM peaks and results in the following matrix totals, suggesting that the evening peak is busiest in the wider model area.

I AM Peak: 53391 trips I PM Peak: 56334 trips

Additional Data

1.9 Once the network and matrices had been updated, the next stage was to compare the updated model with latest count data. A request for new automatic count data was made with Herts Highway’s data collection team and data was received for a total of 18 site, in each direction.

1.10 Data has been made available for a consistent week in each year between 2007 and 2011. Across all sites, there is no consistent pattern of growth through the five years available. Similarly there is no real suggestion at any of the sites that the 2010 flows would not be expected. As such, flows for 2010 have been used for flow calibration and is consistent with data used for the update of the central area.

1.11 The sites used for flow calibration are listed in the table below.

TABLE 1.1 CALIBRATION COUNTS

Reference Location AM Peak PM Peak

153 Colne Way, Watford S: 1425 S: 1118 E: 1215 E: 1260

154 North Western Avenue, Garston E: 1213 E: 1099 W: 1042 W: 1207

155 Watford Road, Leavesden N: 831 N: 866 S: 958 S: 1066

156 Watford Road, Langleybury N: 637 N: 699

2 Technical Note 1: 2010 Base Model

S: 637 S: 832

206 Rickmansworth Road, Chorleywood W: 835 W: 904 E: 973 E: 895

207 London Road, Batchworth Heath E: 892 E: 1040 W: 1008 W: 794

208 Hempstead Road, Watford N: 809 N: 1096 S: 1123 S: 910

214 St Albans Road, Garston N: 525 N: 716 S: 815 S: 740

215 St Albans Road, Watford N: 553 N: 488 S: 426 S: 449

216 Scots Hill, Rickmansworth W: 1087 W: 1087 E: 1018 E: 1167

252 Oxhey Lane, Watford N: 573 N: 685 S: 751 S: 782

317 Sandy Lane, Eastbury N: 585 N: 567 S: 627 S: 669

346 Moor Lane, Batchworth W: 582 W: 715 E: 731 E: 403

351 Prestwick Road, South Oxhey S: 363 S: 569 N: 650 N: 476

453 Horseshoe Lane, Leavesden W: 349 W: 414 E: 394 E: 374

454 High Road, Leavesden S: 460 S: 213 N: 170 N: 298

542 Rickmansworth S: 986 S: 685 N: 705 N: 1082

562 Uxbridge Road, Rickmansworth E: 676 E: 978 W: 923 W: 731

Update Calibration

1.12 Initial calibration against 2010 flows was poor, and identified a need to carry out additional model flow calibration of the wider model area, beyond the cordon.

1.13 Where possible, calibration of modelled flows to link counts has been dealt with manually, and minor changes to a small number of external zone feeds have been made to better reflect observed flows on the edge of the model area. However, it

3 Technical Note 1: 2010 Base Model

has also been necessary to carry out matrix estimation (SATPIJA/SATME2) in an attempt to improve the match against the 36 directional counts detailed above.

1.14 The following table provides a comparison of trip matrix totals before and after the recalibration to a 2010 base for each of the AM and PM peaks. As shown, overall demand in the PM peak remains relatively stable, yet the AM peak is reduced further by around 3.5%.

TABLE 1.2 TRIP MATRIX TOTALS

AM Peak PM Peak

Pre-calibration 53391 56334

Post-calibration 51511 56489

% difference -3.5% +0.3%

1.15 The resulting matrices are re-assigned to the wider model network and resulting modelled flows compared against the 36 counts available.

1.16 The following tables provide resulting flow comparisons, in terms of absolute and percentage differences and the modeller’s geh-statistic, where a value less that 5 is considered a good fit between any two flows.

4 Technical Note 1: 2010 Base Model

TABLE 1.3 FLOW CALIBRATION – AM PEAK

Site Ref Location Anode Bnode Observed Model Diff %diff geh 153 Colne Way, Watford 5057 5038 1425 1227 -198 -14% 5.44 5038 5058 1215 969 -246 -20% 7.44 154 North Western Avenue, 5004 5011 1213 703 -510 -42% 16.48 Garston 5009 5004 1042 883 -159 -15% 5.13 155 Watford Road, Leavesden 5050 1020 831 828 -3 0% 0.10 1020 5050 958 1074 116 12% 3.64 156 Watford Road, Langleybury 1020 9017 637 594 -43 -7% 1.73 9017 1020 637 632 -5 -1% 0.20 206 Rickmansworth Road, 1009 9008 835 953 118 14% 3.95 Chorleywood 9008 1009 973 976 3 0% 0.10 207 London Road, Batchworth 3044 9006 892 1047 155 17% 4.98 Heath 9006 3044 1008 1103 95 9% 2.92 208 Hempstead Road, Watford 5020 5086 809 703 -106 -13% 3.86 5086 5020 1123 724 -399 -36% 13.13 214 St Albans Road, Garston 5055 5017 525 626 101 19% 4.21 5017 5056 815 1176 361 44% 11.44 215 St Albans Road, Watford 95022 5043 553 434 -119 -22% 5.36 5043 95022 426 682 256 60% 10.88 216 Scots Hill, Rickmansworth 3014 3008 1087 1240 153 14% 4.49 3008 3014 1018 1028 10 1% 0.31 252 Oxhey Lane, Watford 4015 4037 573 538 -35 -6% 1.48 4037 4015 751 684 -67 -9% 2.50 317 Sandy Lane, Eastbury 4022 4032 585 693 108 18% 4.27 4032 4022 627 483 -144 -23% 6.11 346 Moor Lane, Batchworth 3017 3010 582 682 100 17% 3.98 3010 3017 731 775 44 6% 1.60 351 Prestwick Road, South 94034 4034 363 387 24 7% 1.24 Oxhey 4034 94034 650 600 -50 -8% 2.00 453 Horseshoe Lane, Leavesden 5066 5065 349 296 -53 -15% 2.95 5065 5066 394 288 -106 -27% 5.74 454 High Road, Leavesden 5062 5040 460 460 0 0% 0.00 5040 5062 170 156 -14 -8% 1.10 542 Rickmansworth 1011 3009 986 1027 41 4% 1.29 3009 1011 705 979 274 39% 9.44 562 Uxbridge Road, 3013 3003 676 669 -7 -1% 0.27 Rickmansworth 3003 3013 923 992 69 7% 2.23

5 Technical Note 1: 2010 Base Model

TABLE 1.4 FLOW CALIBRATION – PM PEAK Site Ref Location Anode Bnode Observed Model Diff %diff geh 153 Colne Way, Watford 5057 5038 1188 1053 -135 -11% 4.03 5038 5058 1260 972 -288 -23% 8.62 154 North Western Avenue, 5004 5011 1099 928 -171 -16% 5.37 Garston 5009 5004 1207 1219 12 1% 0.34 155 Watford Road, Leavesden 5050 1020 866 951 85 10% 2.82 1020 5050 1066 1485 419 39% 11.73 156 Watford Road, Langleybury 1020 9017 699 699 0 0% 0.00 9017 1020 832 716 -116 -14% 4.17 206 Rickmansworth Road, 1009 9008 904 880 -24 -3% 0.80 Chorleywood 9008 1009 895 958 63 7% 2.07 207 London Road, Batchworth 3044 9006 1040 1009 -31 -3% 0.97 Heath 9006 3044 794 834 40 5% 1.40 208 Hempstead Road, Watford 5020 5086 1096 927 -169 -15% 5.31 5086 5020 910 638 -272 -30% 9.78 214 St Albans Road, Garston 5055 5017 716 760 44 6% 1.62 5017 5056 740 743 3 0% 0.11 215 St Albans Road, Watford 95022 5043 488 578 90 18% 3.90 5043 95022 449 431 -18 -4% 0.86 216 Scots Hill, Rickmansworth 3014 3008 1087 1156 69 6% 2.06 3008 3014 1167 1103 -64 -5% 1.90 252 Oxhey Lane, Watford 4015 4037 685 605 -80 -12% 3.15 4037 4015 782 722 -60 -8% 2.19 317 Sandy Lane, Eastbury 4022 4032 567 521 -46 -8% 1.97 4032 4022 669 665 -4 -1% 0.15 346 Moor Lane, Batchworth 3017 3010 715 654 -61 -9% 2.33 3010 3017 403 560 157 39% 7.15 351 Prestwick Road, South 94034 4034 569 562 -7 -1% 0.29 Oxhey 4034 94034 476 302 -174 -37% 8.82 453 Horseshoe Lane, Leavesden 5066 5065 414 455 41 10% 1.97 5065 5066 374 296 -78 -21% 4.26 454 High Road, Leavesden 5062 5040 213 21 -192 -90% 17.75 5040 5062 298 245 -53 -18% 3.22 542 Rickmansworth 1011 3009 685 743 58 8% 2.17 3009 1011 1082 1007 -75 -7% 2.32 562 Uxbridge Road, 3013 3003 978 1135 157 16% 4.83 Rickmansworth 3003 3013 731 786 55 8% 2.00

1.17 As shown, some 69% of comparisons in the AM peak achieve a geh of less than 5, with 81% achieving less than 6. In the PM peak, the corresponding values are 78% and 83%.

Conclusion

1.18 Having incorporated updated to the central cordon to the wider model area, the initial comparison of assigned flows to counts did not result in many matches and as such the need for a relatively minor update to the calibration was identified.

1.19 It should be noted that the exercise outlined in this Technical Note represents a flow calibration exercise only, and shouldn’t be regarded as a model upgrade,

6 Technical Note 1: 2010 Base Model

particularly given that no additional information has been gathered on origins and destinations of journeys within the model area.

1.20 However, it is believed that the resulting 2010 base model are provide a suitable base point for the preparation of a transport evidence base to support the LDF consultation process.

7

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Technical Note 1: 2010 Base Model

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 224042/01

ISSUE HISTORY

Issue No. Date Details

1 3 August 2011 Draft

REVIEW

Originator Steve Oliver

Other Contributors

Review by: Print

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

C:\work\Watford Model\Draft Tech Note 1 - 3Aug11.docx

Control Sheet Three Rivers and Watford LDF

Technical Note 2: Future Year Model Development

Technical note December 2011

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall West Riding House Pegs Lane 67 Albion Street Hertford Leeds LS1 5AA SG13 8DN +44 (0)113 389 6400 www.steerdaviesgleave.com

Technical Note 2: Future Year Model Development

CONTENTS

1 TASK 2: FUTURE YEAR MODEL DEVELOPMENT ...... 1 Introduction ...... 1 Scenario Testing ...... 1 Matrix Development ...... 2 Matrix Totals ...... 8 Network Development ...... 9 Conclusions ...... 13

FIGURES

Figure 1.1 AM Peak – Base + Committed Development – Network Delay >120secs ...... 11 Figure 1.2 PM Peak – Base + Committed Development – Network Delay >120 secs ...... 12

TABLES

Table 1.1 Summary of Committed Developments – Three Rivers ...... 2 Table 1.2 Summary of Committed Develpopments - Watford ...... 3 Table 1.3 Summary of Potential Developments – Three Rivers ...... 6 Table 1.4 Summary of Potential Developments - Watford ...... 7 Table 1.5 TeMpro Growth 2010-2016 – Car Driver Trips ...... 8 Table 1.6 Future Year Matrix Totals ...... 9

APPENDICES

A COMMITTED DEVELOPMENTS B HEALTH CAMPUS / WIGGENHALL ROAD JUNCTION LAYOUT

Contents

Technical Note 2: Future Year Model Development

1 Task 2: Future Year Model Development

Introduction

1.1 Following agreement of 2010 Base Model as defined in Technical Note 1, this second technical note sets out how the committed and proposed developments have been assigned to the Watford SATURN Model and identifies the impacts upon the highway network.

1.2 This stage of the evaluates the level of traffic forecast to be generated by sites identified as committed developments in each of the Three Rivers and Watford areas and seeks to identify any network improvements, some of which are also committed, that are likely to be required to support committed growth.

1.3 Except where committed infrastructure proposals are identified, such improvements to the network are constrained to relatively modest upgrades, which we believe can be delivered within existing highway boundaries.

1.4 This network will then form the basis for Task 3, where the additional impact of potential sites identified through the LDF process are evaluated.

Scenario Testing

1.5 Whilst the impact of further potential LDF sites will be addressed in more detail in Technical Note 3, there follows a list of scenarios that will be modelled, and the preparation of matrices containing trip forecasts for potential LDF sites is outlined in this note.

1.6 Scenario testing has been carried out to establish the impacts of committed and potential development upon the highway network. These tests include the following combined traffic elements:

I base traffic flows, I committed development flows I potential development flows’ and I background growth to 2026 Tempro equivalents. 1.7 These elements are the added together to produce scenario tests for 2026 as follows:

I Base + committed developments to 2026 I Base + committed developments + background growth to 2026 I Base + committed + potential developments + background growth to 2026 1.8 Target traffic levels in 2026 are derived from the application of background growth rates to the 2010 base traffic flows. Following the addition of committed and potential development, background growth is adjusted to account for the ‘gap’ between identified development and the 2026 target levels.

1.9 The future year of 2026 has been taken to correspond with the Three Rivers LDF timetable. Given that the difference in flows to 2031 would be slight, it is assumed the modelling results remain relevant to Watford who are working towards 2031.

1 Technical Note 2: Future Year Model Development

Matrix Development

Committed Development 1.10 The table below lists the committed developments identified within the Three Rivers district and provides the development size, type and generated trip forecasts. The table also identifies the model zone number to which trips are added. Where available, trip forecasts have been taken directly from the individual development Transport Assessments (TAs). Where such information isn’t available, residential trip rates are derived from those TAs that are available for similar developments, with rates extracted from the TRICS database for other land uses. The following generic rates are applied.

I Housing (per dwg): AM In=0.17, AM Out=0.41, PM In=0.38, PM out=0.23 I B2/B2 (per 100m2): AM In=0.456, AM Out=0.094, PM In=0.044, PM out=0.339 I Office (per 100m2): AM In=1.483, AM Out=0.172, PM In=0.139, PM out=1.235 I Retail (per 100m2): AM In=9.311, AM Out=6.580, PM In=7.883, PM out=11.173 I Hotel (per bed): AM In=0.091, AM Out=0.113, PM In=0.097, PM out=0.084

TABLE 1.1 SUMMARY OF COMMITTED DEVELOPMENTS – THREE RIVERS

Zone Development Units Generated Trips Size AM in AM Out PM In PM Out

Abbots Langley

103 33 Residential Units 6 13 12 7

Carpenders Park

222 33 Residential Units 5 14 13 7 (inc Rear of Kebbel House)

Chorleywood

311 54 Residential Units 9 22 20 12

Croxley Green

331 204 Residential Units 35 83 76 47 (inc Old Merchant Taylors and Durrants)

Moor Park and Eastbury

342 37 Residential Units 6 15 14 8

2 Technical Note 2: Future Year Model Development

Kings Langley

84 4 Residential Units 1 2 2 1

Rickmansworth

325 110 Residential Units 15 38 35 20 (inc 3a High St)

South Oxhey

221 31 Residential Units 5 13 12 7

Leavesden

447 425 Residential Units 72 173 160 96

447 Studio Studio Tours 33 2 137 168

Total Generated Trips 187 375 481 373

1.11 The total generated trips amounted to an additional 562 two-way trips in AM modelled period and 854 in the PM modelled period.

1.12 Similarly, the table below identifies the number of trips generated from the committed developments within the Watford. Again, where available, trip forecasts are taken directly from individual development Transport Assessments, otherwise the generic trip rates set out above are applied.

TABLE 1.2 SUMMARY OF COMMITTED DEVELPOPMENTS - WATFORD

Zone Development Units Generated Trips Size AM in AM Out PM In PM Out

Leggatts Ward

122 232 Residential Units (inc 31 79 72 31 Leggatts Campus)

121 -7 Residential Units -1 -3 -3 -2

Vicarage Ward

435 74000 Health Campus - 923 216 183 553 Hospital (sqm)

435 5005 Health Campus - 0 0 106 83 Restaurant (sqm)

435 14715 Health Campus - 53 65 64 37 Hotel (sqm)

3 Technical Note 2: Future Year Model Development

435 18780 Health Campus - 281 34 28 234 Offices (sqm)

436 85 Health Campus - 7 21 17 9 Residential Units

448 419 Health Campus - 34 96 90 46 Residential Units

434 26 Residential Units 4 11 10 6

436 5 Residential Units 1 2 2 1

437 17 Residential Units 3 7 6 4

Woodside Ward

111 73 Residential Units 9 20 19 11

Callowland Ward

121 65 Residential Units 11 26 25 15

Central Ward

121 24 Residential Units 4 10 9 6

412 69 Residential Units 12 28 26 16

414 63 Residential Units 6 15 10 10

416 199 Residential Units 31 79 74 43

417 58 Residential Units 10 24 22 13

418 6 Residential Units 1 2 2 1

419 1 Residential Units 0 0 0 0

Holywell Ward

213 1 Residential Units 0 0 0 0

333 14 Residential Units 2 6 5 3

437 98 Residential Units 17 40 37 22

438 6 Residential Units 1 2 2 1

Meriden Ward

131 167 Residential Units 25 65 66 43

Nascot Ward

122 3 Residential Units 0 1 1 0

4 Technical Note 2: Future Year Model Development

401 37 Residential Units 37 83 72 50

411 69 Residential Units 12 28 26 16

422 223 Residential Units 4 10 9 6

Oxhey Ward

211 69 Residential Units 12 28 26 16

421 5 Residential Units 1 2 2 1

422 62 Residential Units 1 3 3 2

Park Ward

402 10 Residential Units 2 4 4 2

411 1 Residential Units 0 0 0 0

433 7 Residential Units 1 3 3 2

437 7 Residential Units 1 3 3 2

Stanborough Ward

112 34 Residential Units 6 14 13 8

Tudor Ward

132 9 Residential Units 2 4 3 2

Total Generated Trips 1544 1028 1035 1294

1.13 For Watford, the total generated trips amount to an additional 2573 two-way trips in AM modelled period and 2329 in the PM modelled period.

1.14 For both Three Rivers and Watford, more detailed information relating to committed developments is provided in Appendix A.

Update Methodology 1.15 There is a two stage process for adding new trips outlined in Tables 1.1 and 1.2 to the base matrices for the AM and PM peaks.

1.16 Where a Transport Assessment, or previous analysis, has identified a specific distribution pattern associated with a particular development, individual trip matrices for those developments are created. This applies to the following sites:

I Health Campus I Leavesden Studios 1.17 For increases in trips to and from all other zones where committed development will occur, proportional increases in base year trip levels for those relevant zones are calculated, and the resulting factor applied to corresponding row and column totals. By default, this assumes that trips to and from developments without their

5 Technical Note 2: Future Year Model Development

own distribution patterns will correspond to zonal distributions in the base matrices.

1.18 The base matrices are factored as described, and then the individual development matrices are added to produce the ‘Base + Committed Developments to 2026’ matrices.

1.19 Committed development trips are added as a separate user class (User Class 2), so that traffic on the network can be distinguished between base and committed.

Potential Development 1.20 Sites identified for potential development, beyond those already committed, have been identified for both Three Rivers and Watford. The following tables provide a summary of developments and the forecast numbers of generated trips (added as User Class 3). In Three Rivers future housing allocations are identified across seven wards. For Watford, potential development is focussed mainly on the town centre and Watford Business Park.

