Tunnelled Sewer connection, Enfield

Projects

Tunnelled Sewer connection, Enfield

We were delighted to carry out this double sewer connection for an existing customer of ours, albeit this one was a bit of a challenge – in more ways than one…!

Location
Enfield, London
Client
DL Toro
Value
£xx,xxx
Transport-Truck-02

Objective

Our objective was to connect 6 new properties to the public sewer in the main road running thorough Enfield, in London. The connections were for both foul and surface water, one in the middle of the road and one on the far side of the road.  

The challenges....

The sewers in the road that we had to connect to, were not particularly deep, the foul sewer being 3m deep and in the centre of the road, and the surface water being 2m deep, and on the far side of the road. The original Section 106 Approval that our customer had already arranged, had detailed new manholes to be built on both the surface water and foul sewers in the road. This would have meant a road closure lasting in excess of 2 weeks. Highways were unlikely to allow a road closure and diversion on a A-road, and for this length of time. We therefore approached Thames Water and requested the method of connection be changed to Junction Insertions, with the pipework being laid to two demarcation chambers built just inside the private shared driveway of the properties.

Thames Water agreed, and this would have shortened the work in the Highway to around 8 or 9 days, and might have allowed the works to be done under 2-way traffic lights instead. We had a meeting with Highways, but based on the width of the road, the location of both of the sewers to be connected onto, and also the depth of the excavations, it was still looking like it needed to be a road closure. But Highways weren’t keen on a road closure for this length of time, at such a busy location in London. Transport For London were also reluctant.

Highways suggested a shaft on one side of the road, and for it to be tunnelled to the other side of the road. However, existing services on the side of the road nearest the site, made a shaft in the road near-on impossible. Our only option left was to sink a shaft for tunnelling, in private property. But this meant denying the residents vehicular access for the duration of the works, which would take well in excess of one month. Our customer spoke to the neighbour, and a boundary fence was taken down between the new shared driveway and next door, enabling the residents of the new properties access via the neighbour’s driveway.

About the project

With the residents’ cars diverted and the front driveway gates locked shut, we lifted block paviours and put to one side. We excavated for the tunnelling shaft, 3m deep, and just over 2m wide in both directions. The excavation was quite wet at the bottom, around 2.5m down. We formed a concrete base at the bottom of the excavation and formed a sump, where we installed a pump that ran 24 hours per day and for the duration of the job.

 

 

We used trench sheets and heavy timbers to make the excavation safe. From here the tunnel was slowly excavated at a rate of just over 1m per day, with the top of the heading about 2m down from the road level. We found the foul pipe at the bottom of the tunnel, half way across the road, and the surface water at the top, and on the far side. The junctions were fitted and pipework laid back towards the site.

 

The tunnel was backfilled and packed with dry concrete as the pipes were laid back to the site. The tunnelling work took just under three weeks to complete. After that we excavated for and laid the small amount of pipework back into the two demarcation chambers. With the pipework all connected, the excavation was backfilled with gravel and type 1 compacted in layers, and the block paving reinstated.

Despite the initial challenges with method of connection, and then resistance from the authorities to close the road, we were able to complete these works and with pretty much no inconvenience to the general public, but just a little bit of hassle for the residents whilst the works were taking place. The nature of the works wouldn’t ordinarily have warranted a tunnelling solution, these weren’t particularly deep connections, but this was our only option if the road couldn’t be closed. 

Timeline

Time to quote for the works: Less than a week

Time taken to obtain Section 106 Licence from AW: Our customer already had this, but we had to liaise with TW to get the method of connection changed, which added another two weeks to the process 

Time taken to obtain Section 50 Licence from Highways: In excess of 2 months

Leadtime to use S50 Licence: 2 weeks – due in part to TTRO (Road Closure) 

Time taken to do the work: 5 weeks

Total time:  17 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

Sewer connection, Wicken, Northants

Projects

Sewer connection, Wicken, Northants

We were approached by a private customer, who had a Treatment Plant in his back garden, but which was not working to current regs, and who wanted connecting to the public sewer in the Highway.

Location
Wicken, Northants
Client
Private customer
Value
Circa £22k
Transport-Truck-02

Objective

Our objective was to make a connection into the public sewer, in the Highway and 35 metres away from the property down the road. We then had to lay pipework across the road, up the grass verge and into the private property, and to a point where existing foul drainage could be re-routed from the old septic tank and into the public sewer.  

