This is an HTML version of an attachment to the Freedom of Information request 'EIR: Warehouses Maple Cross (21/0573/FUL) Junction Improvements & Costings'.

From:
To:
MapleCrossandWestHyde ResidentsAssociation
Cc:
Phil Williams; Ralph Sangster
Subject:
RE: 21/0573/FUL - Maple Cross Development Site
Date:
08 April 2021 18:12:00
Attachments:
Good afternoon 
Many thanks for your email in respect of the above planning application. I have been dealing
with the consultee responses on behalf of Hertfordshire County Council (HCC) as Highway
Authority (HA) and therefore I will respond to you each of your points raised below.
1. HS2
The Transport Assessment (TA), which has been submitted by the applicant as part of the
application, takes into consideration construction traffic movements associated with HS2 and
the figures are included in the committed development traffic flows, which are then used to
model the capacity of nearby junctions.   HCC’s team liaising with HS2’s Project Team has been
contacted to see what can done about enforcement of Construction Route Plans in respect of
HS2.
2. Permitted Hotel Development
HCC as HA has requested a trip generation / vehicle number assessment to be carried out for the
permitted hotel in additional to updated modelling as to the capacity of the proposed signalised
junction (taking into consideration the proposed development, the permitted hotel and other
committed developments in the area).  A copy of this request should be on Three Rivers District
Council’s (TRDC) planning portal online for the application.
3. Thames Water Site
I have asked TRDC to investigate whether or not there has been a material change to the Thames
Water site that may account for the apparent increase in the number of trips.  I believe that
Thames Water would be able to increase the number of vehicles to and from their site without
additional planning permission (although this would be something TRDC can confirm).
Nevertheless any additional use of the Thames Water site would not be a reasonable justification
to recommend refusal for the application site from a highways perspective, particularly as
Thames Water are using a principle A road and then a private access road to access their site.
4. The Maple Lodge site comprises of Bulk Transfer, a car Repair/Maintenance area, and planning
permission has been sought from A1 Grab Hire, Concrete Works, etc.
The submitted TA and the capacity of the surrounding highway junctions takes into
consideration any trip generation from committed developments including HS2 and the Reach
Free School in addition to existing baseline traffic data including that on the private access road. 
In relation to the concrete works site and car repair / maintenance site, I responded to the two
retrospective planning applications (ref. 20/2831/RSP and  20/2827/RSP) stating that the HA
would only be able to assess the acceptability of these uses subject to the submission of an
appropriate Transport Statement / Transport Assessment taking into consideration trip
generation / distribution to and from these sites.  As these applications are retrospective, some

of the existing recorded trips on the private access road would most likely be from these uses or
historical uses of these sites (and would feed into the baseline traffic data used in the current TA
for the development site). 
 
According to TRDC’s planning portal, application 20/2831/RSP (hanger building for car
maintenance) has been withdrawn whilst application 20/2827/RSP (concrete mixing facility) has
been refused planning permission.
 
5. M25 - Traffic Distribution / Directional Flow
In respect of the flow of traffic to and from the site, HCC as HA has not assumed that all traffic
would access via the M25.  The submitted TA takes into consideration that some development
traffic would access the site via the A412 to and from the south and the junction modelling
included in the TA reflects this.  The traffic flows in the TA show between 23% and 27% of
development traffic would turn left in the peak hours when exiting onto the A412 (i.e. the
direction of Maple Cross and not the M25). 
 
This is considered to be reasonable when taking into consideration the close proximity of the site
to the M25.  Nevertheless a LinSig model has been used to assess the performance of the
existing signalised Chalfont Road / Denham Way / Maple Lodge Close junction and the results in
the submitted TA (sections 7.22 to 7.27) show that the junction works within capacity and the
proposals would not have demonstrable impact on the functioning of this junction.
 