TABLE 1.3 SUMMARY OF POTENTIAL DEVELOPMENTS – THREE RIVERS

Zone Development Units Generated Trips Size AM in AM PM In PM Out Out

Abbots Langley

101 15 Residential Units 3 6 6 3

103 60 Residential Units 10 24 23 14

Croxley Green

331 60 Residential Units (inc 10 24 23 14 Killingdown Farm)

333 35 Residential Units –Former 6 14 13 8 Croxley Green Station

431 50 Residential Units – South 9 20 19 11 Tolpits Lane

Langleybury

84 235 Residential Units (inc 40 95 88 53 Kings Langley)

105 75 Residential Units – 13 30 28 17 Langleybury House

Leavesden

51 50 Residential Units – 9 20 19 11 Waterdell, Brickett Wood

6 Technical Note 2: Future Year Model Development

102 30 Residential Units – Hill 5 12 11 7 Farm Industrial Estate

Rickmansworth

31 10 Residential Units 2 4 4 2

325 253 Residential Units (inc 43 103 95 57 Long Island Exchange & Stockers Farm Road)

351 16000 sqm B2/B8 Employment – 73 15 7 63 Maple Lodge, Maple Cross

Sarratt

301 10 Residential Units 2 4 4 2

South Oxhey

221 473 Residential Units (inc 81 192 178 107 Little Furze School, Land South of St Josephs, South Oxhey Town Centre Regeneration & Heysham Drive)

Total Generated Trips 304 566 516 370

TABLE 1.4 SUMMARY OF POTENTIAL DEVELOPMENTS - WATFORD

Zone Development Description Generated Trips Size & units AM in AM PM In PM Out Out

Central

142 Watford Junction Station

1200 dwgs Residential – 204 487 451 272

350 Phases 1&2 850 Phase 3&4

23225 sqm Offices – 344 40 32 287

4645m2 Phases 1&2 18580 m2 Phases 3&4

300 bed Hotel 27 34 29 25

7 Technical Note 2: Future Year Model Development

413/ 56458 sqm Town Centre (net 71 11 277 393 440 increase)

433 96 dwgs Metropolitan Station 16 39 36 22 Approach

Holywell

304 3716 sqm Western Gateway (net 346 245 293 415 increase – retail)

Total Generated Trips 1010 856 1117 1413

1.21 The same update methodology as derived for committed trips, in terms of factors applied to appropriate row and column totals, is adopted. Trips associated with potential development are added as User Class 3.

Background Growth 1.22 The Tempro (v6.2) database has been interrogated to identify the expected growth in car driver trips between the years of 2010 and 2026. The average of origin and destination growth is used. Furthermore, there are differences in predicted growth between Watford and Three Rivers and, as such, growth rates for Hertfordshire is applied which is slightly below growth for Watford and a little above growth for Three Rivers. Given the coverage of model area, this seems reasonable. The output is shown in Table 1.5.

TABLE 1.5 TEMPRO GROWTH 2010-2026 – CAR DRIVER TRIPS

Region/District Time Growth Factors Period Origin Destination Average

Hertfordshire AM 1.134 1.150 1.142

PM 1.153 1.135 1.144

Watford AM 1.138 1.165 1.151

PM 1.159 1.134 1.146

Three Rivers AM 1.084 1.109 1.096

PM 1.107 1.085 1.096

Matrix Totals

1.23 Before adding growth rates to calculate the target number of trips for 2026, existing baseline trips at the Health Campus are removed to avoid any double counting when the new trips associated with the redevelopment are added. The 2026 target is then maintained as a fix against which factors for residual growth, not accounted for by committed and/or potential developments, can be calculated. The process is outlined in the following steps:

8 Technical Note 2: Future Year Model Development

I Base matrix total AM: 52396 PM: 55744 I After Health Campus Adjustment AM: 50925 PM: 54829 I 2010-2026 Growth (Tempro) AM: 1.142 PM: 1.144 I 2026 Trip Target AM: 58157 PM: 62725 I Committed Trips (UC2) AM: 3104 PM: 3150 I Potential Trips (UC3) AM: 2742 PM: 3428

I Base + Committed AM: 54029 PM: 57979 I Shortfall at 2026 AM: 4128 PM: 4745 I Residual Growth Factor AM: 1.081 PM: 1.087

I Base + Committed + Potential AM: 56771 PM: 61407 I Shortfall at 2026 AM: 1386 PM: 1318 I Residual Growth Factor AM: 1.027 PM: 1.024 1.24 Tables 1.6 now provides a breakdown of matrix total by user class. The small discrepancy between the target totals set out above and the matrix totals is explained by rounding of the base growth scaling factors.

TABLE 1.6 FUTURE YEAR MATRIX TOTALS

Matrix Scenario 2026 Total

UC1 UC2 UC3

AM: Base + Committed 50925 3104 - 54029

AM: Base + Committed + Growth 55050 3104 - 58154

AM: Base + Committed + Potential + Growth 52300 3104 2742 58146

PM: Base + Committed 54829 3150 - 57979

PM: Base + Committed + Growth 59600 3150 - 62749

PM: Base + Committed + Potential + Growth 56145 3150 3428 62723

Network Development

1.25 Before assigning the 2026 matrices to the model, the following network improvements are assumed:

I Health Campus Link . Connecting Dalton Way to the Health Campus site via Wiggenhall Road . Left-in/left-out junction provided at Dalton Way (one-way operation) . New signalised junction with Wiggenhall Road: Layout shown in Appendix B

I Colonial Way Extension . Connecting Colonial Way from its junction with Imperial Way to St Albans Rd . All moves signalised junction with St Albans Lane

9 Technical Note 2: Future Year Model Development

. New rear entrance to Watford Junction Station car parks, forming a new signalised junction with Colonial Way Extension

1.26 Initial assignment of the ‘Base+Committed’ matrices identified a number of areas where stress on the network, in terms of queues and delays, are increased significantly over the 2010 base scenario. An assessment of each location has been carried out to make a judgement as to whether increased capacity could realistically be delivered to accommodate additional levels of traffic associated with the committed development. It seems reasonable to assume that developers of those committed schemes will be expected to contribute in some way to network improvements.

1.27 In some cases, improvements are delivered through optimisation of traffic signals. However, where increased physical capacity is required, solutions are constrained through a broad assessment of land availability, although it must be stressed that a more detailed assessment would be required if any of the schemes proposed were to be progressed. A summary of additional changes made to the network to accommodate committed development is provided below.

I Coding of additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre (Node 3005) I Provision of additional right turn lanes into and out of Glen Way (Node 5103) and Grove Mill Lane (Node 5020) at their junctions with A411 Hempstead Road I Traffic signal optimisation at junction of Clarendon Rd/St Johns Rd (Node 6044) I Traffic signal optimisation at junction of Hempstead Rd/Langley Way (Node 5021) I Traffic signal optimisation at junction of Exchange Rd/Market St (Node 6013) 1.28 Figure 1.1 shows delay on the network for the AM peak. The plot is restricted to delays in excess of 120 seconds only. As shown, there remains some delay on the approach to Rickmansworth from the west and north in the morning peak, along with modest delays in Leavesden and the St Albans Road/Station Road junction, as well as on the approach to Eastbury Road at its signalised junctions with Brookdene Avenue and Deacons Hill.

1.29 Figure 1.2 shows the same for the PM peak. While delay at around Rickmansworth and in Leavesden is not predicted for the PM peak, there remains delay at the Eastbury Road/ Deacons Hill junction and at various locations along Hempstead Road, despite the improvements proposed for various junctions along this route.

1.30 As such, despite modest updates to the network to accommodate the worst of the delay the in the Base+Committed scenario, operation of the junction of Eastbury Road/Deacons Hill is likely to be cause for concern in future years, with increased delay also predicted on the approach to Rickmansworth in the morning peak and along Hempstead Road in the evening peak.

1.31 This network (AM and PM) becomes the base network for future tests at 2026.

10 Technical Note 2: Future Year Model Development

FIGURE 1.1 AM PEAK – BASE + COMMITTED DEVELOPMENT – NETWORK DELAY >120SECS

11 Technical Note 2: Future Year Model Development

FIGURE 1.2 PM PEAK – BASE + COMMITTED DEVELOPMENT – NETWORK DELAY >120 SECS

12 Technical Note 2: Future Year Model Development

Conclusions

1.32 Committed development sites in both the Three Rivers district and in Watford have been identified and associated forecasts of trip generation indicate that we expect to be adding some 3104 2-way trips to the model network in the AM peak, and a similar increase of 3150 in the PM peak.

1.33 Committed development includes the Health Campus proposals and, as such, the network includes the new Health Campus link road from Dalton Way via a new signalised junction with Wiggenhall Road. In addition, it is assumed that Colonial Way Extension will be delivered by 2026.

1.34 Assigning ‘Base+Committed’ demand to the updated network identified other locations where it appears feasible that capacity improvements could be implemented to help accommodate additional demand associated with committed development. These include optimisation of traffic signals at a number of junctions, physical changes to the network at junctions along Hempstead Road and additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre.

1.35 With the network improvements identified, it is predicted that operation of the junction of Eastbury Road/Deacons Hill is likely to be cause for concern in future years, with increased delay also predicted on the approach to Rickmansworth in the morning peak and along Hempstead Road in the evening peak.

Filenames I AM peak . Network: AM26NET_networkupdate3B.dat . Matrix: AM_base+committed.ufm

I PM Peak . Network: PM26NET_networkupdate4.dat . Matrix: PM_base+committed.ufm

13

Technical Note 2: Future Year Model Development

APPENDIX

A

COMMITTED DEVELOPMENTS

Appendix A

Residential Commitments and Completions by ward2kbarnesrept

Borough/District Name Watford

Res Commitment Between Between 01/04/2010 and 31/03/2011

PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

Borough/District Name Watford

- Site Ref 18281

230 13

---- Ward Name Leggatts Ward

09/00835/FUL Former West Redevelopmen New residential building Y 0.000 21/07/2010 21/07/2013 31/03/2011 217 66 1 0 0 0 -1 0 0 0 -1 0 217 66 217 66 Full STARTED Herts College, t of college site Leggatts Campus, for 217 Leggatts Way, dwellings & Watford, WD24 neighbourhood 5TE centre

Leggatts Ward Totals: 0.000 217 66 1 0 0 0 -1 0 0 0 -1 0 217 66 217 66

18281 Totals: 0.000 217 66 1 0 0 0 -1 0 0 0 -1 0 217 66 217 66

- Site Ref 18282

504 0

---- Ward Name Vicarage Ward

07/00958/OUTM Watford General Mixed use New residential building Y 26.400 15/07/2010 15/07/2020 504 176 0 0 0 0 0 0 0 0 0 0 504 176 504 176 Outline GRANTED Hospital, Vicarage health campus Road, Watford

Vicarage Ward Totals: 26.400 504 176 0 0 0 0 0 0 0 0 0 0 504 176 504 176

18282 Totals: 26.400 504 176 0 0 0 0 0 0 0 0 0 0 504 176 504 176

- Site Ref 2511

148 -9

---- Ward Name Woodside Ward

10/00152/FULM Betrita, North Demolition of New residential building Y 0.408 13/05/2010 13/05/2013 17 0 1 0 0 0 -1 0 0 0 -1 0 17 0 17 0 Full GRANTED Orbital Road, dwelling & Watford, WD25 erection of 17 0NB dwellings 11/00057/FULM Elm Cot, North Erection of 11 New residential building Y 0.299 31/03/2011 31/03/2014 11 0 1 0 0 0 0 0 0 0 0 0 11 0 10 0 Full GRANTED Orbital Road, dwellings Watford, WD25 0NB Woodside Ward Totals: 0.707 28 0 2 0 0 0 -1 0 0 0 -1 0 28 0 27 0

2511 Totals: 0.707 28 0 2 0 0 0 -1 0 0 0 -1 0 28 0 27 0

- Site Ref Not on a Site

0 0

---- Ward Name Callowland Ward

10/00182/FUL 166, Leavesden Amendments New residential building Y 0.000 13/05/2010 13/05/2013 31/03/2011 31/03/2011 2 0 0 0 2 0 2 0 2 0 2 0 0 0 0 0 Full COMPLET Road, Watford, to extant ED WD24 5EG permission 08/00828 to convert 1 flat into 2 flats 10/00409/FUL Garage Block &, Demolition of New residential building Y 0.000 10/06/2010 10/06/2013 31/03/2011 6 0 0 0 0 0 0 0 0 0 0 0 6 0 6 0 Full STARTED Land adj, garages & Copsewood Road erection of 6 &, Bedford Street, dwellings Watford (amended scheme) 10/00442/FUL Flat 3, 190, St Conversion of Conversion of existing Y 0.090 10/06/2010 10/06/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Albans Road, flat into 2 flats dwelling(s) Watford, WD24 4AS 10/00605/EXT 225, St Albans Renewal of Conversion of existing Y 0.000 19/08/2010 19/08/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, 07/00596/FUL dwelling(s) WD24 5BH for conversion of loft to 1 flat

10/00663/FULM Callowland Place, Erection of 16 New residential building Y 0.330 02/12/2010 02/12/2013 16 16 0 0 0 0 0 0 0 0 0 0 16 16 16 16 Full GRANTED Callowland Close, dwellings Watford, WD24 5LU

10/00757/FUL 376, St Albans Extension & Conversion of existing Y 0.019 29/09/2010 29/09/2013 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Road, Watford, conversion to dwelling(s) WD24 6PJ create 2 additional flats PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

11/00090/EXT 81, Regent Street, Conversion of Conversion of existing Y 0.010 10/03/2011 10/03/2014 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford, WD24 1 dwelling into dwelling(s) 5AT 2 dwellings

9000609 42 Gammons Extension & Unknown Y 0.038 02/03/2009 02/03/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Lane, Watford conversion into 2 dwellings

9001708 215 St Albans Conversion of Unknown Y 0.015 29/02/2008 28/02/2011 4 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Road, Watford 1 dwelling into 4 flats 9010208 Garage Block & Erection of 5 Unknown Y 0.173 15/04/2009 15/04/2012 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Adj Land, dwellings DED Copsewood Road & Bedford Street, Watford 9020108 81 Regent Street, Conversion of Unknown Y 0.010 24/04/2008 24/04/2011 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford 1 dwelling into DED 2 dwellings

9021709 Land R/O 208- Erection of 3 Unknown Y 0.009 14/05/2009 14/05/2012 31/03/2011 3 0 0 0 0 0 0 0 0 0 0 0 3 0 3 0 Full STARTED 210 St Albans flats Road, Watford 9033508 56 Bedford Street, Conversion of Unknown Y 0.053 26/06/2008 26/06/2011 31/03/2009 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full STARTED Watford dwelling into 3 flats 9047408 226-228 St pt. demolition Unknown Y 0.027 13/06/2008 13/06/2011 31/03/2010 31/03/2011 2 0 0 0 2 0 2 0 2 0 2 0 0 0 0 0 Full COMPLET Albans Road, & extension to ED Watford shop & cou of upper floors from offices to 2 flats

9050409 R/O 164 St conversion of Unknown Y 0.005 02/11/2009 02/11/2012 31/03/2011 31/03/2011 2 0 0 0 2 0 2 0 2 0 2 0 0 0 0 0 Full COMPLET Albans Road, unauthorised 3 ED Watford flats into 2 flats

9052809 Former Bus part demolition Unknown Y 0.151 07/10/2009 07/10/2012 21 0 0 0 0 0 0 0 0 0 0 0 21 0 21 0 Full GRANTED Garage, At Corner & Of Copsewood redevelopment Road & for offices & 21 Leavesden Road, flats Watford

9056705 436 St Albans Conversion of Unknown Y 0.021 15/08/2005 15/08/2010 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Road, Watford 1 dwelling into 2 flats 9059607 225 St Albans conversion of Unknown Y 0.008 27/06/2007 27/06/2010 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Road, Watford loft into 1 flat DED

9078309 5 Maude Extension & Unknown Y 0.026 30/11/2009 30/11/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Crescent, Watford conversion of dwelling into 2 flats 9082808 166 Leavesden Demolition of Unknown Y 0.043 04/09/2008 04/09/2011 31/03/2010 31/03/2011 9 0 0 0 8 0 8 0 8 0 8 0 0 0 0 0 Full COMPLET Road, Watford dental surgery ED & erection of 9 flats

9095208 Ground Floor, Part cou from Unknown Y 0.010 27/08/2008 27/08/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Watford A2 to dwelling

9097209 1 Copsewood Conversion of Unknown Y 0.012 08/01/2010 08/01/2013 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Road, Watford 1 dwelling into ED 2 flats 9097708 266-268 St Cou of first & Unknown Y 0.037 04/09/2008 04/09/2011 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Albans Road, second floors Watford from retail to 4 flats 9127008 188-196 St Erection of 2 Unknown Y 0.006 14/07/2009 14/07/2012 31/03/2011 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full STARTED Albans Road, flats Watford 9146108 1 Lea Road, Conversion of Unknown Y 0.032 04/02/2009 04/02/2012 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Watford 1 house into 3 flats 9146608 70 Leavesden cou from job Unknown Y 0.008 20/01/2009 20/01/2012 0 0 1 0 0 0 0 0 0 0 0 0 0 0 -1 0 Full GRANTED Road, Watford related flat to hair / beauty salon 9161606 224 St Albans extension & Unknown Y 0.014 09/02/2007 09/02/2010 31/03/2008 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full STARTED Road, Watford conversion of 1 flat into 3 flats

9172107 2 Southwold Conversion of Unknown Y 0.009 13/02/2008 13/02/2011 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Road, Watford 1 dwelling into 2 dwellings

Callowland Ward Totals: 1.156 107 16 14 0 16 0 15 0 16 0 15 0 74 16 65 16

---- Ward Name Central Ward

09/00540/FULM 35/37, Demolition of 2 New residential building Y 0.000 08/04/2010 08/04/2013 17 0 0 0 0 0 0 0 0 0 0 0 17 0 17 0 Full GRANTED Marlborough HMOs & Road, Watford, erection of 17 WD18 0QD flats 10/00121/EXT 52a - 56, High Redevelopmen New residential building Y 0.164 04/06/2010 04/06/2015 56 17 0 0 0 0 0 0 0 0 0 0 56 17 56 17 Demolitio GRANTED Street, Watford, t to provide 56 n WD17 2EF flats & retail

10/00166/FUL 17a, Westland Demolition of New residential building Y 0.042 17/11/2010 17/11/2013 5 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Road, Watford, dwelling & DED WD17 1QR erection of 5 flats PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

10/00252/EXT 58-68, The Renewal of Change of use of non-res Y 0.000 10/06/2010 10/06/2013 13 0 0 0 0 0 0 0 0 0 0 0 13 0 13 0 Full GRANTED Parade, High planning building to dwelling(s) Street, Watford, permission WD17 1AH 07/00395/FUL M for cou of 1st & 2nd floors to 13 flats 10/00344/FUL 31-33, Woodford Demolition of New residential building Y 0.000 18/06/2010 18/06/2013 9 0 0 0 0 0 0 0 0 0 0 0 9 0 9 0 Full GRANTED Road, Watford, light industrial WD17 1PB building & erection of 9 flats 10/00381/FUL 178, Queens Extension & Change of use of non-res Y 0.011 16/06/2010 16/06/2013 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Road, Watford, conversion of building to dwelling(s) WD17 2NT HMO to 2 flats

10/00385/FULM 132-136a High Redevelopmen Change of use of non-res Y 0.289 19/07/2010 19/07/2013 24 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Street, 3-9 King t & part building to dwelling(s) DED Street, 13 Smith conversion to Street, Watford, provide retail, WD17 2EN restaurants & 24 flats 10/00412/FUL 46, Kings Close, Retrospective Conversion of existing Y 0.000 21/06/2010 21/06/2010 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Watford, WD18 conversion of dwelling(s) ED 0UB dwelling into 2 dwellings 10/00722/FULM 14, Rosslyn Road, Demolition of New residential building Y 0.000 02/09/2010 02/09/2013 11 0 0 0 0 0 0 0 0 0 0 0 11 0 11 0 Full GRANTED Watford, WD18 HMO & 0JY erection of 11 flats 10/00823/FUL 96a, Queens Demolition of Conversion of existing Y 0.010 20/10/2010 20/10/2013 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Road, Watford, shed & dwelling(s) WD17 2NX conversion of dwelling into 3 flats 10/00870/FUL 17A, Westland DEMOLITION New residential building Y 0.042 16/12/2010 16/12/2013 5 0 1 0 0 0 0 0 0 0 0 0 5 0 4 0 Full GRANTED Road, Watford, OF WD17 1QR DWELLING & ERECTION OF 5 FLATS 10/00897/FUL 75, Queens Road, Conversion of Change of use of non-res Y 0.019 22/11/2010 22/11/2013 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Watford, WD17 dwelling into 2 building to dwelling(s) 2QN flats. Cou from retail to dwelling

10/00908/FUL 4a, Smith Street, Demolition of New residential building Y 0.025 17/11/2010 17/11/2013 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Watford, WD18 commercial 0AA garage & workshop & erection of 4 flats 10/00915/FUL 2, Monmouth Conversion of Conversion with Extension Y 0.020 10/11/2010 10/11/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Demolitio GRANTED Road, Watford, loft space into n WD17 1QN flat 10/00926/COU 15, St Johns Cou of part of Change of use of non-res Y 0.007 22/11/2010 22/11/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, ground floor & building to dwelling(s) WD17 1PU 1st & 2nd floor to masionette

10/01145/FUL 9, The Parade, Conversion of Change of use of non-res Y 0.030 10/01/2011 10/01/2014 31/03/2011 31/03/2011 6 0 0 0 6 0 6 0 6 0 6 0 0 0 0 0 Full COMPLET High Street, existing building to dwelling(s) ED Watford, WD17 redundant 1LQ office space above retail unit to provide 6 no. dwellings, consisting of 2 no.studio flats and 4 no. 1 bed flats.