About the project

Our customer already had a treatment plant in his garden, which was serving his relatively new property. However the effluent was struggling to soak away in whatever drainage system had been installed for the treatment plant. Also, under new regulations that came into effect in 2020, you are no longer permitted to install a replacement treatment plant in the event that a public sewer exists in close proximity, and there was indeed a foul sewer in the carriageway outside the property.

If you need a sewer connection doing, please contact us as early as possible, there are many reasons why the lead-time for a sewer connection can be up to a year or more. For more information click here.

We acted on behalf of our customer to facilitate the Section 106 application to Anglian Water, as we usually do. We put a basic drainage plan together, which we submitted to Anglian Water and which was accepted.

With the approval ‘in hand’, we were then able to apply for the section 50 to Highways. With the road being so narrow, it was clearly going to require a road closure. Unfortunately this adds 3 month leadtime onto the whole process, and also adds extra cost.

We started our works at the connection point, the existing manhole. This was the ‘start of the run’ prior to our new connection, but it was still well in excess of a metre deep. In our favour, our customer’s property was on a higher level, so we were easily able to get the fall. We core-drilled into the manhole, and also broke out and re-formed some of the benching in the manhole. The pipework was laid across the narrow road and into the verge, and from there it continued up the verge, still in the Highway, all the way to our customer’s property about 35 metres away.

At the boundary with the property, we installed a manhole where the new drainage run turned at near-on 90 degrees. From here we continued into private property.

The existing Treatment Plant was another 20 metres away into private property. This required us to excavate and lay pipework in block paving and in unmade ground in a paddock.

We made the connection into the existing system by tapping into the final manhole in private property, just before the existing Treatment Plant. The customer asked that we decommission the Treatment Plant by filling it with some of the excavated material. To enable us to do this, we asked that he have the Plant emptied one last time, which we arranged.

The block paving was reinstated, as was the verge and grass areas, and in less than 2 weeks our customer was now off his old Treatment Plant and onto the public sewer.

Timeline

Time to quote for the works: Less than a week

Time taken to obtain Section 106 Licence from AW: 2 weeks  

Time taken to obtain Section 50 Licence from Highways: 4 weeks

Leadtime to use S50 Licence: 12 weeks – due in part to TTRO (Road Closure) 

Time taken to do the work: 10 days

Total time:  20 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

Sewer connection, Golder’s Green, London

Projects

Sewer connection, Golder's Green, London, Case Study

We were approached by a private customer, who had been referred to us by another private customer, to undertake both a foul and surface water connection for an existing property.

Location
Golder's Green, London
Client
Private customer
Value
Circa £23k
Transport-Truck-02

Objective

Our objective was to make two new connections onto the public sewer, both foul and surface water and connect to an existing property. The connections were made in the centre of the road, and pipes laid back to the boundary with private property. We connected the new pipework into the existing sewerage system within private property which included us making some alterations to the existing system.

In addition, we lifted an existing paved area and re-laid all the slabs.

About the project

Our customer already had a connection into a neighbouring property, but required two connections to be made into the public sewers in the Highway instead. This included both the foul and surface water sewers. The surface water sewer was in the centre of the road, at a couple of metres deep. The foul was closer to the pavement, but was in excess of 3m deep.

We facilitated to Section 106 to Thames Water, which included us putting together a basic drainage drawing, which detailed where the pipework was within the property, and also how we planned to connect to the two sewers and by which method. For the surface water we were able to fit a saddle connection and for the foul we had to fit a junction insertion.

If you need a sewer connection doing, please contact us as early as possible, there are many reasons why the lead-time for a sewer connection can be up to a year or more. For more information click here.

Our Section 50 application to Highways included some legal suspensions of parking spaces, in order that we could clear cars in advance of the work taking place. With the site set up on day one, we brought our own 3.7 tonne mini digger to site, complete with breaker.

As is the condition with a Section 50 Licence, we were obliged to source all drawings for utilities that might be present within the area to be excavated. We also sprayed up where we expected services to be, having done a CAT scan of the area.

We sawcut and broke out for the pit in the road, where we would make the two connections.

