Project Description

Crummock were appointed by Midlothian Council to carry out a major public realm streetscape facelift to the High Street in Dalkeith: the busiest High Street in the county.  The road was realigned making it narrower to discourage roadside parking, laybys were provided to allow short term parking and disabled parking, and the junctions at either end realigned to aid traffic flows.

 Carriageway kerbing was of natural whin stone and on street parking in Portuguese granite; footpaths were constructed in natural stone Yorkstone paving.  The laybys were of sett construction and the focal point of the High Street, a new zebra crossing was constructed in three colours of Portuguese setts.  Crummock provided in-house design services to Midlothian Council regarding the alignment and levels for the layout and the Council’s landscape architect specified the materials that were to be used in specific locations.

Scope of Works

600m3 excavation, sub-base and bituminous surfacing (with clear-coated granite chippings) to 1,600m2 carriageways, 300m2 new Portuguese granite setts to laybys laid using SAMCO 88 grouting system, 600m new Scottish whinstone kerbs, 1,800m2 new natural Yorkstone paving laid using SAMCO 88 grouting system, Belisha beacons, road signs and poles and stainless steel bollards.  Furniture including seats, litter bins and cantilever bus shelter, gully and heavy duty channel drain installations with associated outfall drainage, pedestrian guard rails, street lighting on existing buildings or new poles, traffic lights and associated ductwork and chambers, beach cobble pedestrian deterrent paving and road markings.

Challenges

Discussions were held with all the shop-keepers regarding the sequence of works required to maintain access to their premises at all times and arrangement for delivery vehicles to gain access through the works.  Programme overrun was a major concern and a risk register was compiled so that individual elements could be considered in detail to eliminate the potential for delays.  Underground services are always a likely cause for delay and after meeting the authorities’ representatives on site, trial holes were carried out at an early stage to clarify depths and positions so that any amendments or additional work could be dealt with without effecting the completion date.

The existing carriageway depth was also a concern as some areas required planing in excess of 120mm depth in order to replace a consistent 100mm throughout the job as specified.  Again trial holes were carried out and we established the existing carriageway construction in the ‘risk’ areas.  Some had to be fully reconstructed but since we knew this early in the project, it could be incorporated into the programme without delays to the overall works.

The potential for ponding was considered at design stage and the controlling factor governing the levels was the shop doorways and it was often difficult to get adequate gradients in accordance with the British Standards.  The horizontal alignment was positioned to give us adequate crossfalls but we could not always achieve longitudinal falls to the gullies.  We agreed with Midlothian council that in instances where we could not achieve 1:120 we would utilise heavy duty channel drains and tried our best to position these at the kerbside of the parking bays.

Traffic risks were minimised through the road closure and we agreed specific times with shopkeepers when they would have delivery lorries on site.  These lorries were directed into position by trained Crummock banksmen.  Pedestrians had to have access to the shops at all times and this was achieved by providing barriered walkways through the works and carrying out work directly at doorways while shops were closed.

Regular progress meetings were held by Crummock on site to monitor the programme and resolve and minor issues as they arose.  The programme period of 16 weeks had to be met due to the council being unable to continue the road closure beyond the date communicated to all proprietors on the high street.  Despite the extremely high level of quality required to both natural stone setts and paving we completed the works on the date planned with the council being delighted that this date was achieved.

The sum of money agreed prior to commencement included a reasonable contingency and this was expected to be spent by extending the works where we could.  We managed to create additional on-street parking with natural stone setts and a revised junction layout at the East end to accommodate an existing pedestrian crossing which was over and above the work scope prior to starting on site.

Innovation

Several innovation ideas were approved for adoption on this contract.  Crummock proposed the use of black and very light coloured granite setts to form the zebra crossing which has worked exceptionally well.  We also proposed the use of the Samco 88 system for laying the setts on, which has performed well as expected, with the heavy loadings it endures. Crummock cored the natural stone slabs to install the bollards producing a very neat, attractive finish.

As an indication of innovation in our service delivery, from the beginning of 2013, Crummock introduced a process with Midlothian Council to seek feedback from them on completion of works.  The Contractor Scorecard enables the Council to rate Crummock against over twelve criteria including for example, Traffic/Pedestrian Management, Surfacing Quality and Site Safety.  This feedback is important to Crummock as it enables us to improve the service we offer.  This process has now been introduced to all our clients.