10/01157/FUL 68, Sutton Road, Conversion of Conversion of existing Y 0.016 20/01/2011 20/01/2014 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Watford, WD17 HMO into 2 dwelling(s) 2QQ flats 10/01214/FULM 24-28, St Albans Redevelopmen New residential building Y 0.121 17/02/2011 17/02/2014 24 0 0 0 0 0 0 0 0 0 0 0 24 0 24 0 Full GRANTED Road, Watford t for 24 flats & offices 10/01236/FULM 132-136a High Redevelopmen Change of use of non-res Y 0.289 10/03/2011 20/03/2014 24 0 5 0 0 0 0 0 0 0 0 0 24 0 19 0 Full GRANTED Street, 3-9 King t & part building to dwelling(s) Street, 13 Smith conversion to Street, Watford, provide retail, WD17 2EN restaurants & 24 flats 10/01241/COU 91, Market Street, Erection of 1st Conversion with Extension Y 0.006 08/02/2011 08/02/2014 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Watford, WD18 floor extension 0PT on existing outbuilding & cou to create dwelling

9000208 51a Market Street, Conversion of Unknown Y 0.015 27/02/2008 27/02/2011 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Watford 1 dwelling into 2 dwellings (upper floors)

9001407 37c St Johns demolition of Unknown Y 0.070 12/04/2007 12/04/2010 5 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Outline LAPSED Road, Watford dwelling & erection of 5 flats 9006209 49 Water Lane, Conversion of Unknown Y 0.004 14/05/2009 14/05/2012 31/03/2010 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Watford basement into ED flat PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9019506 26 Exchange redevelopment Unknown Y 0.360 18/05/2006 18/05/2009 31/03/2007 31/03/2011 134 40 0 0 134 40 134 40 134 40 134 40 0 0 0 0 Full COMPLET Road, Watford to provide ED commercial use & 134 flats

9023309 78a Queens Conversion of Unknown Y 0.024 11/05/2009 11/05/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford 1st & 2nd floors into 2 flats 9030009 R/O 80 Queens Erection of 2 Unknown Y 0.011 16/06/2009 16/06/2012 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Road, Watford dwellings

9034308 14 Rosslyn Road, Demolition of Unknown Y 0.069 16/05/2008 16/05/2011 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford HMO & DED erection of 9 flats 9039507 58-68 The COU of 1st & Unknown Y 0.081 14/06/2007 14/06/2010 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Parade, High 2nd floors from DED Street, Watford offices into 13 flats 9046708 87-89 Market COU of 1st & Unknown Y 0.033 22/05/2008 22/05/2011 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Street, Watford 2nd floors from offices to 2 flats & erection of 2 additional flats at rear

9053200 28 Market Street, COU OF 1ST Unknown Y 0.007 14/02/2001 14/02/2006 31/03/2007 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full STARTED Watford & 2ND FLOORS FROM OFFICES TO 2 FLATS 9057109 91 Market Street, Erection of Unknown Y 0.006 07/09/2009 07/09/2012 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford dwelling DED

9061108 84 & 84a Queens Conversion of Unknown Y 0.021 12/08/2008 12/08/2011 5 0 1 0 0 0 0 0 0 0 0 0 5 0 4 0 Full GRANTED Road, Watford upper floors from 1 flat into 3 flats & erection of 2 dwellings at rear

9064608 136a High Street, Demolition of Unknown Y 0.023 23/06/2008 23/06/2011 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford retail & DED erection of A3 restaurant and 2 flats. 9066008 45 Gladstone Cou to HMO Unknown Y 0.018 23/12/2008 23/12/2011 31/03/2009 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Road, Watford (retrospective)

9066108 24-26 Market Cou from retail Unknown Y 0.025 25/09/2008 25/09/2011 6 0 0 0 0 0 0 0 0 0 0 0 6 0 6 0 Full GRANTED Street, Watford to restaurant & wine bar with 6 flats on upper floors

9074608 Rainbow House, demolition of Unknown Y 0.128 16/12/2009 16/12/2012 31/03/2011 62 62 0 0 0 0 0 0 0 0 0 0 62 62 62 62 Full STARTED 24 Water Lane, offices & Watford auction rooms & erection of 62 flats

9075509 6a Market Street, upper floor Unknown Y 0.020 10/12/2009 10/12/2012 31/03/2010 3 0 1 0 0 0 -1 0 0 0 0 0 3 0 3 0 Full STARTED Watford extension & conversion to 3 flats 9078109 30 Westland demolition of Unknown Y 0.043 07/01/2010 07/01/2013 12 0 0 0 0 0 0 0 0 0 0 0 12 0 12 0 Full GRANTED Road, Watford hotel & erection of 12 flats 9080209 9 The Parade, cou of upper Unknown Y 0.029 18/12/2009 18/12/2012 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE High Street, floors from DED Watford bank to 6 flats

9082709 137-139 Queens Part Change of use of non-res Y 0.056 27/01/2010 27/01/2013 31/03/2010 8 0 2 0 0 0 -2 0 0 0 0 0 8 0 8 0 Full STARTED Road, Watford demolition, building to dwelling(s) extension & COU from shop, workshop & office to 3 flats and conversion of 2 flats into 5 flats

9089308 6 Duke Street, Conversion of Unknown Y 0.021 12/08/2008 12/08/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1 dwelling into 2 dwellings

9091308 132 High Street, COU from Unknown Y 0.012 13/08/2008 13/08/2011 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford bank to flat DED 9091708 49 Water Lane, Conversion of Unknown Y 0.012 17/09/2008 17/09/2011 31/03/2009 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford 1 dwelling into 2 flats 9093309 148 High Street, Erection of Unknown Y 0.017 28/01/2010 28/01/2013 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Watford offices & 2 flats

9102908 148 Queens Demolition of Unknown Y 0.057 23/09/2008 23/09/2011 31/03/2011 11 0 0 0 0 0 0 0 0 0 0 0 11 0 11 0 Full STARTED Road, Watford car hire office & erection of replacement office & 11 flats

9127306 22 St Johns Road, conversion of 1 Unknown Y 0.016 11/07/2007 11/07/2010 31/03/2009 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford dwelling into 2 flats PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9133506 52a-56 High redevelopment Unknown Y 0.164 18/05/2007 18/05/2010 56 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Street, Watford to provide retail DED & 56 flats

9139807 Watford Springs, Erection of 129 Unknown Y 1.115 05/06/2008 05/06/2011 31/03/2010 129 42 0 0 14 0 14 0 14 0 14 0 115 42 115 42 Full STARTED Lower High Street, dwellings Watford 9144708 11 King Street, Cou from shop Unknown Y 0.015 16/01/2009 16/01/2012 4 0 1 0 0 0 0 0 0 0 0 0 4 0 3 0 Full GRANTED Watford to flat, formation of additional flat & conversion of masionette into 2 flats 9147308 31 Gladstone Conversion of Unknown Y 0.020 20/07/2009 20/07/2012 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Road, Watford 1 dwelling into 3 dwellings

9147607 1 Bridge Place, conversion of 1 Unknown Y 0.008 19/12/2007 19/12/2010 31/03/2008 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford dwelling into 2 flats 9149708 R/O 101 The Redevelopmen Unknown Y 0.018 22/04/2009 22/04/2012 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Parade, Watford t of land to provide retail, office and residential 9154108 60-62 Queens Extension & Unknown Y 0.054 19/02/2009 19/02/2012 13 0 4 0 0 0 0 0 0 0 0 0 13 0 9 0 Full GRANTED Road, Watford conversion of retail & 4 flats to form new retail space & 6 flats. Erection of 7 flats 9167107 132-136a High St, part Change of use of non-res Y 0.255 13/03/2008 13/03/2011 24 0 5 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE 3-9 King St, 13 redevelopment building to dwelling(s) DED Smith St, Watford , part conversion to provide retail, restaurants & 22 flats (8 conv/COU.) Central Ward Totals: 3.918 745 178 37 0 157 40 153 40 157 40 156 40 440 121 420 121

---- Ward Name Holywell Ward

10/00382/FUL 43, Kings Conversion of Conversion with Extension Y 0.038 07/07/2010 07/07/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Georges Avenue, dwelling into 2 Watford, WD18 dwellings 7QE

10/00537/COU 290, Whippendell COU of ground New residential building Y 0.011 27/07/2010 27/07/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, floor from A1 to WD18 7PD A5. Erection of dwelling

10/00561/FUL 526, Whippendell Erection of Conversion of existing Y 0.020 03/08/2010 03/08/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford, extension & dwelling(s) WD18 7QN conversion of dwelling into 2 flats 10/00796/FUL 131, Hagden Conversion of Change of use of non-res Y 0.013 08/10/2010 08/10/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, 1st floor HMO building to dwelling(s) WD18 7SR into 1 flat

9012608 1-5 Tolpits Lane Demolition of Unknown Y 0.123 24/04/2008 24/04/2011 16 0 2 0 0 0 0 0 0 0 0 0 16 0 14 0 Outline GRANTED &, Watford vehicle sales & repair & 2 flats & erection of 16 flats

9018309 446-448 Demolition of Unknown Y 0.089 24/09/2009 24/09/2012 4 0 2 0 0 0 0 0 0 0 0 0 4 0 2 0 Full GRANTED Whippendell dwelling, Road, Watford erection of 2 dwellings, conversion of dwelling into 2 flats 9022605 Adj 480 Erection of Unknown Y 0.027 27/04/2005 27/04/2010 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Whippendell dwelling Road, Watford 9023909 357 Whippendell Conversion of Unknown Y 0.026 21/05/2009 21/05/2012 4 0 1 0 0 0 0 0 0 0 0 0 4 0 3 0 Full GRANTED Road, Watford 1 dwelling into 4 dwellings

9032608 Former Demolition of Unknown Y 0.189 11/06/2008 11/06/2011 31/03/2010 31/03/2011 18 0 1 0 18 0 17 0 18 0 18 0 0 0 0 0 Full COMPLET Highwayman P H, public house & ED Tolpits Lane, staff dwelling & Watford erection of 18 flats

9037908 70 Euston Conversion of Unknown Y 0.012 04/09/2008 04/09/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Avenue, Watford 1 dwelling into 2 dwellings

9044008 Fire & Ambulance Demolition of Unknown Y 1.084 26/06/2008 26/06/2010 31/03/2010 90 27 0 0 0 0 0 0 0 0 0 0 90 27 90 27 Full STARTED Station, 562-572 fire & Whippendell ambulance Road, Watford station & erection of 90 dwellings 9055109 474 Whippendell Conversion of Unknown Y 0.028 08/09/2009 08/09/2012 31/03/2010 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Road, Watford 1 dwelling into ED 2 dwellings PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9064409 508-510 cou of ground Unknown Y 0.025 08/10/2009 08/10/2012 3 0 0 0 0 0 0 0 0 0 0 0 3 0 3 0 Full GRANTED Whippendell floor from Road, Watford newsagents to bar & extension to form 3 flats 9078609 192 Hagden Lane, Conversion of Unknown Y 0.015 02/12/2009 02/12/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1st floor flat into 2 flats

9129308 206 Hagden Lane, Conversion of Unknown Y 0.016 27/11/2008 27/11/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford upper floors from 1 flat into 2 flats

Holywell Ward Totals: 1.716 150 27 12 0 20 0 18 0 20 0 19 0 129 27 119 27

---- Ward Name Leggatts Ward

10/00225/COU 93, Gammons Conversion of Change of use of non-res Y 0.000 30/04/2010 30/04/2013 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Lane, Watford, ground floor building to dwelling(s) ED WD24 5HU office into flat

10/00345/FUL Land R/O, 123- Erection of 6 New residential building N 0.219 10/06/2010 10/06/2013 6 0 0 0 0 0 0 0 0 0 0 0 6 0 6 0 Full GRANTED 129, Gammons dwellings Lane, Watford, WD24 5JD 10/00894/FULM Yeatman House, Demolition of New residential building Y 0.314 23/12/2010 23/12/2013 12 12 40 40 0 0 0 0 0 0 0 0 12 12 -28 -28 Full GRANTED Foxhill, Watford, 40 elderly WD24 6SU persons flats & erection of 12 dwellings 10/00965/COU 99, Leggatts Way, Cou from shop Change of use of non-res Y 0.029 02/12/2010 02/12/2013 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Watford, WD24 & garage to 2 building to dwelling(s) 5NQ flats

9005210 Adj 83 Erection of Unknown Y 0.014 18/03/2010 18/03/2013 31/03/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Harebreaks, dwelling Watford 9047908 Adj 30 Chestnut Erection of 2 Unknown Y 0.028 11/06/2008 11/06/2011 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Walk, Watford flats

9056807 R/O 154 Ridge Erection of 11 Unknown Y 0.306 13/02/2008 13/02/2011 31/03/2011 11 0 0 0 0 0 0 0 0 0 0 0 11 0 11 0 Full STARTED Lane +, R/O dwellings 271,273,275 Gammons Lane, Watford 9066807 43 Fuller Road, conversion of 1 Unknown Y 0.026 09/07/2007 09/07/2010 31/03/2009 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Watford dwelling into 2 ED flats 9073009 103 Leggatts Erection of Unknown Y 0.039 10/11/2009 10/11/2012 31/03/2010 31/03/2011 4 0 1 0 4 0 3 0 4 0 4 0 0 0 0 0 Full COMPLET Wood Avenue, extension & ED Watford conversion into 4 flats 9077309 Adj 6 Chestnut Erection of Unknown Y 0.013 30/11/2009 30/11/2012 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Walk, Watford dwelling ED

9086609 North Watford First floor Unknown Y 0.060 25/01/2010 25/01/2013 31/03/2010 31/03/2011 4 0 0 0 4 0 4 0 4 0 4 0 0 0 0 0 Full COMPLET Mosque, 167 extension ED North Western comprising 4 Avenue, Watford flats, library & meeting rooms. 9096109 42 Berry Avenue, Conversion of Unknown Y 0.022 03/02/2010 03/02/2013 31/03/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford 1 dwelling into 2 dwellings

9107407 14 Chestnut Walk, conversion of 1 Unknown Y 0.030 15/11/2007 15/11/2010 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Watford dwelling into 2 flats 9121108 102 Leggatts Demolition of Unknown Y 0.040 05/11/2008 05/11/2011 31/03/2009 4 0 1 0 0 0 -1 0 0 0 0 0 4 0 4 0 Full STARTED Wood Avenue, dwelling & Watford erection of 4 flats 9138708 R/O 263 - 267 Erection of 9 Unknown Y 0.008 16/02/2010 16/02/2013 31/03/2011 9 0 0 0 0 0 0 0 0 0 0 0 9 0 9 0 Full STARTED Gammons Lane, flats Watford Leggatts Ward Totals: 1.148 63 12 45 40 12 0 9 0 12 0 11 0 49 12 8 -28

---- Ward Name Meriden Ward

10/00130/FUL 798, St Albans Conversion of Change of use of non-res Y 0.000 07/04/2010 07/04/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, 1st floor from building to dwelling(s) WD25 9FF D1 to flat

10/00363/FUL 14, Harvest End, Erection of New residential building N 0.058 17/08/2010 17/08/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Watford, WD25 dwelling 9UB 10/01167/FUL Land adj, 26, Erection of New residential building N 0.030 18/01/2011 18/01/2014 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Coates Way, dwelling Watford, WD25 9NS 10/01275/OUT 14, Harvest End, Erection of New residential building N 0.041 10/03/2011 10/03/2014 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Outline GRANTED Watford, WD25 dwelling 9UB 9007808 Adj 130 Fourth Erection of Unknown Y 0.020 13/03/2008 13/03/2011 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Avenue, Watford dwelling

9023008 990-996 & R/O Demolition of 4 Unknown Y 0.222 26/06/2008 26/06/2011 9 0 4 0 0 0 0 0 0 0 0 0 9 0 5 0 Full GRANTED 988 St Albans dwelling & Road, Watford erection of 9 dwellings PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9057609 Garage Land R/O Erection of 6 Unknown Y 0.283 14/09/2009 14/09/2012 31/03/2010 31/03/2011 6 6 0 0 6 6 6 6 6 6 6 6 0 0 0 0 Full COMPLET Pinetree House, dwellings ED The Turnstones, Watford

9109408 R/O 722-724 St Erection of 3 Unknown Y 0.105 23/10/2008 23/10/2010 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Albans Road, dwellings Watford 9118308 Former Meriden Demolition of Unknown Y 0.178 20/11/2008 20/11/2011 31/03/2009 22 0 0 0 0 0 0 0 0 0 0 0 22 0 22 0 Full STARTED Nursery School, nusery school Watford & erection of 22 flats

9120408 Adj 107 The Demolition of Unknown Y 0.021 03/11/2008 03/11/2011 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Phillipers, Watford domestic ED garage & erection of dwelling 9127408 22 Eastlea Conversion of Unknown Y 0.022 24/11/2008 24/11/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Avenue, Watford 1 dwelling into 2 dwellings

9135807 756 758 & 758a demolition of 3 Unknown Y 0.167 22/07/2008 22/07/2011 14 0 3 0 0 0 0 0 0 0 0 0 14 0 11 0 Outline GRANTED St Albans Road, dwellings & Watford erection of 14 flats 9149308 Former Sun Demolition of Unknown Y 0.430 02/03/2009 02/03/2012 31/03/2010 59 18 0 0 0 0 0 0 0 0 0 0 59 18 59 18 Full STARTED Chemical Site industrial & (part), Cow Lane, erection of 59 Watford dwellings. 9160207 Former Sun Demolition of New residential building Y 1.701 21/02/2008 21/02/2010 31/03/2009 223 87 0 0 158 87 158 87 121 61 121 61 65 0 65 0 Full STARTED Chemicals (part), industrial & Cow Lane, erection of 223 Watford dwellings,