We were lucky to have very few services in the road and located both the foul and surface water sewers on day one. Over the next couple of days we carefully excavated around both sewers, breaking concrete away from the surface water sewer, as is of the case.

We sheeted the excavation as we went, using trench sheets, acrows and timbers.

We made the connections onto both sewers and these were inspected and passed by the Thames Water Inspector. We then proceeded to excavate further and to lay pipes towards the pavement.

In the pavement we encountered a lot more services, including a cast iron pipe which we think was a water main, also a couple of electric cables, BT ducts, a small BT cable which we were lucky to avoid, and also some fairly shallow Cable TV ducts. We had to hand dig around all of these services, after which we continued to lay pipework, for foul and surface water, into private property.

In private property we had to remove and reinstall the demarcation manhole for the foul, which included turning it to face the new direction out towards the Highway. From this new demarcation manhole we laid plastic 110mm pipework to connect up to the clay pipework we’d laid up to the boundary.  

 

For the surface water we had to lay new 110mm plastic pipework from the downpipes on the house, to a new demarcation chamber that we installed, and from here will laid pipework up to that which we’d laid to the boundary in clay.

As part of the quote to our customer, we had included to lift and relay about 20 paving slabs which were uneven, creating a trip hazard. We re-laid these on a wet sand/cement bed, and pointed up around the two demarcation manholes.

With the excavations backfilled and compacted in the Highway, we reinstated with tarmac, and in the pavement we re-laid the large slabs that were there previously. The job took us 8 days from start to finish, including the work in private property. We finished by jet washing in private property and in the Highway, removing all signage and barriers from site, and taking our plant and machinery home for a well-earned rest!

Timeline

Time to quote for the works: Less than a week

Time taken to obtain Section 106 Licence from TW: 2 weeks  

Time taken to obtain Section 50 Licence from Highways: 4 weeks – included talks between us and Highways regards traffic management, suspended parking bays, and we also had a site meeting with the representative from Highways

Leadtime to use S50 Licence: 6 weeks 

Time taken to do the work: 8 days

Total time:  15 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

S278 Works & Sewer Connection, Kettering

Projects

S278 Works, Kettering & Sewer Connection, Case Study

We were delighted to undertake these works for longstanding customer of ours, Parrott Construction

Location
Kettering, Northants
Client
Parrott Construction
Value
£xx,xxx
commercial contracts

Objective

Our objective was to facilitate Section 278 works and an Anglian Water sewer connection, for an affordable housing development in Kettering, Northants. Our customer was Parrott Construction, a long standing customer of ours, established way back in 1958…!

About the project

The bulk of the admin work had already been done by our customer, including drawings and design, which had all been approved by Highways. But even with this process complete, we had to start the process of applying for roadspace and organising traffic management etc. With the width of the road in mind and the space we needed to carry out the works, we agreed a road closure with Northants Highways. However, as there was no footpath on the other side of the road, we had to allocate 1.2m of the road for a pedestrian walkway. We also had to apply for a Section 50 Licence, to connect to the public sewer, although the work would be carried out under the same traffic management as the S278 works.

With the road closed and the pedestrian walkway set up, we broke out and removed all of the old footpath, including the kerbs and kerb brace, in preparation for full construction of the new footpath and kerbs. 

Type 1 MOT was laid to the correct specification as required by Northants Highways, new kerbs laid and the base course laid for the new footpath.

As well as the Section 278 works, we also installed a connection to the public sewer for the new properties. This was for foul only, with the surface water having been taken care of within the site boundaries by our customer. As with all the sewer connections we undertake, we liaise with Anglian Water from start to finish including arranging all inspections and final sign-off. 

Both the base course and the 6mm topping was laid by hand, due to the nature of the works. The road closure was taken down within hours of our work having being completed, and the site cleared the next day. Our work was inspected by Highways two weeks later and passed in its entirety. The works on the site were completed by our customer within days of our own work being done, and tenants were in within a week of all work being completed. It was great to work on this exciting, local project, and for a customer with whom we have had such a great and longstanding relationship.

For any similar works or for any general groundwork enquiries, please don’t hesitate to contact us. And click here to read more of our case studies.  

Sewer connection, Golder’s Green, London

Projects

Sewer connection, Golder's Green, London, Case Study

We were approached by a private customer, who had been referred to us by another private customer, to undertake both a foul and surface water connection for an existing property.