Furthermore the proposed development has to be reviewed by the Highway Authority in the
context of the National Planning Policy Framework, which states that: “Development should only
be prevented or refused on highways grounds if there would be an unacceptable impact on
highway safety, or the residual cumulative impacts on the road network would be severe”. The
site is an allocated employment site in TRDC’s Local Plan and the A412 is classified as a main
distributor A road which forms part of the principle A road network. Therefore the number of
additional trips from the application site itself onto the A road would not be considered to be
severe in this context.  It is acknowledged that the capacity of the proposed signalisation
junction itself is being reviewed taking into the consideration the hotel development (as
referenced earlier).
 
6. Maple Lodge Close
I have included the recommended condition / further information in relation to how
development vehicles could be prevented from using Maple Lodge Close in response to concerns
raised by local residents.  Nevertheless Maple Lodge Close and the “northern” development
access road are private roads and therefore HCC as HA would not have powers to enforce any
restrictions if they were proposed and I consider that it would not be reasonable to recommend
refusal for the overall proposals based solely on this.   It could also be argued that there would
not be any benefit for development vehicles to access the site via Maple Lodge Close when
taking into consideration that the northern access road is a more appropriate and covenient
access route, particularly for HGVs.
 
TRDC (as the Local Planning Authority) would be able to confirm whether or not they would
deem it a reasonable and necessary requirement (i.e. to restrict development traffic accessing
via Maple Lodge Close) that meets all the planning tests (HCC are afterall a consultee
recommending conditions / further information to promote and encourage good development





in the context of the surroundings).
 
I trust the above will be of assistance to you.
 
Kind regards
 
 
Senior Development Officer | Highways Development
Management 
Hertfordshire County Council 
County Hall, Pegs Lane, Hertford, SG13 8DE, Postal Point:
CHN115
E: 
@hertfordshire.gov.uk
 
 
-----Original Message-----
From: MapleCrossandWestHyde ResidentsAssociation <xxxxxxxxxxxxxxxxxxxxxxx@xxxxx.xxx> 
Sent: 05 April 2021 18:08
To: 
@hertfordshire.gov.uk>
Cc: Phil Williams <xxxx.xxxxxxxx@xxxxxxxxxxx.xxx.xx>; Ralph Sangster
<xxxxx.xxxxxxxx@xxxxxxxxxxxxx.xxx.xx>
Subject: 21/0573/FUL
 
Dear 
,
 
I have read your submission regarding the aforementioned development and would ask you to
kindly clarify the following, with a degree of urgency as I will have to meet the Planning
Departments deadline.  
 
The following I believe to be of significance since the last traffic count and will directly affect the
flow of traffic both along Thames Water’s Access Road and the A412.
 
1.   Whilst HS2’s traffic plan no doubt suggests that their vehicles will use the slip onto the M25,
this has been found to be highly inaccurate as reported by residents who live and travel along
the A412.
Can you confirm the numbers of vehicles that you have taken into account for the proposal?
 
2.  The hotel/conference centre/gym has 375 parking bays, this will create multiple journeys
throughout the day and of course hotel bedrooms are more likely to create journeys during peak
times.
Can you confirm what vehicle numbers you have taken into account for the proposal?
 
3.  Are you aware that Thames Water traffic now amounts (our traffic count) to approximately
200 vehicle trips per day plus staff vehicles, instead of circa 16?
Can you confirm what vehicle trip numbers you have noted?
 

4.  The Maple Lodge site comprises of Bulk Transfer, a car Repair/Maintenance area, and
planning permission has been sought from A1 Grab Hire, Concrete Works, etc.
What numbers of vehicles have been taken into account for this area?   There are
 
5.  What assumptions have been made about overflow from the M25?  How often is it presumed
that the M25 will have heavy traffic and people will divert through MX?  Even in lockdown
residents have experienced frequent problems.
 
Meantime residents are very grateful that you have recognised the perilous position we would
have found ourselves in if you had not put the Condition in regarding Maple Lodge Close.
 
Look forward to your response - thanks in advance.
 
Regards,