Meriden Ward Totals: 3.278 344 111 8 0 165 93 165 93 128 67 128 67 175 18 167 18

---- Ward Name Nascot Ward

10/00010/FUL 117c, St Albans Erection of flat Extension to building for Y 0.000 28/07/2010 28/07/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, at 1st floor residential unit(s) WD17 1RD 10/00108/FUL 8, Nascot Wood Demolition of New residential building Y 0.000 14/10/2010 14/10/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford, bungalow & WD17 4RS erection of 2 houses 10/00162/FUL 1, Minerva Drive, Conversion of Conversion of existing Y 0.000 16/04/2010 16/04/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED watford, WD24 dwelling into 2 dwelling(s) 5LD flats 10/00293/FUL The Beaver PH, Demolition of New residential building Y 0.000 24/05/2010 24/05/2013 31/03/2011 31/03/2011 6 0 1 0 6 0 5 0 6 0 5 0 0 0 0 0 Full COMPLET 98 Courtlands PH & erection ED Road, Watford, of 6 dwellings WD17 4JA 10/00343/FUL 133, St Albans Cou from Change of use of non-res Y 0.000 04/06/2010 04/06/2013 4 0 0 0 0 0 0 0 0 0 0 0 3 0 3 0 Full GRANTED Road, Watford, offices to 4 building to dwelling(s) WD17 1RA flats 10/00356/FUL Land R/O, 12, Erection of New residential building N 0.091 08/06/2010 08/06/2013 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Hampden Way, dwelling DED Watford, WD17 4SS 10/00510/COU Huskards, 49 Cou from Change of use of non-res Y 0.000 22/07/2010 22/07/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Stratford Road, nursing home building to dwelling(s) Watford, WD17 to HMO & self 4NY contained flat

10/00602/FUL Land R/O, 12, Erection of New residential building N 0.091 17/08/2010 17/08/2013 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Hampden Way, dwelling DED Watford, WD17 4SS 10/00696/FUL 147, St Albans Erection of 8 New residential building Y 0.000 15/09/2010 15/09/2013 8 0 2 0 0 0 0 0 0 0 0 0 8 0 6 0 Full GRANTED Road, watford, dwellings & WD17 1RA commercial floorspace 10/00803/FUL Land R/O, 12, Erection of New residential building N 0.091 20/10/2010 20/10/2013 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Hampden way, dwelling DED Watford, WD17 4SS 10/00890/FUL Adj, 141, Ridge Erection of New residential building N 0.000 24/11/2010 24/11/2013 31/03/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Lane, Watford, dwelling WD17 4SU 10/00998/FUL 52-54, Church Extension & Conversion of existing Y 0.050 08/11/2010 08/11/2013 2 0 4 0 0 0 0 0 0 0 0 0 2 0 -2 0 Full GRANTED Road, Watford, conversion of 4 dwelling(s) WD17 4PU flats back into 2 dwellings

10/01156/FUL 133, St Albans Cou of 2nd Change of use of non-res Y 0.004 05/01/2011 05/01/2014 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Road, Watford, floor & building to dwelling(s) WD17 1RA loftspace into 2 flats 10/01206/FUL R/O 4-6, Essex Erection of 6 New residential building N 0.057 28/01/2011 28/01/2014 6 0 0 0 0 0 0 0 0 0 0 0 6 0 6 0 Full GRANTED Road, Watford, flats WD17 4EP 10/01272/REM Land at & R/O, 53 - Erection of 5 New residential building N 0.342 10/03/2011 10/03/2014 5 0 0 0 0 0 0 0 0 0 0 0 5 0 5 0 Reserved GRANTED 61 Nascot Wood dwellings Matters Road, & R/O 12 Ridge Road, Watford, WD17 4SJ 11/00012/FUL Land R/O, 12, Erection of New residential building N 0.058 14/03/2011 14/03/2014 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Hampden Way, dwelling Watford, WD17 4SS PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

11/00115/EXT 30, Langley Road, Cou from HMO Change of use of non-res Y 0.000 18/03/2011 18/03/2014 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Watford, WD17 to 4 flats building to dwelling(s) 4PT 9003010 Adj 141 Ridge Erection of Unknown Y 0.038 10/03/2010 10/03/2013 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Lane, Watford dwelling DED

9012708 Prince Michael Of cou from 6 Unknown Y 0.111 20/03/2008 20/03/2011 31/03/2009 31/03/2011 0 0 6 0 0 0 -6 0 0 0 -6 0 0 0 0 0 Full COMPLET Kent Court, sheltered flats ED Stratford Road, to part nursing Watford home 9018008 30 Langley Road, conversion of Unknown Y 0.025 26/03/2008 26/03/2011 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford HMO into 4 DED flats 9025208 5 Rosecroft Drive, Demolition of Unknown Y 0.111 13/06/2008 13/06/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Outline GRANTED Watford 1dwelling & erection of 2 dwellings 9032409 33a Church Road, Conversion of Unknown Y 0.016 26/06/2009 26/06/2012 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Watford ground floor ED workshop/store into live/work unit

9045407 R/O 24 Denewood Erection of 2 Unknown Y 0.157 02/05/2008 02/05/2011 31/03/2011 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full STARTED Close, Watford dwellings

9061508 Adj 10 Nascot Erection of 2 Unknown Y 0.086 09/07/2008 09/07/2011 31/03/2010 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full STARTED Wood Road/, dwellings Watford 9065309 Watford School Of COU from Change of use of non-res Y 0.221 13/11/2009 13/11/2012 31/03/2010 24 0 0 0 0 0 0 0 0 0 0 0 24 0 24 0 Full STARTED Music, Nascot music school building to dwelling(s) Wood Road, to 8 flats, Watford, WD17 demolition of 4RS coach house & erection of 2 dwellings & erection of 14 flats 9088607 135 St Albans conversion of Unknown Y 0.022 15/11/2007 15/11/2010 31/03/2010 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full STARTED Road, Watford shop & flat into shop & 3 flats

9092308 48, 48a & 50 The Demolition of 6 Unknown Y 0.364 20/01/2009 20/01/2012 53 0 6 0 0 0 0 0 0 0 0 0 53 0 47 0 Full GRANTED Avenue, Strathay dwellings & & 2 Alexandra erection of 52 Road, Watford sheltered flats & managers flat 9093008 Adj 88 Langley Erection of Unknown Y 0.040 18/12/2008 18/12/2011 31/03/2010 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Road, Watford dwelling ED

9101608 Land At 53 & R/O Part demolition Unknown Y 0.342 23/02/2009 23/02/2012 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Outline SUPERSE 53-61 Nascot of 53 Nascot DED Wood Road, & Wood Road, R/O 12 Ridge demolition of Lane, Watford garage & erection of 5 dwellings

9137808 Cassio College, Redevelopmen Unknown Y 4.779 09/03/2009 09/03/2014 31/03/2011 223 67 0 0 0 0 0 0 0 0 0 0 223 67 223 67 Full STARTED Langley Road, t comprising Watford 223 dwellings, retail units & doctors' surgery

9139908 R/O 51-53 Malden Erection of Unknown Y 0.021 02/06/2009 02/06/2012 31/03/2010 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Road, Watford dwelling

9164806 Willow Grange, cou from New residential building Y 1.960 21/03/2007 21/03/2010 31/03/2008 31/03/2011 174 72 0 0 174 72 174 72 106 26 106 26 0 0 0 0 Full COMPLET Church Road, offices to 78 ED Watford flats and erection of additional 96 dwellings Nascot Ward Totals: 9.077 544 139 23 0 182 72 175 72 114 26 107 26 348 67 332 67

---- Ward Name Oxhey Ward

10/00451/COU 73, Chalk Hill, Cou of ground Change of use of non-res Y 0.000 05/07/2010 05/07/2013 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Watford, WD19 floor shop to building to dwelling(s) ED 4DA flat 10/00592/FUL 57, Eastbury Replacement New residential building Y 0.070 16/08/2010 16/08/2013 31/03/2011 1 0 1 0 0 0 -1 0 0 0 -1 0 1 0 1 0 Full STARTED Road, Watford, dwelling WD19 4JN 10/00841/FUL 13 & 15, Green Demolition of New residential building Y 0.000 18/10/2010 18/10/2013 31/03/2011 6 0 1 0 0 0 -1 0 0 0 -1 0 6 0 6 0 Full STARTED Lane, Watford, no 15 & WD19 4NL erection of 6 dwellings 10/00861/FUL 18, Capel Road, Demolition of Conversion of existing Y 0.022 14/02/2011 14/02/2014 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford, WD19 workshop, dwelling(s) 4AE erection of extension & conversion to 2 dwellings 10/01022/FUL 59, Eastbury Replacement New residential building Y 0.070 23/11/2010 23/11/2013 1 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 Full GRANTED Road, Watford, dwelling WD19 4JN 10/01279/FUL Land R/O, 20-22, Erection of New residential building N 0.033 08/02/2011 08/02/2014 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Capel Road, dwelling Watford 11/00050/FUL Land R/O, 16, Erection of 2 New residential building N 0.102 07/03/2011 07/03/2014 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Green Lane, dwellings Watford, WD19 4NJ PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9002509 25 Chalk Hill, Cou of ground Unknown Y 0.018 07/07/2009 07/07/2012 31/03/2010 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Watford floor to flat ED

9005907 Contract House, Demolition of Unknown Y 0.134 31/01/2008 31/01/2011 31/03/2011 3 0 0 0 0 0 0 0 0 0 0 0 3 0 3 0 Full STARTED 19a Watford builders yard & Heath, Watford erection of 3 dwellings 9011109 5 Field Road, Replacement Unknown Y 0.020 08/04/2009 08/04/2012 31/03/2011 31/03/2011 1 0 1 0 1 0 0 0 1 0 0 0 0 0 0 0 Full COMPLET Watford dwelling ED

9014009 24 Green Lane, Demolition of Unknown Y 0.241 14/05/2009 14/05/2012 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Outline GRANTED Watford dwelling and erection of 3 dwellings 9033509 13 & 15 Green Demolition of 1 Unknown Y 0.493 02/07/2009 02/07/2012 6 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Lane, Watford dwelling & DED erection 6 dwellings 9044509 Former J R redevelopment Unknown Y 0.402 07/09/2009 07/09/2014 31/03/2011 71 24 4 0 0 0 -2 0 0 0 0 0 71 24 69 24 Full STARTED Tagger, Pinner for 71 flats, Road/Aldenham shops & B1 Road, Watford use 9052609 73 Chalk Hill, Cou of ground Unknown Y 0.020 08/09/2009 08/09/2012 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford floor from shop DED to flat

9056508 2 Green Lane, Erection of New residential building Y 0.104 05/06/2008 05/06/2011 31/03/2011 1 0 1 0 0 0 -1 0 0 0 0 0 1 0 1 0 Full STARTED Watford replacement dwelling 9090509 Blackwell House, Erection of 50 Unknown Y 0.769 01/03/2010 01/03/2013 50 15 0 0 0 0 0 0 0 0 0 0 50 15 50 15 Outline GRANTED Watford flats

9141008 Between 38-40 Demolition of Unknown Y 0.018 16/12/2008 16/12/2011 31/03/2010 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Upper Paddock disused ED Road, Watford workshop & erection of dwelling 9143808 R/O 57-59 Upper demolition of Unknown Y 0.067 29/01/2009 29/01/2011 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full GRANTED Paddock Road, garages & Watford erection of dwelling Oxhey Ward Totals: 2.583 153 39 12 0 4 0 -2 0 4 0 1 0 141 39 136 39

---- Ward Name Park Ward

10/00301/FUL Adj 212, Erection of 4 New residential building Y 0.000 24/05/2010 24/05/2013 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Harwoods Road, flats Watford, WD18 7RX 10/00417/FUL The Small House, Erection of New residential building Y 0.000 16/07/2010 16/07/2013 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE & R/O Capel dwelling DED House, Plot A, Temple Close, Watford, WD17 3DR 10/00630/FUL 92, Gade Avenue, Demolition of New residential building Y 0.000 12/08/2010 12/08/2013 3 0 1 0 0 0 0 0 0 0 0 0 3 0 2 0 Full GRANTED Watford, WD18 bungalow & 7LJ erection of 3 bungalows 10/00855/FUL 16, Roughwood Demolition of New residential building Y 0.406 07/12/2010 07/12/2013 4 0 1 0 0 0 0 0 0 0 0 0 4 0 3 0 Full GRANTED Close, Watford, dwelling & WD17 3HN erection of 4 dwellings 10/00885/FUL The Small House, Erection of New residential building Y 0.000 28/10/2010 28/10/2010 31/03/2011 1 0 1 0 0 0 -1 0 0 0 -1 0 1 0 1 0 Full STARTED Temple Close, dwelling Watford, WD17 3DR 9003910 R/O 123 erection of 2 Unknown Y 0.144 11/03/2010 11/03/2013 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Cassiobury Drive, dwellings Access Cottage Close, Watford

9029209 92 Gade Avenue, Replacement Unknown Y 0.188 11/06/2009 11/06/2012 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Watford dwelling DED

9040609 4 Cassiobury Conversion of Unknown Y 0.033 21/07/2009 21/07/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Drive, Watford dwelling into 2 dwellings

9043009 R/O 40 The Erection of Unknown Y 0.040 02/10/2009 02/10/2012 1 0 1 0 0 0 -1 0 0 0 0 0 1 0 1 0 Full GRANTED Gardens, Watford dwelling

9052608 173 Hempstead Demolition of Unknown Y 0.068 30/05/2008 30/05/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford offices & erection of dwelling 9056304 61 The Avenue, Erection of Unknown Y 0.092 24/08/2004 24/08/2009 31/03/2010 1 0 1 0 0 0 -1 0 0 0 0 0 1 0 1 0 Full STARTED Watford replacement dwelling 9069407 R/O 44-46 Erection of Unknown Y 0.105 09/08/2007 09/07/2010 1 0 1 0 0 0 -1 0 0 0 0 0 0 0 0 0 Full LAPSED Rickmansworth dwelling Road, Watford (completed in error 2007) 9083408 53 Cassiobridge Conversion of Unknown Y 0.018 27/08/2008 27/08/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford 1 dwelling into 2 dwellings

9091709 79 Hempstead demolition of Unknown Y 0.089 05/01/2010 05/01/2013 31/03/2010 31/03/2011 2 0 1 0 2 0 1 0 2 0 2 0 0 0 0 0 Full COMPLET Road, Watford dwelling & ED erection of 2 dwellings 9095609 Adj 212 Harwoods Erection of 4 Unknown Y 0.049 02/02/2010 02/02/2013 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Road, Watford flats DED PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9114308 60 Mildred Conversion of Unknown Y 0.034 21/11/2008 21/11/2011 4 0 1 0 0 0 0 0 0 0 0 0 4 0 3 0 Full GRANTED Avenue, Watford dwelling into 4 flats 9118904 25-31 King demolition of New residential building Y 0.380 15/03/2005 15/03/2010 31/03/2007 14 0 0 0 10 0 10 0 0 0 0 0 4 0 4 0 Full STARTED Georges Avenue, workshop & Watford erection of 14 dwellings 9163507 Land At Capel Demolition of Unknown Y 0.213 15/08/2008 15/08/2011 2 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED House & The dwelling & Small House, erection of 2 Temple Close, dwellings Watford Park Ward Totals: 1.859 50 0 11 0 12 0 7 0 2 0 1 0 30 0 25 0

---- Ward Name Stanborough Ward

10/00599/FUL 8, Bramble Close, Extension & Conversion of existing Y 0.050 02/09/2010 02/09/2013 31/03/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford, WD25 conversion to 2 dwelling(s) 0HF flats 10/00835/FUL 863, St Albans Conversion of Conversion with Extension Y 0.074 07/01/2011 07/01/2013 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford, 3 garages into WD25 0NH 1 flat 10/01249/FUL Adj 47, Ross Erection of 2 New residential building N 0.022 10/02/2011 10/02/2014 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Crescent, masionettes Watford, WD25 0DA 9019907 563 St Albans conversion of 1 Unknown Y 0.029 19/04/2007 19/04/2010 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Road, Watford dwelling into 2 ED flats 9031708 R/O 4-12 Demolition of Unknown Y 0.122 05/06/2008 05/06/2011 5 0 0 0 0 0 0 0 0 0 0 0 5 0 5 0 Full GRANTED Purbrock Avenue, garages & Watford erection of 5 dwellings 9035909 R/O 11 - 17 Erection of 5 Unknown Y 0.165 03/07/2009 03/07/2012 31/03/2010 31/03/2011 5 0 0 0 5 0 5 0 5 0 5 0 0 0 0 0 Full COMPLET Garston Drive, dwellings ED Watford 9038908 Adj 47 Ross Erection of Unknown Y 0.022 07/05/2008 07/05/2011 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Crescent, Watford dwelling DED

9053808 Adj 122 Briar Erection of Unknown Y 0.013 08/07/2008 08/07/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford dwelling

9076907 13 Hemming conversion of 1 Unknown Y 0.033 29/10/2007 29/10/2010 31/03/2008 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Way, Watford dwelling into 2 ED flats 9076909 R/O 103 North Erection of Unknown Y 0.022 30/11/2009 30/11/2012 31/03/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Approach, dwelling Watford 9082108 Dome Service Erection of Unknown Y 0.126 18/03/2009 18/03/2012 6 0 0 0 0 0 0 0 0 0 0 0 6 0 6 0 Full GRANTED Station, Watford retail shops & 6 apartments 9084207 2 & 2a Briar Road, conversion of 2 Unknown Y 0.052 15/08/2007 15/08/2010 2 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Watford flats into 1 dwelling & erection of 1 dwelling 9109908 Land R/O, Erection of Unknown Y 0.023 21/11/2008 21/11/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Outline GRANTED Watford dwelling

9113608 765 St Albans Demolition of Unknown Y 0.149 09/12/2008 09/12/2011 16 0 0 0 0 0 0 0 0 0 0 0 16 0 16 0 Full GRANTED Road, Watford car showroom & offices & erection of 16 flats

Stanborough Ward Totals: 0.902 47 0 5 0 9 0 7 0 9 0 7 0 35 0 34 0

---- Ward Name Tudor Ward

09/00268/FUL 7, Bushey Mill Conversion of Conversion of existing Y 0.000 13/05/2010 13/05/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Lane, Watford, dwelling into 2 dwelling(s) WD24 7QT flats 10/00347/FUL 1st floor, 462-464, Cou from Change of use of non-res Y 0.022 25/05/2010 25/05/2013 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED St Albans Road, offices to 4 building to dwelling(s) Watford flats 10/00809/FUL 71, Balmoral Conversion of Conversion of existing Y 0.030 25/11/2010 25/11/2013 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Road, Watford, dwelling into 2 dwelling(s) ED WD24 4ES dwellings

10/00810/FUL 39, Munden Conversion of Conversion of existing Y 0.031 07/10/2010 07/10/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Grove, Watford, dwelling into 2 dwelling(s) WD24 7EF flats 9021508 462 St Albans Cou of 1st floor Unknown Y 0.022 28/04/2008 28/04/2011 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full GRANTED Road, Watford from offices to 2 flats and creation of 2 flats in roof space

9105306 1 & 2 Simmons cou from 2 Unknown Y 0.031 06/10/2006 06/10/2009 31/03/2008 0 0 2 0 0 0 -1 0 0 0 0 0 0 0 -1 0 Full STARTED Cottages, Watford dwellings to offices 9155508 R/O 177 Bushey Erection of Unknown Y 0.018 03/07/2009 03/07/2012 31/03/2010 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Mill Lane, Watford dwelling ED

Tudor Ward Totals: 0.154 15 0 5 0 3 0 1 0 3 0 2 0 12 0 9 0

---- Ward Name Vicarage Ward PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