Location
Golder's Green, London
Client
Private customer
Value
Circa £23k
Transport-Truck-02

Objective

Our objective was to make two new connections onto the public sewer, both foul and surface water and connect to an existing property. The connections were made in the centre of the road, and pipes laid back to the boundary with private property. We connected the new pipework into the existing sewerage system within private property which included us making some alterations to the existing system.

In addition, we lifted an existing paved area and re-laid all the slabs.

About the project

Our customer already had a connection into a neighbouring property, but required two connections to be made into the public sewers in the Highway instead. This included both the foul and surface water sewers. The surface water sewer was in the centre of the road, at a couple of metres deep. The foul was closer to the pavement, but was in excess of 3m deep.

We facilitated to Section 106 to Thames Water, which included us putting together a basic drainage drawing, which detailed where the pipework was within the property, and also how we planned to connect to the two sewers and by which method. For the surface water we were able to fit a saddle connection and for the foul we had to fit a junction insertion.

If you need a sewer connection doing, please contact us as early as possible, there are many reasons why the lead-time for a sewer connection can be up to a year or more. For more information click here.

Our Section 50 application to Highways included some legal suspensions of parking spaces, in order that we could clear cars in advance of the work taking place. With the site set up on day one, we brought our own 3.7 tonne mini digger to site, complete with breaker.

As is the condition with a Section 50 Licence, we were obliged to source all drawings for utilities that might be present within the area to be excavated. We also sprayed up where we expected services to be, having done a CAT scan of the area.

We sawcut and broke out for the pit in the road, where we would make the two connections.

We were lucky to have very few services in the road and located both the foul and surface water sewers on day one. Over the next couple of days we carefully excavated around both sewers, breaking concrete away from the surface water sewer, as is of the case.

We sheeted the excavation as we went, using trench sheets, acrows and timbers.

We made the connections onto both sewers and these were inspected and passed by the Thames Water Inspector. We then proceeded to excavate further and to lay pipes towards the pavement.

In the pavement we encountered a lot more services, including a cast iron pipe which we think was a water main, also a couple of electric cables, BT ducts, a small BT cable which we were lucky to avoid, and also some fairly shallow Cable TV ducts. We had to hand dig around all of these services, after which we continued to lay pipework, for foul and surface water, into private property.

In private property we had to remove and reinstall the demarcation manhole for the foul, which included turning it to face the new direction out towards the Highway. From this new demarcation manhole we laid plastic 110mm pipework to connect up to the clay pipework we’d laid up to the boundary.  

 

For the surface water we had to lay new 110mm plastic pipework from the downpipes on the house, to a new demarcation chamber that we installed, and from here will laid pipework up to that which we’d laid to the boundary in clay.

As part of the quote to our customer, we had included to lift and relay about 20 paving slabs which were uneven, creating a trip hazard. We re-laid these on a wet sand/cement bed, and pointed up around the two demarcation manholes.

With the excavations backfilled and compacted in the Highway, we reinstated with tarmac, and in the pavement we re-laid the large slabs that were there previously. The job took us 8 days from start to finish, including the work in private property. We finished by jet washing in private property and in the Highway, removing all signage and barriers from site, and taking our plant and machinery home for a well-earned rest!

Timeline

Time to quote for the works: Less than a week

Time taken to obtain Section 106 Licence from TW: 2 weeks  

Time taken to obtain Section 50 Licence from Highways: 4 weeks – included talks between us and Highways regards traffic management, suspended parking bays, and we also had a site meeting with the representative from Highways

Leadtime to use S50 Licence: 6 weeks 

Time taken to do the work: 8 days

Total time:  15 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

Sewer connection, Waddesdon

Projects

Sewer connection, Waddesdon, case study

We were approached by Fitzgerald Building Services to connect one new property to the public sewer, on the main road running through the picturesque town of Waddesdon in Buckinghamshire.

Location
Waddesdon, Buckinghamshire
Client
Fitzgerald Building Services
Value
Circa £14k
Transport-Truck-02

Objective

Our objective was to make a new connection onto the public sewer in the main road running through the town. And then to lay pipework back to the boundary where our customer had terminated his pipework and built a demarcation manhole.

About the project

On this occasion our customer already had the Section 106 approval from Thames Water which was really handy, and enabled us to go straight to Highways and apply for the Section 50 application, which we always take care of on behalf of our customer. (You cannot apply for a Section 50 before you have the Section 106)

This required us filling out the Section 50 Application Forms, supplying our accreditations, insurance documents, a traffic management plan, utilities drawings for all other services (Highways have a duty of care to ensure we know where all other utilities are before we start excavating) and various other documents. For the traffic management, we opted for 2-way traffic lights, as this was quite a busy main road.

Our S50 application was rejected initially, as the road was a HS2 diversion route at the time, and traffic lights and road closures are prohibited on HS2 diversion routes. This created a huge problem for our customer as the house was pretty much finished, and waiting for HS2 to complete in the area would have meant a delay of over a year, before he could finish the project and sell the property.

If you need a sewer connection doing, please contact us as early as possible, there are many reasons why the lead-time for a sewer connection can be up to a year or more. For more information click here.

We appealed to Highways and they eventually agreed on ‘give & take’ traffic management for this job, if we were able to keep our excavation far enough over, that we could leave 7m of road remaining outside of the works, for two lanes of traffic to be maintained. We took measurements on site, and this was indeed possible.

The Section 106 approval letter from Thames water detailed connection to the public sewer by way of Junction Insertion, which is the most common method of connection for a single house. This is simply putting a Y-Junction onto the sewer – but of course it’s not that simple with it being a live sewer! It requires us to stop the flow upstream in order that our exaction is not flooded with sewerage whilst the connection is being made. We had all manner of other utilities in our excavation where the connection was made, which is usual, including a gas main and a water main.

We knew where these were in advance as we had the utilities drawings for existing utilities, but there are always services in the Highway that are not on any drawings!

The pipework was laid from the connection point and back to the site. The majority of the pipework, for about 8 metres, was in a wide parking layby. With the connection having been made at approximately 1.4m deep, it made the pipework back to the site a bit over a metre throughout, and of course becoming shallower as we worked back to the site. The carriageway and the layby had to be backfilled and made safe before we could extend our excavation into the footpath – the road was too busy for us to ask pedestrians to cross the road and use the other footpath. In advance of reinstating the carriageway and the layby, we used a ‘footpath board’ to enable pedestrians to cross our back-filled excavation in the layby, whilst we excavated in the footpath.

As usual, we found plenty of smaller utilities in the footpath, including electric cables, BT cables and ducts, and a water service pipe, all of which we had to hand-dig underneath.

The pipework was laid up to the boundary with the private property. A demarcation manhole is always required within 1 metre of the boundary with the Highway, but this was not within our remit, and the customer had already fitted this, and left a plastic 110mm spur from the demarcation manhole to the boundary, onto which we connected our clay pipework. With all pipework complete and tested, we prepared for tarmac reinstatement. We collected base course tarmac and 10mm tarmac ourselves on our own 4-wheel grab lorry and the reinstatement was completed just over a week after we started on site.   

Timeline

Time to quote for the works: Less than a week

Time taken to obtain Section 106 Licence from AW: (Our customer already had this)

Time taken to obtain Section 50 Licence from Highways: 5 weeks – included talks between us and Highways regards traffic management

Leadtime to use S50 Licence: 5 weeks 

Time taken to do the work: Just over a week

Total time:  12 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

Sewer connection and associated utilities works, Creaton

Projects

Sewer connection and associated utilities works, Creaton, case study

We were approached by David, a friend of his recommended he contact us regarding his project whereby he required a sewer connection and various other utilities laying from his barn conversion, all the way down to the Highway, 250 metres away.

Location
Creaton, Northants
Client
Private customer
Value
circa £40k
Transport-Truck-02

Objective

Our objective was to connect to the sewer in the Highway and lay pipework to the boundary with the property. And then to lay drainage including pipework & manholes, from the boundary with the Highway, all the way to the location of the barn conversion, over 200 metres away. We also laid other services in the same trench.

About the project

.

As is usual, we took care of both the Section 106 to Anglian Water, and also the Section 50 to Highways. Our customer already had drawings for the proposed drainage in the site, but we asked for amendments to be made to include the work in the Highway. These included for the pipework to be laid across the road to the connection point in the footpath. A ‘drainage drawing’ submitted to the Water Authority for a Section 106 has to include the pipework, detailing the pipe material & size, it has to detail the size of the existing sewer we are to connect onto, and the method of connection. In this case the method of connection was ‘Junction Insertion’.