09/00946/FUL 2a, Whippendell Conversion of Conversion of existing Y 0.000 29/04/2010 29/04/2013 31/03/2011 31/03/2011 3 0 1 0 3 0 2 0 3 0 2 0 0 0 0 0 Full COMPLET Road, watford, upper floors dwelling(s) ED WD18 7LU into 3 flats

10/00165/FUL 199, Vicarage Conversion of Conversion of existing Y 0.000 14/06/2010 14/06/2013 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Road, Watford, HMO into 2 dwelling(s) WD18 0HA flats 10/00185/FUL 2, Whippendell Extension & Change of use of non-res Y 0.022 04/05/2010 04/05/2013 31/03/2011 4 0 0 0 0 0 0 0 0 0 0 0 4 0 4 0 Full STARTED Road, Watford, conversion of building to dwelling(s) WD18 7LU ground floor from dental surgery to 4 flats 10/00212/FUL 57, Holywell Conversion of Conversion of existing Y 0.000 20/05/2010 20/05/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford, dwelling into 2 dwelling(s) WD18 0HT flats 10/00467/EXT 14, Kensington Renewal of Conversion of existing Y 0.013 25/06/2010 25/06/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Avenue, Watford, planning dwelling(s) WD18 7RY permission 05/00278/FUL for the conversion of dwelling into 2 flats 10/00509/LDC 133, Vicarage Certificate of Conversion of existing Y 0.017 29/09/2010 29/09/2010 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Certificate COMPLET Road, Watford, lawfulness for dwelling(s) of Lawful ED WD18 0HA use of building Use as 2 flats

10/00804/FUL 24, Vicarage Cou of 1st floor New residential building Y 0.011 01/11/2010 01/11/2013 1 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 Full GRANTED Road, Watford, from flat to WD18 0ED HMO. Erection of flat

10/01238/FUL 201, Whippendell Conversion of Conversion of existing Y 0.015 10/02/2011 10/02/2014 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford, dwelling into 2 dwelling(s) WD18 7NN flats

9002207 Watford Football erection of 164 Unknown Y 0.425 03/04/2007 03/04/2010 31/03/2008 31/03/2011 164 164 0 0 164 164 164 164 164 164 164 164 0 0 0 0 Full COMPLET Club, Vicarage flats ED Road, Watford 9005809 240 Whippendell Conversion of Unknown Y 0.014 20/04/2009 20/04/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford 1 dwelling into 2 flats 9006310 18 Wiggenhall conversion of 1 Unknown Y 0.019 24/03/2010 24/03/2013 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford dwelling into 2 flats 9020409 42 Holywell Road, Conversion of Unknown Y 0.013 20/05/2009 02/05/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1 dwelling into 2 dwellings

9027805 14 Kensington Conversion of Conversion of existing Y 0.013 03/06/2005 03/06/2010 31/03/2006 31/03/2011 3 0 3 0 3 0 0 0 1 0 -1 0 0 0 0 0 Full COMPLET Avenue, Watford 1 dwelling into dwelling(s) ED 2 flats 9031508 1a &1b Brightwell Conversion of Unknown Y 0.016 21/10/2008 21/10/2011 4 0 1 0 0 0 0 0 0 0 0 0 4 0 3 0 Full GRANTED Road, Watford 1 dwelling into 4 flats 9033909 24 Princes Street, Conversion of Unknown Y 0.014 01/07/2009 01/07/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford HMO to 2 flats

9035905 2 Cardiff Road, Conversion of Unknown Y 0.016 13/06/2005 13/06/2010 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Watford 1 dwelling into ED 2 flats 9046408 3 Willow Lane, Conversion of Unknown Y 0.025 23/05/2008 23/05/2011 31/03/2009 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford 1 dwelling into 2 dwellings

9051709 32 Pretoria Road, Conversion of Unknown Y 0.011 12/08/2009 12/08/2012 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1 dwelling into 2 dwellings

9065007 33 Cardiff Road, Cou of ground Unknown Y 0.008 26/07/2007 26/07/2010 31/03/2007 2 0 1 0 1 0 0 0 0 0 0 0 1 0 1 0 Full STARTED Watford floor from shop to flat (completed in error 2007)

9066509 62b Harwoods cou from light Unknown Y 0.014 02/11/2009 02/11/2012 2 0 0 0 0 0 0 0 0 0 0 0 2 0 2 0 Full GRANTED Road, Watford industrial to 2 dwellings 9075209 48 Liverpool Conversion of Unknown Y 0.015 24/11/2009 24/11/2012 31/03/2010 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Road, Watford 1 dwelling into 2 dwellings

9086108 36 Harwoods Conversion of Unknown Y 0.012 04/09/2008 04/09/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford 1 dwelling into 2 dwellings

9094109 72 Vicarage Road, Conversion of Unknown Y 0.016 10/02/2010 10/02/2013 31/03/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Watford 1 dwelling into 2 dwellings

9110408 16 Chester Road, Conversion of Unknown Y 0.015 10/10/2008 10/10/2011 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Watford 1 dwelling into ED 2 dwellings

9111307 49 Kensington conversion of 1 Unknown Y 0.014 11/10/2007 11/10/2010 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Avenue, Watford dwelling into 2 flats 9121008 140 Harwoods conversion of Unknown Y 0.006 13/11/2008 13/11/2011 31/03/2010 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full STARTED Road, Watford 1flat into 2 flats PP Ref Address Description Dev Types PDL Gross Area Granted Lapses Started Completed Prop Prop Aff Units Lost Lost Aff Gross Gross Net Net Gross Gross Net Net Gross Gross Net Net Applicati Current Units Comps Comps Comps Comps Comps Comps Comps Comps Comm Comm Aff Comm Comm Aff on Type Status Aff Aff FY Aff FY FY Aff in FY

9122708 6-10 Whippendell Demolition of 3 Unknown Y 0.116 10/12/2008 10/12/2011 13 0 3 0 0 0 -3 0 0 0 -3 0 13 0 13 0 Full GRANTED Road, Watford dwellings & erection of 4 houses & 9 flats 9124908 R/O 13 Harwoods Demolition of Unknown Y 0.008 09/12/2008 09/12/2011 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 Full GRANTED Road, Watford outbuildings & erection of dwelling 9129508 30 Holywell Road, Conversion of Unknown Y 0.014 12/12/2008 12/12/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1 dwelling into 2 dwellings

9130308 257 Whippendell Conversion of Unknown Y 0.014 03/12/2008 03/12/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Road, Watford HMO into 2 flats 9130808 36 Chester Road, Conversion of Unknown Y 0.015 18/12/2008 18/12/2011 2 0 1 0 0 0 0 0 0 0 0 0 2 0 1 0 Full GRANTED Watford 1 dwelling into 2 dwellings

9134208 2 Whippendell Conversion of Unknown Y 0.023 14/01/2009 14/01/2012 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Road, Watford upper floors DED from 1 flat into 2 flats

9137208 167 Chester Conversion of Unknown Y 0.012 16/01/2009 16/01/2012 31/03/2011 31/03/2011 2 0 1 0 2 0 1 0 2 0 1 0 0 0 0 0 Full COMPLET Road, Watford 1 dwelling into ED 2 dwellings

9138508 47/49 Durban Conversion of Unknown Y 0.025 18/12/2008 18/12/2011 4 0 2 0 0 0 0 0 0 0 0 0 4 0 2 0 Full GRANTED Road East, 2 houses into 4 Watford flats 9139708 182 Whippendell Extension & Unknown Y 0.036 19/12/2008 19/12/2011 5 0 1 0 0 0 0 0 0 0 0 0 5 0 4 0 Full GRANTED Road, Watford conversion of dwelling into 5 flats Vicarage Ward Totals: 1.007 252 164 35 0 179 164 167 164 176 164 166 164 69 0 48 0

---- Ward Name Woodside Ward

10/00061/EXT Adj, 57, Louvian Renewal of New residential building N 0.000 12/04/2010 12/04/2013 31/03/2011 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Way, Watford, 06/01271/FUL ED WD25 7EP for erection of dwelling 10/00563/FUL 69-71, High Road, Demolition of 2 New residential building Y 0.182 01/09/2010 01/09/2013 31/03/2011 8 0 2 0 0 0 -2 0 0 0 -2 0 8 0 8 0 Full STARTED Watford, WD25 bungalows & 7AL erection of 8 dwellings 9024707 73 High Road, demolition of 1 Unknown Y 0.157 19/07/2007 19/07/2010 9 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 Full LAPSED Watford dwellings & erection of 2 dwellings 9053608 69-71 High Road, demolition of 2 Unknown Y 0.178 26/06/2008 26/06/2011 7 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Leavesden, dwellings & DED Watford erection of 7 dwellings 9068709 Land Adj erection of 15 Unknown N 0.264 05/11/2009 05/11/2012 15 0 0 0 0 0 0 0 0 0 0 0 15 0 15 0 Full GRANTED Woodside Leisure flats Park, Watford

9103008 141 Horseshoe Conversion to Unknown Y 0.062 22/09/2008 22/09/2011 1 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 Full GRANTED Lane, Watford HMO

9127106 Adj 57 Louvian Erection of Unknown Y 0.022 25/04/2007 25/04/2010 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Full SUPERSE Way, Watford dwelling DED

9127308 Alban Wood Demolition of New residential building Y 0.589 20/11/2008 20/11/2010 31/03/2009 31/03/2011 29 9 0 0 29 9 29 9 22 9 22 9 0 0 0 0 Full COMPLET Junior School, school ED Newhouse buildings & Crescent, Watford erection of 29 dwellings 9132108 R/O 201 Erection of Unknown Y 0.054 18/12/2008 18/12/2011 31/03/2009 31/03/2011 1 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 Full COMPLET Horseshoe Lane, dwelling ED Watford Woodside Ward Totals: 1.508 72 9 6 0 31 9 29 9 24 9 22 9 24 0 23 0

Not on a Site Totals: 28.306 2542 695 213 40 790 378 744 378 665 306 635 306 1526 300 1386 260

Watford Totals: 55.413 3291 937 216 40 790 378 742 378 665 306 633 306 2275 542 2134 502

Report Total: 55.413 3291 937 216 40 790 378 742 378 665 306 633 306 2275 542 2134 502

Technical Note 2: Future Year Model Development

APPENDIX

B

HEALTH CAMPUS / WIGGENHALL ROAD JUNCTION LAYOUT

Appendix B

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Technical Note 2: Future Year Model Development

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 224042/01

ISSUE HISTORY

Issue No. Date Details

1 22 Sep 11 Draft 2 02 Nov 11 Revised Draft

3 23 Dec 11 Final 4 1 Feb 12 Revised Final

REVIEW

Originator Steve Oliver

Other Contributors Paul Robinson

Review by: Print Steve Oliver

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

L:\Projects\224\0\42\01\Outputs\Working Notes\Technical Note 2\Tech Note 2 v4 - 03Feb12.docx

Control Sheet Three Rivers and Watford LDF

Technical Note 3: 2026 LDF Sites Technical note

December 2011

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall West Riding House Pegs Lane 67 Albion Street Hertford Leeds LS1 5AA SG13 8DN +44 (0)113 389 6400 www.steerdaviesgleave.com

Technical Note 3: 2026 LDF Sites

CONTENTS

1 TASK 3: IMPACT OF POTENTIAL LDF SITES BY 2026 ...... 1 Introduction ...... 1 Recap ...... 1 Base + Committed + Growth ...... 5 Base + Committed + Potential + Growth (LDF Scenario) ...... 13 Cause of Problems ...... 27 Strategic Highway Routes ...... 29 Public Transport Supply ...... 30 Potential solutions ...... 32 Conclusions ...... 33

FIGURES

Figure 1.1 Volume/Capacity – AM Peak – Base + Committed Scenario ...... 3 Figure 1.2 Volume/Capacity – PM peak – Base + Committed Scenario ...... 4 Figure 1.3 Volume/Capacity – AM Peak – Base + Committed + Growth Scenario ...... 7 Figure 1.4 Volume/Capacity – PM Peak – Base + Committed + Growth Scenario ...... 8 Figure 1.5 Difference Plot – AM peak Demand Flows – Impact of Growth to 2026 ...... 9 Figure 1.6 Difference Plot – PM peak Demand Flows – Impact of Growth to 2026 ...... 10 Figure 1.7 Difference Plot –AM Peak Delay – IMpact of Growth to 2026 ...... 11 Figure 1.8 Difference PLot – PM peak Delay – Impact of Growth to 2026 ...... 12 Figure 1.9 Volume/Capacity – AM Peak – Base + Committed + Potential + Growth Scenario ...... 14 Figure 1.10 Volume/Capacity – PM Peak – Base + Committed + Potential + Growth Scenario ...... 15 Figure 1.11 Difference Plot – AM Peak Demand – Impact of Growth Focussed in Potential Allocation Sites ...... 16 Figure 1.12 Difference Plot – PM Peak Demand – Impact of Growth Focussed in Potential Allocation Sites ...... 17 Figure 1.13 Difference PLot – AM peak Delay - Impact of Growth Focussed in Potential Allocation Sites ...... 18

Contents Technical Note 3: 2026 LDF Sites

Figure 1.14 Difference PLot – PM peak Delay - Impact of Growth Focussed in Potential Allocation Sites ...... 19 Figure 1.15 Delay (seconds) – AM Peak – LDF Scenario ...... 20 Figure 1.16 Delay (seconds) – PM Peak – LDF Scenario ...... 21 Figure 1.17 Difference Plot – AM Peak Demand – Impact of LDF Scenario ...... 25 Figure 1.18 Difference Plot – PM Peak Demand – Impact of LDF Scenario ...... 26 Figure 1.19 Committed Development Trips (User Class 2) – AM peak...... 27 Figure 1.20 LDF Development Trips (User Class 3) – AM peak ...... 28 Figure 1.21 LDF Development Trips (User Class 3) – PM Peak ...... 29

TABLES

Table 1.1 Future Year Matrix Totals ...... 1 Table 1.2 Strategic Network – Motorway Links – Demand Flow ...... 29 Table 1.3 Strategic Network – Motorway Junctions – Demand Flow ...... 29 Table 1.4 Existing Bus Route SUmmary – Key Radials ...... 31 Table 1.5 Potential Future Year Mitigation Summary ...... 34

Contents Technical Note 3: 2026 LDF Sites

1 Task 3: Impact of Potential LDF Sites by 2026

Introduction

1.1 Technical Note 2 provided a detailed summary of the development of 2026 future year demand matrices for use in the Three Rivers and Watford SATURN model, and the derivation of future year networks changes required to help accommodate committed development.

1.2 This third Technical Note looks specifically at growth to 2026, constrained by Tempro, under two scenarios:

I Base + Committed Development + Background Growth to 2026 I Base + Committed and Potential Developments + Background Growth to 2026 1.3 First a comparison is made of the ‘Base+Committed+Growth’ assignment against the ‘Base+Committed’ only results, to help illustrate those areas affected by additional demand growth beyond those sites where committed development has been identified.

1.4 Second, we compare differences in 2026 model performance when a proportion of the future growth is allocated to directly to sites which have been identified as potential sites for further development through both Three Rivers’ and Watford’s ongoing LDF process.

Recap

1.5 To recap, the following table provides a summary of matrices used under each model scenario. User Class 1 (UC1) represents existing trips, plus growth where applicable, with UC2 and UC3 representing trips associated with committed developments and potential LDF development sites respectively.

TABLE 1.1 FUTURE YEAR MATRIX TOTALS

Matrix Scenario 2026 Total

UC1 UC2 UC3

AM: Base + Committed 50925 3104 - 54029

AM: Base + Committed + Growth 55050 3104 - 58154

AM: Base + Committed + Potential + Growth 52300 3104 2742 58146

PM: Base + Committed 54829 3150 - 57979

PM: Base + Committed + Growth 59600 3150 - 62749

PM: Base + Committed + Potential + Growth 56145 3150 3428 62723

1.6 Growth from 2010 to 2026 has been estimated as 1.142 for the AM peak, and 1.144 for the PM peak. This equates to less than 1% per annum. Applying these

1 Technical Note 3: 2026 LDF Sites

factors to the base 2010 matrices gives 2026 matrix total of 58157 in the AM peak and 62725 in the PM peak.

1.7 In each scenario, committed developments (UC2) account for 3104 and 3150 of the growth in the AM and PM peaks respectively. The difference in modelling terms between the two scenarios is that ‘potential’ developments (UC3) are also seen to account for 2742 additional trips in the AM peak and 3428 in the PM peak.

1.8 With the addition of committed and potential development trips to the base demand, only an additional 1386 and 1318 trips, AM and PM peaks, are added to reach overall growth forecasts for 2026 contained in Tempro.

1.9 The 2026 network includes committed proposals for the Health Campus Link and Colonial Way Extension. In addition, minor improvements were also identified to help accommodate additional demand associated with committed development. These include optimisation of traffic signals at a number of junctions, physical changes to the network at junctions along Hempstead Road and additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre.

1.10 With the network improvements identified, it is predicted that operation of the junction of Eastbury Road/Deacons Hill is likely to be cause for concern in future years, with increased delay compared to the base also predicted on approach to Rickmansworth in the morning peak and along Hempstead Road in the evening peak.

1.11 These concerns are highlighted in the following figures, showing the volume of traffic on key links as a percentage of the capacity of those links. The volume/capacity plots also highlight further links over, or close to, capacity which were not identified as changes to the base in Technical Note 2. This indicates that these links are also likely to be causes for concern in the base. These include the southbound approach to Bushey Arches in the morning peak and both on exit from the town centre on Rickmansworth Road and on the M25 Spur from Junction 19 in the evening peak.

2 Technical Note 3: 2026 LDF Sites

FIGURE 1.1 VOLUME/CAPACITY – AM PEAK – BASE + COMMITTED SCENARIO

3 Technical Note 3: 2026 LDF Sites

FIGURE 1.2 VOLUME/CAPACITY – PM PEAK – BASE + COMMITTED SCENARIO

4 Technical Note 3: 2026 LDF Sites

Base + Committed + Growth

1.12 Similar volume/capacity plots are also provided for the Base+Committed+Growth scenario. In the morning peak, the findings are similar to Figure 1.1 although we do see increased congestion on routes in and out of the Bushey Arches gyratory and also along the A41 outer orbital route.

1.13 In the evening peak, with unconstrained future growth, we predict volumes in excess of existing capacity on exit from Ascot Road and also show increasing volumes of flow along St Albans Road and Hempstead Road (outbound) and on the M25 between junctions 18 and 19.

1.14 Comparing the ‘Base+Committed+Growth’ assignment against the ‘Base+Committed’ only results gives an indication where additional future year traffic is likely to be focussed if there is little control over where that growth occurs. Figures 1.5 and 1.6 illustrate difference plots of demand flows between the two scenarios for the AM and PM peak respectively. The majority of links are green, as expected, showing an increase in flow with the additional demand. However, there are pockets of network, particularly around Leavesden in the morning peak, where rerouting is predicted to occur to such an extent that link flows are reduced, although these reductions are countered by large increases on adjacent links.

1.15 Closer inspection of assignments in the Leavesden area indicates that this part of the model is sensitive to minor changes in delay on competing rotes with very similar journey times, resulting in the ‘switch’ of flows from one route to another between different model runs. This is more a reflection on the model assignment techniques than any real difficulties within the network. The relatively strange re- routing effects shown in Figure 1.5 are largely removed if slightly more capacity is coded for the A405 Kingsway approach to the A41 North Western Avenue junction.

1.16 The majority of the increase is shown on the motorways which, given growth is relatively unconstrained and that the strategic network is most heavily trafficked, is not a surprise.

1.17 Perhaps more interestingly, the changes in delay on the network shown in Figures 1.7 and 1.8 , are relatively low and suggest that the model adjusted to best accommodate committed development demand, can also largely accommodate further growth to 2026.

1.18 As discussed above, if increased capacity is modelled at the A405/A41 junction, the high delays around Leavesden shown in the AM peak (Figure 1.7) are removed.

5

Technical Note 3: 2026 LDF Sites

FIGURE 1.3 VOLUME/CAPACITY – AM PEAK – BASE + COMMITTED + GROWTH SCENARIO

7 Technical Note 3: 2026 LDF Sites

FIGURE 1.4 VOLUME/CAPACITY – PM PEAK – BASE + COMMITTED + GROWTH SCENARIO

8 Technical Note 3: 2026 LDF Sites

FIGURE 1.5 DIFFERENCE PLOT – AM PEAK DEMAND FLOWS – IMPACT OF GROWTH TO 2026

9 Technical Note 3: 2026 LDF Sites

FIGURE 1.6 DIFFERENCE PLOT – PM PEAK DEMAND FLOWS – IMPACT OF GROWTH TO 2026

10 Technical Note 3: 2026 LDF Sites

FIGURE 1.7 DIFFERENCE PLOT –AM PEAK DELAY – IMPACT OF GROWTH TO 2026

11 Technical Note 3: 2026 LDF Sites

FIGURE 1.8 DIFFERENCE PLOT – PM PEAK DELAY – IMPACT OF GROWTH TO 2026

12 Technical Note 3: 2026 LDF Sites

Base + Committed + Potential + Growth (LDF Scenario)

1.19 With future growth focussed on those areas identified in the LDF as having potential deliver additional development, we see changes in the distribution of traffic across the network.

1.20 Figure 1.9 shows volume/capacity for the AM peak with future growth largely constrained to LDF sites. PM peak results are shown in Figure 1.10.

1.21 The main highlight in the AM peak results from more detailed modelling of the LDF sites around West Watford. In the PM peak the main benefits predicted from assigning growth to LDF sites is that we forecast less stress on the M25 J18-19 and we also see a change in pressures around the south and west of Rickmansworth and flows just reaching 100% of modelled capacity outbound on Stephensons Way.

1.22 Figure 1.11 shows the impact of focussed growth in the AM peak in terms of differences in flows on links when compared to unconstrained growth (Base + Committed + Growth). The difference plot shows reduction in flow on the M25 and M1 links implying that the growth is more self-contained within the study area when applied to potential allocations. A similar pattern is shown for the PM peak in Figure 1.12.

1.23 The main differences between the two peaks is that we again see significant re- routing around Leavesden in the AM peak, implying that the assignment is very sensitive to changes in journey time in this part of the network. In both peaks, we see increased demand for busy routes between Rickmansworth and Watford, particularly around Watford Business Park, but in the PM peak, where we have more trips associated with the potential sites, the impact is greater and also shown to extend beyond Rickmansworth along the A412 Uxbridge Road to the M25.

1.24 Figure 1.13 shows that the major re-routing around Leavesden in the AM Peak is a result of major delays around Kingsway which, as described earlier, can be addressed through minor increases in modelled capacity at the A405/A41 junction. Changes in delay elsewhere are small in comparison.

1.25 Changes in delay in the PM peak are isolated and relatively small, as shown in Figure 1.14.

1.26 Figures 1.15 and 1.16 also show total delay for the LDF scenario for the AM and PM peaks respectively. To highlight areas of concern, only those areas with delays in excess of 120 seconds are shown. For the AM peak, the delay in Leavesden is highlighted, and although not identified in the comparison of delay against the unconstrained growth scenario, we also see delays above 2 minutes on roads close to Watford Junction Station and on approaches to Rickmansworth.

1.27 In the PM peak delays correspond well with the volume/capacity analysis in that we see significant delay on Ascot Road, as well as delays along, and joining, Hempstead Road, at Eastbury Road/Deacon’s Hill and at Bushey Arches.

13 Technical Note 3: 2026 LDF Sites

FIGURE 1.9 VOLUME/CAPACITY – AM PEAK – BASE + COMMITTED + POTENTIAL + GROWTH SCENARIO

14 Technical Note 3: 2026 LDF Sites

FIGURE 1.10 VOLUME/CAPACITY – PM PEAK – BASE + COMMITTED + POTENTIAL + GROWTH SCENARIO

15 Technical Note 3: 2026 LDF Sites

FIGURE 1.11 DIFFERENCE PLOT – AM PEAK DEMAND – IMPACT OF GROWTH FOCUSSED IN POTENTIAL ALLOCATION SITES

16 Technical Note 3: 2026 LDF Sites

FIGURE 1.12 DIFFERENCE PLOT – PM PEAK DEMAND – IMPACT OF GROWTH FOCUSSED IN POTENTIAL ALLOCATION SITES

17 Technical Note 3: 2026 LDF Sites

FIGURE 1.13 DIFFERENCE PLOT – AM PEAK DELAY - IMPACT OF GROWTH FOCUSSED IN POTENTIAL ALLOCATION SITES

18 Technical Note 3: 2026 LDF Sites

FIGURE 1.14 DIFFERENCE PLOT – PM PEAK DELAY - IMPACT OF GROWTH FOCUSSED IN POTENTIAL ALLOCATION SITES

19 Technical Note 3: 2026 LDF Sites

FIGURE 1.15 DELAY (SECONDS) – AM PEAK – LDF SCENARIO

20 Technical Note 3: 2026 LDF Sites

FIGURE 1.16 DELAY (SECONDS) – PM PEAK – LDF SCENARIO

21

Technical Note 3: 2026 LDF Sites

1.28 This analysis above essentially concentrates on differences in traffic patterns between defined and undefined full development scenarios. The following diagrams show differences in link flows between the full LDF scenario, ie with potential sites for future development identified, and the Base+Committed. That is we focus on the impact of levels of growth that could be delivered through the LDF proposals for both Three Rivers and Watford.

1.29 Referring to the volume/capacity plots in Figures 1.9 and 1.10 and comparing to the results in Figures 1.1 and 1.2 we can see that, in the AM peak, pressures associated with the combined LDF proposals are focussed on Watford, with network stress in West Watford and around the Bushey Arches gyratory. In the PM peak we predict changes in stress patterns around south-west Rickmansworth and increased stress at Watford Business Park and outbound on St Albans Road.

1.30 Changes in link demand flows between the two scenarios are shown in Figures 1.17 and 1.18 for the AM and PM respectively.

1.31 For the AM peak, we should compare the output to Figure 1.5. The results are very similar in that we still see re-routing around Leavesden and westbound along Eastbury Road, but we do see smaller increases in flow on the motorway links, particularly the M25. The areas where increases are generally greater is around West Watford.

1.32 Similarly, the PM peak results should be compared to Figure 1.6. Not surprisingly, the majority of links are still green, indicating an increase in flow, but the increases on the M25 and M1 are not as great. The main areas of difference are around West Watford, Hempstead Road and the town centre in general where the bandwidths are wider, showing a greater concentration of development traffic in those areas. There is some PM peak re-routing on exit from Rickmansworth towards the M25, with more traffic using Uxbridge Road rather than Chorleywood Road.

23

Technical Note 3: 2026 LDF Sites

FIGURE 1.17 DIFFERENCE PLOT – AM PEAK DEMAND – IMPACT OF LDF SCENARIO

25 Technical Note 3: 2026 LDF Sites

FIGURE 1.18 DIFFERENCE PLOT – PM PEAK DEMAND – IMPACT OF LDF SCENARIO

26 Technical Note 3: 2026 LDF Sites

Cause of Problems

1.33 We have identified, in the sections above, a series of potential problems with highway capacity in future years. These can be summarised as:

I Eastbury Road/Deacons Hill I St Albans Road/Station Road I Bushey Arches I Ascot Road/Whippendell Road I Sheepcot Lane/St Albans Road (AM peak) I A412 Uxbridge Road/A404 Riverside Drive (AM peak) I Hempstead Road/Courtlands Drive (PM peak) I Hempstead Road/Langley Road (PM peak) I M25 Spur towards Hunton Bridge roundabout (PM peak)

1.34 To assess whether potential problems can be associated with particular development scenarios, the following diagrams show the pattern of trips associated with each of the committed and potential development sites.

FIGURE 1.19 COMMITTED DEVELOPMENT TRIPS (USER CLASS 2) – AM PEAK

27 Technical Note 3: 2026 LDF Sites

FIGURE 1.20 LDF DEVELOPMENT TRIPS (USER CLASS 3) – AM PEAK

1.35 In Figure 1.19 we see that the greatest increases are towards the Health Campus, with a significant increase in flow from the M1 and along Stephenson Way. These are not routes obviously impacting on the problem areas listed above.

1.36 Figure 1.20 shows the impact of trips associated with potential LDF sites. Here we can link increases in demand to some of the problem areas, seeing significant increases forecast for Ascot Road, Hempstead Road to Langley Road and through the St Albans Road/Station Road junction.

1.37 The impact of committed development trips in the PM peak is very similar to Figure 1.19. However, Figure 1.21 shows the impact of LDF sites and we see greater increases along Hempstead Road, which are likely to be a cause of the problems at Courtlands Drive and Hunton Bridge.

1.38 The other problem areas of Eastbury Road/Deacons Hill, Bushey Arches and the western side of Rickmansworth are all areas of existing congestions, expected to worsen with growth to 2026.

28 Technical Note 3: 2026 LDF Sites

FIGURE 1.21 LDF DEVELOPMENT TRIPS (USER CLASS 3) – PM PEAK

Strategic Highway Routes

1.39 Tables 1.1 and 1.2 below show the change in flow on the motorway network between each model scenario.

TABLE 1.2 STRATEGIC NETWORK – MOTORWAY LINKS – DEMAND FLOW

Motorway Links AM Peak PM Peak Base+Com Base+Com Base+Com Base+Com Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 s of J17 9571 9625 10380 9943 9822 9719 10551 10110 17-18 10367 10154 11038 10644 10168 10332 11087 10840 18-19 10751 10887 11791 11646 11073 11316 12230 11735 19 spur 2766 2806 2859 3067 1640 1373 1349 1359 19-20 7985 8081 8933 8577 9434 9943 10881 10375 20-21 8317 8064 9091 8654 9094 9265 9959 9581 e of J21 9484 9575 10341 9916 9848 9942 10799 10271 M1 n of M25 8935 9681 10501 10222 9556 9785 10594 10335 M25-J6 5862 6312 6741 6658 5381 5608 6054 5977 6-5 8294 8827 4087 9670 8742 9201 9973 9867 s of 5 6203 6194 6701 6487 6617 6735 7291 6877 TABLE 1.3 STRATEGIC NETWORK – MOTORWAY JUNCTIONS – DEMAND FLOW

Motorway Junctions AM Peak PM Peak Base+Com Base+Com Base+Com Base+Com Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 J17 11193 11048 11942 11537 11079 11151 11972 11871 J18 12510 11755 13713 13557 12420 12642 13662 13148 J19 10751 10887 11791 11646 11073 11316 12230 11734 J20 9909 9597 10657 10238 11662 12379 13454 12903 M25/M1 14808 15358 16775 16331 15345 15776 16952 16478 M1 J6 10431 11272 12228 12205 11099 11833 12868 12687 J5 10688 11039 11943 11765 11161 11643 12601 12298

29 Technical Note 3: 2026 LDF Sites

1.40 In both peaks, we see only modest changes in flow on the M25 between the base scenario and ‘Base+Committed’ although greater increases are predicted for the M1, north of Junction 5.

1.41 Adding unconstrained growth, we see increases in flows through junctions of between 7% and 17% in the morning peak, the greatest increases being through Junction 6 of the M1. With growth constrained to LDF sites, we generally see a 2- 3% reduction in the increased demand through each junction, except M1 J6 where the increase remains 17% above the base.

1.42 In the PM peak we see a similar picture where again M1 J6 sees the greatest increase in through demand at 16% in the unconstrained scenario, with the remaining junctions seeing increases of between 8% and 15%. Again, under the LDF scenario we see general reductions of up to 4% over the unconstrained growth scenario.

1.43 A more detailed breakdown of changes in flow at motorway junctions is provided in Appendix A. For each scenario, flows on each approach to the junction are provided, giving an indication of which movements are most impacted by each different growth scenario.

1.44 In all cases it should be noted that while the motorway network is included in the highway model, these routes form the edges of the model and are not modelled in the same level of detail as the more central parts of the model area and the impacts of queues and delay are not modelled in detail. We therefore have less confidence in the flows quoted for these outer ‘buffer’ parts of the model and recommend that it is the absolute changes in flow that should be considered, rather than the actual flows quoted.

1.45 As such, while the Watford SATURN model is able to provide forecasts of changes in flow at motorway junctions associated with committed and proposed development sites to 2026, it is recommended that these absolute changes in flow are in turn reflected in more specific models of the strategic network, such as the M25 Assignment Model, before any significant conclusions can be drawn.

Public Transport Supply

1.46 Development related trips generally spread across the network, and main radial routes into and out of the town, particularly from the north and west, are well served by existing bus services, linking Watford and Rickmansworth to surrounding towns. A summary of peak hour services along each key radial is provided below in Table 1.4.

1.47 Although not shown in Table 1.4, there are also approximately 4 buses per hour linking Watford Business Park to the town centre (Service W30) and Watford Junction. There is scope for this service to help accommodate some of the extra demand to the business park as it expands. However, the current service routes via Watford Metropolitan station and there might be merit in instead routing the service along Rickmansworth Road to offer improved journey times, particularly if the Croxley Rail Link proposals are delivered, which will result in closure of the station on the Metropolitan Line.

30 Technical Note 3: 2026 LDF Sites

1.48 It is also worth noting that the Croxley Rail Link proposals themselves introduce new stations at both Ascot Road and at the Health Campus, which will provide additional public transport options to each of these key employment destinations.

1.49 Similarly, it can be implied that these model results represent a worst case given that no account is made of expected reductions in flow on local highways as a result of the Croxley Rail Link (CRL) scheme nor Abbey Line improvements. It is worth noting that for CRL alone, the supportin Transport Assessment indicates a predicted reduction of some 287 peak hour trips from the network following introduction of the scheme as drivers change mode from the car to rail. These reductions in flow offer moderate improvement in future year operational conditions at both the Rickmansworth Road/Ascot Road and Ascot Road/Whippendell Road junctions.

TABLE 1.4 EXISTING BUS ROUTE SUMMARY – KEY RADIALS

Corridor Service No Frequency

Hempstead Road 318 2 per hour 500 Up to 4 per hour (directional) 550 2 per hour T2 2 per hour

St Albans Road 1 2 per hour 320 2 per hour 321 Approx 3 per hour 621 Hourly 724 (Limited Stop) Hourly

London Road 142 4 per hour 258 4 per hour

Eastbury Road 2 2 per hour 8 2 per hour

Rickmansworth Road, 320 2 per hour west of Ascot Road 321 Approx 3 per hour 336 Hourly 352 Hourly 724 Limited Stop) Hourly

Uxbridge Road, west of 320 2 per hour Rickmansworth 321 Approx 3 per hour 724 (Limited Stop) Hourly R21 Hourly

Chorley Wood Road, 336 Hourly west of Rickmansworth

31 Technical Note 3: 2026 LDF Sites

Potential solutions

1.50 As outlined in Technical Note 2, the 2026 network includes committed proposals for the Health Campus Link and Colonial Way Extension. In addition, minor improvements were also identified to help accommodate additional demand associated with committed development. These include optimisation of traffic signals at a number of junctions, physical changes to the network at junctions along Hempstead Road and additional capacity at the A412/A404 roundabout to the west of Rickmansworth Town Centre. These additional improvement are all minor scale and relatively low cost.

1.51 Beyond these improvements initially identified, assessment of increased growth to 2026 has shown additional areas of network stress we might expect as either the LDF scenario, or the unconstrained growth scenario, is delivered. Mitigating future growth will likely be achieved through a combination of highway improvements and increased opportunity for public transport use.

1.52 Taking public transport first, future developments should each have targets set out to ensure levels of public transport use, either through better promotion, subsidised ticket prices or improvements to specific services. However, two of the main attractors in future years will be Watford Business Park and the Health Campus. There is scope for the route between the business park and the town centre to help accommodate some of this extra demand as the business park expands. There might also be scope to re-route the service to provide a more direct link along Rickmansworth Road, particularly if the Croxley Rail Link proposals are delivered, which will result in closure of the station on the Metropolitan Line. Consideration might also be given to providing a similar route between the business park and Rickmansworth.

1.53 It is also worth noting that the Croxley Rail Link proposals themselves introduce new stations at both Ascot Road and at the Health Campus, which will provide additional public transport options to each of these key employment destinations.

1.54 For highways, there are a number of areas, such as Bushey Arches and at the Eastbury Road/Deacons Hill and St Albans Road/Station Road junctions, where land constraints make it very costly to introduce additional physical capacity.

1.55 At Eastbury Road/Deacons Hill, it seems feasible to segregate left turning traffic out of Deacons Hill into a new lane, but any further widening or increase in capacity would require land –take, and possible demolition of properties. It is assumed that all movements should be retained.

1.56 At St Albans Road/Station Road, the most likely improvement might be to accommodate two full northbound lanes out of the junction, allowing outbound traffic to pass through the junction in both lanes. A review of parking on the northbound exit to the junction should also be considered.

1.57 Many studies of the Bushey Arches gyratory have been undertaken. Capacity is essentially constrained by the railway arches and any physical improvement, through widening the arches would be costly.

32 Technical Note 3: 2026 LDF Sites

1.58 Capacity of the M25 spur approach to the Hunton Bridge roundabout could be achieved through widening the approach and circulatory capacity and/or signalisation of this approach, similar to the signalisation from the North Western Avenue approach.

1.59 Increased capacity can likely be provided at the St Albans Road/ Sheepcot Lane junction through further signal optimisation.

Conclusions

1.60 This Technical Note looks specifically at growth to 2026, constrained by Tempro, under two scenarios:

I Base + Committed Development + Background Growth to 2026 I Base + Committed and Potential Developments + Background Growth to 2026 (LDF Scenario)

1.61 With ‘Base+Committed+Growth’, there is little control over where the growth occurs. The majority of routes show an increase in flow with the additional demand and the majority of the increase is shown on the motorways which, given growth is relatively unconstrained and that the strategic network is most heavily trafficked, is not a surprise.

1.62 Perhaps more interestingly, the changes in delay on the network are relatively low and suggest that the model adjusted to best accommodate committed development demand, can also largely accommodate further growth to 2026.

1.63 With future growth focussed on those areas identified in the LDF as having potential deliver additional development, we see changes in the distribution of traffic across the network. In both peaks there is a reduction in flow on the M25 and M1 links implying that the growth is more self-contained within the study area when applied to potential allocations. We see increased demand for busy routes between Rickmansworth and Watford, but in the PM peak, where we have more trips associated with the potential sites, the impact is greater and also shown to extend beyond Rickmansworth along the A412 Uxbridge Road to the M25

1.64 Comparing the LDF scenario against ‘base+committed’ only, we see pressures, in the AM peak, focussed on Watford, with network stress in West Watford and around the Bushey Arches gyratory. In the PM peak we predict changes in stress patterns around south-west Rickmansworth and increased stress at Watford Business Park and outbound on St Albans Road.

1.65 When trips associated with potential LDF sites are assessed independently, we can link increases in demand to some of the problem areas identified, seeing significant increases forecast for Ascot Road, Hempstead Road ( as far as Langley Road) and through the St Albans Road/Station Road junction in the AM peak. In the PM peak we also forecast greater increases along Hempstead Road, which are likely to be a cause of the problems at Courtlands Drive and Hunton Bridge.