With the drainage drawing amended, we facilitated the Section 106 application to Anglian Water. This was passed within a couple of weeks, and with the Section 106 Approval Letter in hand we made the application to Highways for the Section 50 – you cannot legally apply for a Section 50 to ‘dig up the road’ before you have the Section 106 from the water authority. Highways have a duty of care to ensure we have permission to connect onto the target apparatus, in this case the public sewer. As part of our Section 50 application to Highways, we nominated ‘give and take’ traffic management, as the road was a quiet ‘dead-end’ road without much traffic. The Section 50 was approved within 3 weeks, as is usual for a simple S50 application – but beware, the application can often take much, much longer. Click here to find out more.

We had to give 3 weeks’ notice to Highways that we wished to use our Section 50 Licence. We started on the ‘other’ side of the road to the site, in the footpath, where we believed the public sewer to be. We found the pipe at 1.6m deep, and under various other services. We made the connection onto the public sewer on day 1, and this was inspected and passed by Anglian Water on day 2. With the connection made and approved, we worked our way across the road, laying 100mm clay pipes in the direction of the site. We completed the work in the road in two halves, reinstating the first half with tarmac before continuing with the second half. The work in the Highway was complete in 6 days, including all reinstatement.

We arranged with our customer to carry out the works in private property straight after the work in the Highway. The work in private property included laying 110mm plastic pipework for the foul drainage, and various manholes along the way, and also other services relating to the barn conversion. These included 125mm electric duct, 90mm BT duct, 32mm water pipe and also a spare 63mm electric duct for future use, i.e. electric gates or similar.  

We dug various trial holes and CAT-scanned the site for electric, and luckily found there to be no services in the first half of the route. There was some electric in the second half nearest the barn conversion, we marked these and also dug exploratory holes to ascertain depth of cables etc.

The electric ducts were supplied by National Grid, as is usual, and we collected them from their local depot. We dug our trench about 1.2m deep. The foul and the water pipe were laid towards the bottom, the foul in gravel surround and the water in sand surround, with warning tape to cover. The two electric ducts were laid above and also the BT, and laid in sand surround and with more warning tape to finish.

The services were all laid to one side of the farm track leading to the barn conversion, but we had two tarmac roads to cross further up, which we reinstated with tarmac afterwards. We pulled draw cords through the ducts to enable cables to be pulled through later. With the total distance of pipework being in excess of 200 metres, and with four separate rolls of 32mm water pipe being laid and joined together, we decided to fusion-weld the water pipes together so we could be sure that the joints were 100% watertight under pressure later on when the connection was done in the Highway by Anglian Water. The most common way to join water pipes together is by way of ‘compression joints’, but it is harder to know for sure that the connections are good, in advance of the pipes being live, and we wanted to have confidence that we could backfill in advance of this. 

All trenches were compacted in layers and reinstated, whether it be with grass or topsoil, or tarmac where we crossed roads further up. The ground at the top was particularly wet, and some of the foul pipe runs were in excess of 1.8m deep here. We found various land drains running through our trenches at this point as well, which made our job harder, with water pouring into our trenches as we were excavating and laying various pipes and ducts. With all of the trenchwork complete, we went back to the bottom of the track and tidied the site from start to finish, scraping the farm track as we went, and hosing and sweeping where required

Timeline

Time taken to quote for the works: Less than 1 week

Time taken to obtain Section 106 Licence from AW: 2 weeks

Time taken to obtain Section 50 Licence from Highways: 3 weeks

Leadtime to use S50 Licence: 3 weeks

Time taken to do the work: 3 weeks

 

Total time:  12 weeks

Do you need a sewer connection needs doing? Click here to enquire.

Don’t leave it too late for a sewer connection, most people do! Read our article here: How long does it take to do a sewer connection?

Click here to see more of our case studies.

Sewer Connection, Stockport

Projects

Sewer Connection Stockport, Case Study

We were approached by long-time customer of ours Fox Construction of Chapenhall in Scotland. Fox undertake full refurbishments and new construction of Shell Petrol stations throughout the UK. Their job in Turncroft Lane, Stockport required us to make both a surface water and foul connection to the public sewer.