1.66 The other problem areas of Eastbury Road/Deacons Hill, Bushey Arches and the western side of Rickmansworth are all areas of existing congestions, expected to worsen with growth to 2026.

33 Technical Note 3: 2026 LDF Sites

1.67 Unconstrained growth to 2026 is predicted to add between 7-17% traffic to the motorway junctions within the study area, with M1 Junction 6 seeing the greatest increase. With growth constrained to LDF sites, we generally see a 2-3% reduction in the AM peak, and up to 4% in the PM peak.

1.68 However, it should be noted that while the motorway network is included in the highway model, these routes are not modelled in the same level of detail as the more central parts of the model area and queues and delay are not validated. We therefore have less confidence in the flows quoted for these outer ‘buffer’ parts of the model and recommend that it is the absolute changes in flow that should be considered, rather than the actual flows quoted.

1.69 Development related trips generally spread across the network, and main radial routes into and out of the town, particularly from the north and west, are well served by existing bus services, linking Watford and Rickmansworth to surrounding towns. Also, the Croxley Rail Link proposals introduce new rail stations at both Ascot Road and at the Health Campus, which will provide additional public transport options to each of these key employment destinations.

1.70 Similarly, it can be implied that these model results represent a worst case given that no account is made of expected reductions in flow on local highways as a result of the Croxley Rail Link (CRL) scheme nor Abbey Line improvements.

1.71 Growth in traffic on the network to 2026 will both add to pressures at locations where congestion is already a cause for concern, and introduce new concerns. The following table brings together the various proposals put forward, both to accommodate traffic associated with committed development proposals and beyond. For each solution, a scale of costs is also provided, although this must at this stage be taken as an indication only. Further detailed design and consideration of land costs would be needed to validate these costs.

TABLE 1.5 POTENTIAL FUTURE YEAR MITIGATION SUMMARY

Definition Description Funding / Cost

Major Schemes

Health Campus Link New link from development to Dalton Way Developer led via Wiggenhall Road

Colonial Way Link Extension of Colonial Way to St Albans Rd Funding bid

Croxley Rail Link New rail link from Croxley to Watford Funding bid Junction Station, inc new stations at Ascot Rd and Health Campus

Committed Developments

Signal optimisation Clarendon Road/ St Johns Road Low cost Hempstead Road/ Langley Way Exchange Road/ Market Street

Capacity improvement Increased circulatory capacity A412/A404 <£1m roundabout

34 Technical Note 3: 2026 LDF Sites

RT lanes into/out of Glen Way and Grove <£0.25 Mill La at junctions with Hempstead Road

Additional Mitigation

Bus re-routing Re-route W30 service along Low cost Rickmnasworth Rd rather than via Watford Met Station

New bus services New service between Watford Business <£1m (subsidy?) Park and Rickmansworth

Signal optimisation St Albans Road/ Sheepcot Lane Low cost

Capacity improvement M25 spur approach to Hunton Bridge rbt – ~£1m widening approach/circulation or signalisation

Eastbury Road/ Deacons Hill – possible LT <£1m up to £5m+ lane from Deacons Hill or major land-take

St Albans Rd/ Station Rd – possible 2-lanes <£1m northbound out of junction & review of parking

Bushey Arches – major scheme? £10m+

Filenames I AM Peak . Networks: AM26NET_COM_GROWTH.net & AM26NET_COM_POT_GROWTH.net . Matrices: AM_base+committed+growth.ufm & AM_base+com+pot+growth.ufm

I PM Peak . Networks: PM26NET_COM_GROWTH2b.net & PM26NET_COM_POT_GROWTH2b.net . Matrices: PM_base+committed+growth.ufm & PM_base+com+pot+growth.ufm

35

Technical Note 3: 2026 LDF Sites

APPENDIX

A

MOTORWAY JUNCTIONS

Appendix A

Technical Note 3: 2026 LDF SitesTechnical Note 3: 2026 LDF Sites

A1 MOTORWAY JUNCTIONS

Model Flows

A1.1 There follows a series of tables showing flows through each motorway junction, in terms of in and out flow on each approach, for each model scenario.

A1.2 The caveats in relation to the reliability of flows in the outer ‘buffer’ parts of the network are noted in paragraph 1.42 of the main note, and it is recommend that it is the changes in flow that should be considered, rather than the actual flows quoted.

A1.3 Flows are provided for the following Junctions:

I M25 Junctions 17 to M25 I M1 Junction 5 and 6

M25 Junction 17

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 J17 M25 (south) IN 5461 5475 5897 5656 5093 4973 5402 5232 OUT 4110 4150 4483 4287 4729 4746 5149 4878 Long Lane IN 430 272 315 306 168 171 185 233 OUT 371 256 280 269 243 254 273 263 M25 (north) IN 4756 4695 5104 4937 4820 4894 5329 5032 OUT 5611 5459 5934 5707 5348 5438 5758 5808 Denham Way IN 546 606 626 638 998 1113 1056 1374 OUT 1100 1183 1245 1273 757 712 792 921 TOTAL IN 11193 11048 11942 11537 11079 11151 11972 11871 OUT 11192 11048 11942 11536 11077 11150 11972 11870 A1.4 Total flows through the M25 Junction 17 are only marginally affected by the addition of committed development trips, in fact re-routing in the model results in a slight decrease in the AM peak. With both unconstrained growth and the LDF scenario (Base+Com+Pot+Gr), junction flows are increased, with growth constrained to LDF sites having less effect in the PM peak.

A1.5 The LDF scenario shows significant impact on Denham Way in the PM peak, with two-way flows increasing by 31% over the ‘Base+Committed’. The corresponding increase in the Am peak is 16%.

M25 Junction 18

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 J18 M25 (south) IN 5611 5459 5934 5707 5348 5438 5758 5808 OUT 4756 4695 5104 4937 4820 4894 5329 5032 A404 IN 975 1169 1293 1360 941 981 1066 997 Rickmansworth Rd OUT 953 1101 1191 1254 876 919 1004 1019 M25 (north) IN 4942 5029 5430 5356 5110 5253 5703 5427 OUT 5809 5858 6361 6290 5963 6063 6527 6308 A404 Chorleywood IN 982 988 1056 1134 1021 970 1135 916 Rd OUT 992 992 1058 1075 762 767 801 789 TOTAL IN 12510 12645 13713 13557 12420 12642 13662 13148 OUT 12510 12646 13714 13556 12421 12643 13661 13148

Appendix A Technical Note 3: 2026 LDF SitesTechnical Note 3: 2026 LDF Sites

A1.6 At Junction 18, we see a very consistent pattern between scenarios for each of the AM and PM peaks. Flows on all approaches are reduced between the unconstrained and LDF scenarios in the PM peak. In the AM peak, the LDF scenario shows reduced M25 flows, but increases in side road demand.

M25 Junction 19 (M25 Spur)

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 J19 M25 (south) IN 5809 5858 6361 6290 5963 6063 6527 6308 OUT 4942 5029 5430 5356 5110 5253 5703 5427 M25 (north) IN 3403 3430 3654 3505 4455 4410 4797 4561 OUT 4582 4651 5279 5074 4979 5533 6084 5814 M25 Spur IN 1539 1599 1776 1851 655 843 906 865 OUT 1227 1207 1083 1216 985 530 443 494 TOTAL IN 10751 10887 11791 11646 11073 11316 12230 11734 OUT 10751 10887 11792 11646 11074 11316 12230 11735 A1.7 Junction 19 of the M25 provides a spur to the A41/A411 at Hunton Bridge. The spur connects to and from M25 south only.

A1.8 In the AM peak, total flows are only marginally increased with the additional of committed development trips and it is M25(south) that has the greatest impact with future growth, with the impact only slightly dampened by the more constrained growth promoted through the LDF scenario.

A1.9 In the PM peak, the model output suggests a reduction in flow on the spur, awy from the M25, which is likely to be a result of re-routing of trips from external zones, as we see correspondingly more modelled ‘outbound’ on the M25 (north).

M25 Junction 20

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 J20 M25 (south) IN 4582 4651 5279 5074 4979 5533 6084 5814 OUT 3403 3430 3654 3505 4455 4410 4797 4561 A41 (north west) IN 176 175 192 197 244 325 369 339 OUT 229 280 291 287 698 759 808 806 A4251 Watford Rd IN 629 538 603 554 712 804 867 840 OUT 595 260 287 264 698 739 807 783 M25 (north) IN 3711 3382 3711 3488 4753 4732 5051 4868 OUT 4606 4682 5380 5166 4341 4533 4908 4713 A41 (south east) IN 811 851 872 925 974 985 1083 1042 OUT 1077 944 1045 1016 1468 1938 2134 2039 TOTAL IN 9909 9597 10657 10238 11662 12379 13454 12903 OUT 9910 9596 10657 10238 11660 12379 13454 12902 A1.10 As development is added over time, the greatest impact on AM peak flow into Junction 20 is from M25(south), with corresponding increases to M25 (north), suggesting that the main impact at this junction is on northbound through traffic. This pattern is reflected in the PM peak to some extent, although we also see increases in demand towards Watford on the A41 (south west).

Appendix A Technical Note 3: 2026 LDF SitesTechnical Note 3: 2026 LDF Sites

M25/M1 Junction

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M25 / M1 M25 (west) IN 4606 4682 5380 5166 4341 4533 4908 4713 OUT 3711 3382 3711 3488 4753 4732 5051 4868 M1 (north) IN 4506 4821 5156 5070 4839 4919 5320 5214 OUT 4429 4860 5245 5152 4717 4866 5274 5121 M25 (east) IN 4723 4706 5133 4873 4899 4878 5209 5038 OUT 4521 4599 5279 5083 4870 5062 5483 5273 M1 (south) IN 2345 2472 2654 2636 2821 2969 3212 3137 OUT 3517 3840 4087 4022 2560 2639 2842 2840 TOTAL IN 16180 16681 18323 17745 16900 17299 18649 18102 OUT 16178 16681 18322 17745 16900 17299 18650 18102 A1.11 The M1 (north) and M25 (east) arms of the junction are at the very edge of the highway model and provide links to and from external zones. With trips from future development we see increases in demand in both directions on the M1(north). This pattern is largely repeated for M25(east) although the greater impact eastbound, away from the study area, in both peaks.

A1.12 There is also an increase in demand on the M25 (south) arm under each scenario. In all cases, demand with the LDF scenario is less than we would expect under unconstrained growth.

M1 Junction 6

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M1 J6 M1 (south) IN 3201 3304 3638 3626 5095 5247 5750 5608 OUT 5093 5523 5962 6044 3647 3954 4223 4259 A405 (south west) IN 1553 1744 1661 1771 1265 1362 1424 1424 OUT 1619 1773 1977 1942 2938 3065 3462 3281 M25 (north) IN 3517 3840 4087 4022 2560 2639 2842 2840 OUT 2345 2472 2654 2636 2821 2969 3212 3137 A405 (north east) IN 2160 2384 2842 2786 2179 2585 2852 2815 OUT 1374 1505 1635 1583 1694 1846 1971 2010 TOTAL IN 10431 11272 12228 12205 11099 11833 12868 12687 OUT 10431 11273 12228 12205 11100 11834 12868 12687 A1.13 The difference between unconstrained growth and the LDF scenario is less pronounced at this than other junctions, although the general pattern is still a reduction in demand through the junction for the LDF scenario.

A1.14 Total flows are similar for each time period under each scenario, with growth between the base and LDF scenarios of around 14-17%.

A1.15 Under each future year scenario, we see significant increase in forecast demand on the A405(north-east) arm, to and from the ST Albans area.

Appendix A Technical Note 3: 2026 LDF SitesTechnical Note 3: 2026 LDF Sites

M1 Junction 5

Approach Arm IN/OUT AM Peak PM Peak Motorway Base+Com Base+Com Base+Com Base+Com Junction Base Base+Com +Gr +Pot+Gr Base Base+Com +Gr +Pot+Gr M1 J5 M1 (south) IN 2315 2307 2490 2402 3890 4013 4360 4128 OUT 3888 3887 4211 4085 2727 2722 2931 2749 A41 slip roads IN 1811 1715 1753 1656 1132 1180 1403 1317 (south) OUT 622 623 918 817 1348 1536 1613 1557 A4008 IN 1391 1447 1534 1584 2037 2005 2105 2104 Stephensons Way OUT 2801 3088 3109 3171 1598 1817 1963 2096 A41 slip roads IN 78 47 204 79 455 491 510 490 (north) OUT 176 137 67 67 392 322 345 288 M1 (north) IN 5093 5523 5962 6044 3647 3954 4223 4259 OUT 3201 3304 3638 3626 5095 5247 5750 5608 TOTAL IN 10688 11039 11943 11765 11161 11643 12601 12298 OUT 10688 11039 11943 11766 11160 11644 12602 12298 A1.16 M1 Junction 5 is a complex junction, combining access to and from central Watford via Stephensons Way as well as providing connections to the A41 Orbital Route. All approaches to the junction are managed by traffic signals.

A1.17 The total flows through the junction follow a similar pattern to Junction 6 in that differences between unconstrained growth and the LDF scenario are less pronounced at this than other junctions, and total flows are similar for each time period under each scenario, with growth between the base and LDF scenarios of around 10%.

A1.18 The caveat relation to the reliability of absolute flow values in the outer buffer parts of the model appears to apply at this junction with forecast flows entering and leaving the northern section of the A41 seeming low in the AM peak.

Appendix A

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Technical Note 3: 2026 LDF Sites

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 224042/01

ISSUE HISTORY

Issue No. Date Details

1 10 Oct 11 Draft 2 04 Nov 11 Revised Draft

3 December 2011 Final

REVIEW

Originator Steve Oliver

Other Contributors Paul Robinson

Review by: Print Steve Oliver

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

L:\Projects\224\0\42\01\Outputs\Working Notes\Technical Note 3\Tech Note 3v4 - 24Dec11.docx

Control Sheet Three Rivers and Watford LDF

Technical Note 4: Secondary Schools Test Technical note

October 2011

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall West Riding House Pegs Lane 67 Albion Street Hertford Leeds LS1 5AA SG13 8DN +44 (0)113 389 6400 www.steerdaviesgleave.com

Technical Note 4: Secondary Schools Test

CONTENTS

1 TASK 4: SECONDARY SCHOOLS TEST ...... 1 Introduction ...... 1 Modelling Assumptions ...... 2 Assignment of Trips ...... 2 Impact Assessment ...... 3 Conclusion ...... 3

TABLES

Table 1.1 School Traffic Distribution (%) ...... 1 Table 1.2 Calculation of TRips Leaving Each Site (8-9am) ...... 2

Contents

Technical Note 4: Secondary Schools Test

1 Task 4: Secondary Schools Test

Introduction

1.1 The purpose of this Technical Note is to describe the potential impact on the local highway network of proposals for two new secondary schools in Three Rivers. Each will have 6-8 forms of entry and accommodate approximately 1200 pupils. It is currently expected that these will be located in the following areas:

I Mill End/Maple Cross – land adjacent to the A404/A412 roundabout; and I Croxley Green – land north-west of Baldwins Lane 1.2 A preliminary highways and access feasibility study1 has been completed by Stomor Civil Engineering Consultants. In this report the sites are referred to as Site S(a)/S(b) and Site S(d) respectively.

1.3 The report provides forecasts of AM peak (8-9am) trips to each school as follows:

I Site S(a)/S(b) 256 car trips I Site S(d) 207 car trips 1.4 In addition, Stomor provides an estimate of the numbers of those trips related to staff on any given day. This is calculated as 70% of total staff trips (134) equal to 94 staff trips to each site.

1.5 The report also provides forecasts of the likely origins of staff/pupil trips. These vary by site and are summarised in Table 1.1.

TABLE 1.1 SCHOOL TRAFFIC DISTRIBUTION (%)

Origin Site S(a)/S(b) Site S(d) Mill End/ Maple Cross Croxley Green

Rickmansworth 17% 9%

Croxley Green 19% 7%

North Watford 20% 17%

West Watford 18% 41%

Chorleywood 3% 2%

Maple Cross 2% 3%

Northwood & Oxhey 11% 12%

“Further afield” 10% 10%

1 Highways and Access Feasibility Study for South West Herts Secondary Schools, August 2011

1 Technical Note 4: Secondary Schools Test

Modelling Assumptions

1.6 Each school has been added to the model as a new zone: Zones 500 for Site S(a)/S(b) and 501 for Site S(d). It is assumed that both new schools will be delivered.

1.7 Zone 500 has been connected directly onto the A404/A412 roundabout, to reflect the possibility of the school actually being developed on one of two potential sites. For the Croxley Green site, zone 501 has been connected to the network via a new link introduced off Baldwins Lane.

1.8 All trips to each school are assumed to arrive between 8am and 9am in the morning. The analysis has only been undertaken for the morning peak, on the basis that the end of the school day precedes the evening peak.

1.9 As well as trips to the school in the morning peak, we must also assume that all non-staff trips involve the drop-off of one or more pupil to the school.

1.10 Given the lack of information available to more accurately model the onward trip, it has been assumed that 75% of those trips return to their home origin, the rest not setting off until after 9am. The calculation of the number of trips that also depart from the school in the morning peak is provided below.

TABLE 1.2 CALCULATION OF TRIPS LEAVING EACH SITE (8-9AM)

Site S(a)/S(b) Site S(d) Mill End/ Maple Cross Croxley Green

Total Trips 256 207

Staff Trips 94 94

Drop-off 162 113

AM departures (75% drop-off) 112 85

1.11 An alternative assumption might be that the pupil drop-off is part of a longer trip, say from home to work. However, our working assumption is based on a lack of more detailed information at this stage and it is assumed that a more detailed assessment will be included with any future planning application.

Assignment of Trips

1.12 The Stomor report provides additional information with regards to the distribution assumptions summarised in Table 1.1. As well as the origin of the trip, forecasts of routes expected to be used are also provided.

1.13 The SATURN model does not allocate trips to routes, but instead allocates trips from one zone to another. As such, within the model we make our best attempt to match the Stomor distributions, but must rely on model to assign these trips to the network and be advised by the model in terms of final routings.

1.14 The modelled routes offer a good representation of the Stomor forecasts, with the main differences outlined below for each site.

2 Technical Note 4: Secondary Schools Test

I Site S(a)/S(b) – the West Watford origins are routed via Tolpits Lane rather than Rickmansworth Road, and all the North Watford trips are assigned to the M25, rather than some (40%) routing via the town centre as Stomor predicts. I Site S(d) – all arrivals from the west assign via Winton Drive, rather than split between Winton Drive, Green Lane and Baldwins. This potentially underestimates impacts at the Baldwins Lane roundabout, however:

1.15 In each case the model influences seem reasonable. 1.16 Trip departing from each site are modelled to reflect a mirror of arrival patterns.

Impact Assessment

1.17 The impact of the school trips are assessed against results from the ‘Base+Committed_Potential+Growth’ (LDF) scenario as defined in Technical Note No3. The main areas of difference assessed are delays and queues at junctions.

1.18 The findings indicate that we are able to separate the results by the location of the new school.

1.19 Differences in model delay are provided in Figure 1.1, and model queues in Figure 1.2. These can be summarised as follows:

I Site S(a)/S(b) – here we show further increases in delay at the A404/A412 roundabout, to the west of Rickmansworth centre. We see additional queues (+15 vehicles) and longer delays (+43 seconds) from the south-east, along with smaller impacts from the west. However, this is a location already highlighted for future improvements as part of the work detailed in Technical Note No3, hence any future work here should consider additional impacts from the school. I Site S(d) – the impacts are not shown for Baldwins Lane, or other routes in close proximity to the school, but instead we indicate additional queues and delays (approximately 60 seconds) on both Rickmansworth Road and Whippendell Road, to the east of the Ascot Road junction. These delays are indicated in each direction, both to and from the school site

Conclusion

1.20 The modelling does not show any major increases in stress on the network. 1.21 Any future analysis of the A412/A404 roundabout should consider additional impacts of school trips.

1.22 It is predicted that Site S(d) will generate relatively small increases in queues and delay on both Rickmansworth Road and Whippendell Road.

3

Technical Note 4: Secondary Schools Test

FIGURE 1.1 DIFFERENCES IN MODEL DELAY (SECONDS)

FIGURE 1.2 DIFFERENCE IN MODEL QUEUES (VEHICLES)

1

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Technical Note 4: Secondary Schools Test

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 224042/01

ISSUE HISTORY

Issue No. Date Details

1 28 October 2011 Draft

REVIEW

Originator Steve Oliver

Other Contributors

Review by: Print

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

L:\Projects\224\0\42\01\Outputs\Working Notes\Technical Note 4\Draft Tech Note 4 - 26Oct11.docx

Control Sheet Three Rivers and Watford LDF

Technical Note 5: Infrastructure Sensitivity Tests

Technical note December 2011

Prepared for: Prepared by: Hertfordshire County Council Steer Davies Gleave County Hall West Riding House Pegs Lane 67 Albion Street Hertford Leeds LS1 5AA SG13 8DN +44 (0)113 389 6400 www.steerdaviesgleave.com

Technical Note 5: Infrastructure Sensitivity Tests

CONTENTS

1 TASK 5: INFRASTRUCTURE SENSITIVITY TESTS ...... 1 Introduction ...... 1 Health Campus Link ...... 2 Colonial Way Extension ...... 10

FIGURES

Figure 1.1 Health Campus Link ...... 1 Figure 1.2 Colonial Way Link ...... 2 Figure 1.3 Morning Peak – Distribution of Trips To the Site ...... 4 Figure 1.4 Morning Peak – Distribution of Trips From the Site ...... 5 Figure 1.5 Evening Peak – Distribution of Trips To the Site ...... 5 Figure 1.6 Evening Peak – Distribution of Trips From the Site ...... 6 Figure 1.7 AM Peak – To the Site – No Health Campus Link Road ...... 6 Figure 1.8 AM Peak – From the Site – No Health Campus Link Road ...... 7 Figure 1.9 AM Peak – Difference in Demand Flows – No HCL ...... 8 Figure 1.10 PM Peak – To the Site – No Health Campus Link Road ...... 8 Figure 1.11 PM Peak – From the Site – No Health Campus Link Road ...... 9 Figure 1.12 Morning Peak – Distribution of Trips Using CWE - Eastbound ...... 11 Figure 1.13 Morning Peak – Distribution of Trips Using CWE - Westbound ...... 12 Figure 1.14 Evening Peak – Distribution of Trips Using CWE - Eastbound ...... 12 Figure 1.15 Evening Peak – Distribution of Trips Using CWE - Westbound ...... 13 Figure 1.16 AM Peak – Difference in Demand Flows – No CWE ...... 14 Figure 1.17 PM Peak – Difference in Demand Flows – No CWE ...... 14 Figure 1.18 AM Peak – Difference in Model Delay – No CWE ...... 15 Figure 1.19 PM Peak – Difference in Model Delay – No CWE ...... 16

TABLES

Table 1.1 Health Campus Development Trip Assumptions ...... 3 Table 1.2 Health Campus Link - Forecast Flow (2026) ...... 3 Table 1.3 Watford Junction Development Trip Assumptions ...... 10 Table 1.4 Colonial Way Extension – Forecast Flow (2026) ...... 11

Contents Technical Note 5: Infrastructure Sensitivity Tests

Contents Technical Note 5: Infrastructure Sensitivity Tests

1 Task 5: Infrastructure Sensitivity Tests

Introduction

1.1 The 2026 model network includes proposals for both the Health Campus Link and Colonial Way Extension.

I Health Campus Link . Connecting Dalton Way to the Health Campus site via Wiggenhall Road . Left-in/left-out junction provided at Dalton Way (one-way operation) . New signalised junction with Wiggenhall Road (use of the link road restricted to Health Campus trips)

I Colonial Way Extension . Connecting Colonial Way from its junction with Imperial Way to St Albans Rd . All moves signalised junction with St Albans Road . New rear entrance to Watford Junction Station car parks, forming a new signalised junction with Colonial Way Extension

1.2 The schematic location of each scheme is shown in Figures 1.1 and 1.2.

FIGURE 1.1 HEALTH CAMPUS LINK

1 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.2 COLONIAL WAY LINK

1.3 There remain doubts over the delivery of each scheme and, as such, two separate sensitivity tests have been undertaken; one without the Health Campus Link and one without the Colonial Way Extension. A combined test excluding both schemes has not been carried out given the minimal interaction between each scheme.

1.4 In simple terms, for each test, we assess how many trips use the link, who those people are, where they go if the link was not available and whether the re- assignment is likely to cause additional problems elsewhere on the network.

Health Campus Link

1.5 The Health Campus Link (HCL) test assumes the section between Wiggenhall Road and Dalton Way is not constructed, yet a new signal controlled access junction with Wiggenhall Road is still provided.

1.6 At the access junction, the same stage timings as before are used. Given that the HCL approach operated within the same stage as departures from the development site, this is a reasonable assumption.

1.7 HCL has been modelled to provide direct access to and from the main elements of the Health Campus site; the hospital itself, hotel and offices. The residential elements are modelled as separate entities with access from Cardiff Road. With reference to Technical Note 2: Future Year Model Development, the total trips assigned to the Health Campus development are repeated in Table 1.1 below.

2 Technical Note 5: Infrastructure Sensitivity Tests

TABLE 1.1 HEALTH CAMPUS DEVELOPMENT TRIP ASSUMPTIONS

Dev size & Specific Generated Trips units Development AM in AM out PM in PM out

74,000 sqm Hospital 923 216 183 553

5,005 sqm Restaurant 0 0 106 83

14,715 sqm Hotel 53 65 64 37

18,780 sqm Offices 281 34 28 234

85 units Residential 7 21 17 9

419 units Residential 34 96 90 46

1.8 As such, we are able to identify not only how much hospital traffic is forecast to use HCL, but also what that forecast is as a percentage of all demand to and from the non-residential parts of the development. This is summarised in Table 1.2.

1.9 As shown, around 24% of all trips to and from this specific part of the Health Campus development in the AM peak are expected to use HCL, rising to 29% in the PM peak.

1.10 The total number of trips on HCL in 2026 is forecast to be around 380-390 in each of the morning and evening peak hours.

TABLE 1.2 HEALTH CAMPUS LINK - FORECAST FLOW (2026)

Time period Direction Forecast HCL flow Specific development HCL% demand

AM Peak IN 253 1281 20%

OUT 128 326 37%

TOTAL 381 1607 24%

PM Peak IN 108 399 27%

OUT 281 917 31%

TOTAL 389 1316 29%

1.11 To try and establish ‘who’ is forecast to use HCL, the following select link plots have been taken from the SATURN model. Separate plots are presented for each of the morning and evening peaks. These plots reflect the routes that traffic to and from the development are assigned within this latest version of the highway model and taking account of general network conditions. Although overall origins and destination proportions are carried forward from previous analysis of the Health Campus proposals, we acknowledge that forecast conditions on the network in

3 Technical Note 5: Infrastructure Sensitivity Tests

2026 may influence the choice of route taken and these might not necessarily reflect the most desired route. For example, Figure 1.3 demonstrates that while almost half of all trips to the main part of the development originate from the direction of Stephensons Way, and that many are expected to route via the Health Campus Link, there is a significant split in routes with over half predicted to assign via more central routes and to approach the new Wiggenhall Road junction from the north.

FIGURE 1.3 MORNING PEAK – DISTRIBUTION OF TRIPS TO THE SITE

4 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.4 MORNING PEAK – DISTRIBUTION OF TRIPS FROM THE SITE

1.12 In the morning peak, the Health Campus Link is used predominantly to provide a connection to Stephensons Way both to and from the site.

1.13 As shown below, a very similar pattern is predicted for the PM peak.

FIGURE 1.5 EVENING PEAK – DISTRIBUTION OF TRIPS TO THE SITE

5 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.6 EVENING PEAK – DISTRIBUTION OF TRIPS FROM THE SITE

1.14 To assess which routes the traffic would re-assign to if HCL was not available, similar select plots have been produced without HCL. Figures 1.7 and 1.8 provide the results for the AM peak, with corresponding PM peak results shown in Figures 1.10 and 1.11.

FIGURE 1.7 AM PEAK – TO THE SITE – NO HEALTH CAMPUS LINK ROAD

6 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.8 AM PEAK – FROM THE SITE – NO HEALTH CAMPUS LINK ROAD

1.15 The main impact in the morning peak is naturally shown inbound towards the Health Campus where flows are highest. Between Stephensons Way and the site, we see more than 100 additional trips diverted to Eastbury Road, creating even greater stress at the Deacons Hill junction. We also see increased pressure for the route via the southern section of the Town Centre Loop Road, accessing the site via Hornets Gyratory and Wiggenhall Road.

1.16 Away from the site, there are fewer trips to divert. We see around 30 trips diverted to Eastbury Road and Aldenham Road, as an alternative to using Stephensons Way. We also see around 50m more heading north on Wiggenhall Road and through the Hornets Gyratory.

1.17 Although the model predicts negligible impact in terms of queues and delays in the AM peak as a result of not providing the Health Campus Link, it is worth noting that the junction of Eastbury Road/Deacons Hill is already identified as a junction where mitigation might be required to accommodate future LDF demand. Any further demand for this junction would need to be included in further assessment work.

1.18 With respect to the Hornets Gyratory, this is already a slow part of the network and without the link would be expected to handle over 200 more two-way trips. The model accommodates this by additional rerouting of westbound traffic from the town centre away from Vicarage Road and instead on to Whippendell Road. This re-distributional effect is demonstrated in Figure 1.7 below.

7 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.9 AM PEAK – DIFFERENCE IN DEMAND FLOWS – NO HCL

1.19 A similar comparison has been made for the PM peak. Into the site we see all the HCL trips diverted to the southern part of the Town Centre Loop Road, Hornets and Wiggenhall Road.

FIGURE 1.10 PM PEAK – TO THE SITE – NO HEALTH CAMPUS LINK ROAD

8 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.11 PM PEAK – FROM THE SITE – NO HEALTH CAMPUS LINK ROAD

1.20 Outbound from the Health Campus we see similar results as the AM peak, in that we predict rerouting via Eastbury Road and Aldenham Road. However, we also see an increase of around 150 trips northbound through Hornets Gyratory and on to Cassio Way, towards St Albans Road. Both these result in the effect of having around 80 fewer trips leaving the site via Stephensons Way.

1.21 A further peculiar result in the PM peak is that we see around 75 trips leaving the site via Lammas Road/Watford Field Road to access Lower High Street. From there, the trips continue around the Dalton Way gyratory (the right turn is not permitted) before heading off to Stephensons Way. While this might be an unlikely route in reality, it is understandable why the model might assign traffic this way, given the amount of traffic on alternative routes.

Health Campus Link Sensitivity – Conclusions 1.22 We expect to see around 380-390 two-way trips on the Health Campus Link in 2026, all travelling to and from the proposed Health Campus development. The Link is mainly used as the route between the development and Stephensons Way, although the modelling acknowledges that network conditions in 2026 will affect route choice and, particularly in the AM peak, the new link road is not always the assigned route.

1.23 The ‘no-Link’ test removes the connection between Wiggenhall Road and Dalton Way, but retains the access into the Health Campus site off Wiggenhall Road.

1.24 Although the model predicts negligible impact in terms of queues and delays in either peak as a result of not providing the Health Campus Link, it is worth noting that additional traffic would be routed either via the Eastbury Road/Deacons Hill junction or via the Town Centre and Hornets Gyratory. In particular, the junction of Eastbury Road/Deacons Hill is already identified as a junction where mitigation

9 Technical Note 5: Infrastructure Sensitivity Tests

might be required to accommodate future LDF demand. Any further demand for this junction would need to be included in further assessment work and it might reasonable to assume that the developers of the Health Campus would assist in the identification of appropriate mitigation at this location.

Colonial Way Extension

1.25 The Colonial Way Extension not only provides a connection through from Colonial Way to St Albans Road (at Penn Road), but also supports the redevelopment of Watford Junction Station by providing a new access to the new development areas from the rear of the station.

1.26 The Colonial Way Extension (CWE) sensitivity test assumes that rear access to station development will continue to be provided via Penn Road but that the new section across the railway is not constructed. Direct access to the development from the eastern part of Colonial Way will not, therefore, be possible.

1.27 There is an assumption that the total demand for the rail station and the new development can be accommodated and that there has been no limit on the number of parking spaces modelled.

1.28 With reference to Technical Note 2: Future Year Model Development, the total trips assigned to the Watford Junction Station development are repeated in Table 1.3 below.

TABLE 1.3 WATFORD JUNCTION DEVELOPMENT TRIP ASSUMPTIONS

Dev size & Specific Generated Trips units Development AM in AM out PM in PM out

1,200 dwg Residential 204 487 451 272 350 Phase 1&2 850 Phase 3&4

23,225 sqm Offices 344 40 32 287 4,645 Phase 1&2 18,580 Phase 3&4

300 bed Hotel 27 34 29 25

1.29 The total number of trips forecast to make use of the new bridge in 2026 is around 1000 two-way in the morning peak, and slightly more than 800 in the evening peak. The difference between the two peaks is partly due to the additional morning peak use of the link for access to/from the railway station, as summarised in Table 1.4 below.

10 Technical Note 5: Infrastructure Sensitivity Tests

TABLE 1.4 COLONIAL WAY EXTENSION – FORECAST FLOW (2026)

Time Direction Forecast CWE Demand to/from Station%% period flow Railway Station

AM Peak Eastbound 260 42 16%

Westbound 739 345 47%

Two-way 999 387 39%

PM Peak Eastbound 317 73 23%

Westbound 520 40 8%

Two-way 837 113 14%

1.30 As before, the following select link plots have been taken from the SATURN model to establish ‘who’ is forecast to use CWE. Separate plots are presented for each of the morning and evening peaks. Unlike HCL, Colonial Way Extension is used by general traffic and, as such, the plots show traffic patterns using the new link by direction.

FIGURE 1.12 MORNING PEAK – DISTRIBUTION OF TRIPS USING CWE - EASTBOUND

11 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.13 MORNING PEAK – DISTRIBUTION OF TRIPS USING CWE - WESTBOUND

FIGURE 1.14 EVENING PEAK – DISTRIBUTION OF TRIPS USING CWE - EASTBOUND

12 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.15 EVENING PEAK – DISTRIBUTION OF TRIPS USING CWE - WESTBOUND

1.31 Although similar distributions between the two peaks and by direction, there are subtle differences between each.

1.32 Eastbound, morning peak demand is mainly between St Albans Road (south) and the M1, but CWE also provides more direct access to Imperial Way. In the evening peak, the eastbound origins appear more localised, with fewer trips destined for the M1 but greater demand towards both Imperial Way and to the south-east side of the town, via Radlett Road.

1.33 Morning peak westbound demand is similar to eastbound only more so. Also, as discussed above, there is a significant proportion of westbound demand heading for Watford Junction railway station. In the evening peak, westbound distribution is more of a mirror of AM eastbound patterns, with the key demand between M1 Junction 5 and West Watford.

1.34 To assess which routes the traffic would re-assign to if CWE was not available, similar select plots have been produced without CWE. Figure 1.16 provides the results for the AM peak, with corresponding PM peak results shown in Figure 1.17.

13 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.16 AM PEAK – DIFFERENCE IN DEMAND FLOWS – NO CWE

FIGURE 1.17 PM PEAK – DIFFERENCE IN DEMAND FLOWS – NO CWE

1.35 In the morning peak, the difference in demand flows shows a mixed picture of both those routes that can be readily identified with the closed link, and other changes where relocated traffic has a knock on impact on those previously using affected links.

1.36 There is no surprise that we see significant reduction in demand for Colonial Way and southbound on St Albans Road to the south of the proposed link, where flows are reduced by as much as 430 trips. Equally we would expect to see corresponding increases in flow on Stephensons Way, Radlett Road, Orphanage Road and Woodford Road. Perhaps more interestingly we also see relatively large increase in demand for the Town Centre Loop, with around 250 more trips on the

14 Technical Note 5: Infrastructure Sensitivity Tests

Beechen Grove section around the north and east of the town, with increases of around 120 on Exchange Road.

1.37 The evening peak also predicts a mixed picture of direct impacts and knock-on effects. Again we expect to see reductions on Colonial Way and St Albans Road, but this time we also see northbound reductions on Clarendon Road of around 125 trips. There are increases in flow on Stephensons Way, Orphanage Road and Woodford Road, although these increases are lower than in the AM peak. Increases on the Town Centre Loop are about the same.

1.38 Differences in model delay are provided in Figures 1.18 and 1.19 for the AM and PM peaks respectively.

1.39 The most significant increases in delay in the morning peak are predicted on exit from the station pick-up/drop-off area onto Woodford Road and on approach to Orphanage Road from the southern part of Radlett Road. Each are a result of increased demand for westbound traffic using this route because CWE is not available. An extra minute’s delay on St John’s Road is also forecast.

1.40 In the evening peak, we also see increased delay, albeit a smaller increase, on exit from the station on to Woodford Road. In addition, delays are forecast to increase for those exiting Church Street Car Park onto Exchange Road , and also from the area around the Borough Council’s offices and the Leisure Centre onto Hempstead Road.

FIGURE 1.18 AM PEAK – DIFFERENCE IN MODEL DELAY – NO CWE

15 Technical Note 5: Infrastructure Sensitivity Tests

FIGURE 1.19 PM PEAK – DIFFERENCE IN MODEL DELAY – NO CWE

Colonial Way Extension Sensitivity – Conclusions 1.41 We expect to see around 1000 two-way trips in the AM peak and 800 in the PM peak on the Colonial Way Extension in 2026. A significant proportion of users in the AM peak are destined for Watford Junction railway station.

1.42 The Link offers an alternative route for a number of cross-town movements, although a connection between West Watford and Stephensons Way, and the M1, is seen in each time period. The Link is also used as a route to and from Imperial Way, without having to go via Balmoral Road.

1.43 The ‘no-Link’ test removes the connection between the Imperial Way junction and the rear access to the improved rail station parking facilities. Access to station parking is via an extension of Penn Road.

1.44 Although the model predicts reductions in demand for Colonial Way and a short section of St Albans Road in each peak as a result of not providing the Colonial Way Extension, it is worth noting that additional traffic is likely to divert to Stephensons Way, Orphanage Road and Woodford Road. Increased use of this route is seen to generate queues in both peaks for any user picking-up or dropping-off passengers at the front of the station alongside Woodford Road. In addition, the predicted increase in traffic around the Town Centre Loop is likely to create delays at uncontrolled exits from town centre car parks, an effect seen in the PM peak at the Church Street Car Park.

16

CONTROL SHEET

Project/Proposal Name Three Rivers and Watford LDF

Document Title Technical Note 5: Infrastructure Sensitivity Tests

Client Contract/Project No. Click here to enter text.

SDG Project/Proposal No. 224042/01

ISSUE HISTORY

Issue No. Date Details

1 3 November 2011 Draft 2 December 2011 Final

REVIEW

Originator Steve Oliver

Other Contributors

Review by: Print Steve Oliver

Sign

DISTRIBUTION

Client: Hertfordshire County Council

Steer Davies Gleave:

L:\Projects\224\0\42\01\Outputs\Working Notes\Technical Note 5\Draft Tech Note 5 - 03Feb12.docx

Control Sheet