Location
Stockport, Cheshire
Client
Fox Construction Ltd
Value
Circa £39k
Sewer Connections - Building-Site-Scene - JW Clark

Objective

Our objective was to lay surface water pipework from the site boundary of a new Shell Petrol Station in Stockport, and to connect into an existing surface water manhole in the carriageway. And then to do the same for the foul, connection into a manhole again. The surface water was 2m deep, however the foul connection was a bit more challenging, the connection into the existing foul manhole was to be made at 4.3m dig depth. The presence of a Medium Pressure Gas Man within our excavation had to be factored in as to how the works would be carried out. 

About the project

Despite these works being quite challenging in many different ways, traffic management was quite simple on this one. The two connections to the sewer were made at the back of the site, onto a quieter road, and we were therefore able to use ‘give & take’ traffic management.

However, the road was riddled with services including multiple high voltage electric ducts, large water mains, two gas mains (one of them Medium Pressure) and also two very large decommissioned steel mains, likely to have been gas & water. We also had to contend with lower voltage electric cables & BT ducts.

The surface water connection was done first, this required us to excavate in the pavement and a metre into the carriageway, where connection was made into an existing surface water manhole. The depth of this connection was 2 metres. The excavation was sheeted and a third party core-driller was brought in to core-drill the manhole. The pipework was installed, the excavation backfilled, and the manhole was ‘made good’ inside. 

The foul connection required excavation in the footpath also, and then 4 linear metres into the carriageway in the direction of the existing foul manhole. This manhole was 4.3m deep, and United Utilities (owner of the apparatus) required a soffit-to-soffit connection, as is usual for foul connections in particular. The excavation in the carriageway was extensive and required a large pit excavating 4m wide and across half of the carriageway. Within this excavation was an existing Medium Pressure Gas Main, amongst many other services. The presence of the MP Gas Main required us to consult with the owner of the apparatus, Cadent. We put proposals to Cadent which excluded use of the excavator within 1 metre of the Gas Main. Adjacent to the MP main, we had to hand dig, and then the bulk of the excavating was done with a Vacuum Excavator (Vac-Ex), which is basically a big vacuum the size of a very large lorry, see pictures below.

As the MP Gas Main would be passing through our excavation, and the supporting ground dug out from underneath it, the gas main would need to be supported from above. We put proposals to Cadent which included a 5m long steel beam, 150mm x 100mm, placed directly above the gas main. From the steel beam, we strapped the gas main at 500mm centres. Cadent approved all of our proposals and visited site to inspect our method of working, which was all satisfactory to them. 

The excavation at its deepest was 4.3m, which had to be excavated with the Vac-Ex in stages, with us inserting trench sheets, heavy timbers, and acrows as the excavation got deeper. Ordinarily a ‘trench box’ would be lowered into the ground, but with all the services we had to contend with, the excavation had to be sheeted out around and underneath the services. The deepest part of the excavation was directly under the gas main. 

With all of the trench sheeting complete, a third party core-driller was brought in and the manhole core-drilled. The pipework was installed for the foul from the site to the manhole. The manhole was very small inside, for its depth, such as they used to be, this is likely a Victorian-era manhole. As with any manhole entry though, an operative has to be lowered down on a winch, with gas tests done prior and during entry into the manhole. Should anything happen to the operative whilst down the manhole, he would be winched out as opposed to somebody going down there to rescue him. All of our operatives have confined-space training for this reason, which has to be updated and renewed regularly. We cannot undertake new sewer connections without these accreditations, and of course it’s what is needed to keep everybody safe. 

The deep excavation was filled with primary aggregate, with all excavated material having been removed from site. The excavations for both the surface water and foul sewer connection were reinstated at the same time, and the site cleared of all signage and plant & machinery etc.

This was a challenging sewer connection due to the depth of the foul in particular, and also as a result of the Medium Pressure Gas Main, exactly where we didn’t want it. But as always there is a safe method of carrying out these types of works, no matter what the depth and the difficulties involved.

It was a pleasure to have carried out this work for Fox Construction and JW Clark continue to work with Fox Construction on sites across the UK.

Timeline

Time taken to quote for the works: Less than 1 week

Time taken to obtain Section 106 Licence: 4 weeks

Time taken to obtain Section 50 Licence: 10 weeks

Leadtime to use S50 Licence: 3 weeks

Time taken to do the work: 2 weeks

Total time: 20 weeks from enquiry by Fox, to the work being completed

Do you need a sewer connection needs doing? Don’t leave it too late, most people do! Read our article here: How long does it take to do a sewer connection?

 

Stafford Sewer Connections

Projects

Stafford Sewer Connections, Case Study

We were approached by Pritpal of Dulkoo Properties, in Stafford, he had built a new house and needed a connection to the sewer, for both foul and surface water.

Location
Stafford, Staffordshire
Client
Dulkoo Properties
Value
Circa £30k
Sewer Connections - Building-Site-Scene - JW Clark

Objective

Our objective was to make a connection to the surface water connection in the Highway, at 1.5m deep and lay pipework back to the site boundary. The foul connection was a bit trickier at 3.5m deep, and from here we also laid pipework back to the site boundary.

About the project

We met with Stafford Highways to discuss traffic management for the job, and despite the works being on a 3-way junction, we agreed on 2-way traffic lights, but with signage on the side road indicating that traffic on the main road was under signal control. We located the surface water pipe on day 1, on the opposite side of the road to the site. The existing pipe was less than 1.5m deep, and the connection was made using ‘junction insertion’ method. The connection was inspected and passed by Severn Trent Water, and then from the connection point we laid pipework back to the site boundary. The STW Inspector requested that the pipework be concrete-protected, due to how shallow it was in the carriageway. With the surface water pipe laid and the excavation backfilled, we reinstated the Highway to Stafford Highways’ spec. As a Class 1 road, this required in excess of 300mm of tarmac to be laid, in three layers. 

 

The new road surface was allowed to cool overnight, and the traffic lights were switched over in the morning, and excavation was started in preparation for the foul connection. At an invert depth of over 3.5m, we expected to find the top of the 450mm foul sewer at a depth of approx. 3 metres. Due to the depth of the excavation, an extensive amount of trench sheeting and acrow props were required to enable safe entry into the excavation for our operatives. Having excavated down to 2.5m however, and having made the excavation safe, we started to encounter groundwater coming into the sides of the excavation deep down, which were unable to control with pumps. The ground was ‘silty’ and the volume of water made it impossible for us to continue. With the water content we had to deal with and the nature of the ground combined, it is not possible to use pumps to remove the water. We consulted Dewatering Services Ltd whom we have used on a number of occasions, and made plans for them to come to site to ‘dewater’ the ground. Unfortunately they were unable to come there and then, and due to the traffic-sensitive nature of the road, Highways required us to abandon the excavation, reinstate the road and remove the traffic management, which we did. 

 

Just over a week later, we set up the traffic lights all over again….! And Dewatering Services Ltd came to site. In preparation for their arrival, we had re-dug down to a depth of just over two metres, and reinstalled the trench-sheeting system. The Dewatering system included metal rods being pushed 5m into the ground, the whole system was installed in a day. 24 hours later and the excavation had been dried out, we excavated down another metre or so to get to our target depth of 3m, and installed more trench sheets and supports further down. We located the top of the 450mm concrete sewer at 3.15m down from the road level. The concrete sewer was encased in more concrete, which needed to be broken off carefully with a handheld breaker, to gain clear access to the pipe for core-drilling. We instructed a professional core-driller to core-drill into the concrete pipe. With the hole having been cored, we fixed a clay saddle onto the 450mm sewer and secured the saddle and the first clay pipe, with extra-strong and quick-setting mortar. From the connection point we continued to lay 100mm clay pipes towards the boundary. This included excavating under numerous existing services both in the carriageway and in the pavement and cycleway. 

 

The dewatering equipment was removed from site as soon as we came up to 1.5m dig depth, near to the site. The excavation was backfilled and the carriageway, pavement and cycleway all permanently reinstated.  


The project was a reasonably challenging one, due to the dig depth and the water content within the ground. But it is not unusual to encounter groundwater such as this, especially at this depth, and we have plenty of expertise in this area, and often at much deeper depths as well. It was a pleasure to have carried out this work for Pritpal, and we wish him every success with this project and any others we are able to help with going forward. 

Timeline

Time taken to quote for the works: 1 week

Time taken to obtain Section 106 Licence: Our customer already had this

Time taken to obtain Section 50 Licence: The licence only took a few weeks to obtain…. 

Leadtime to use S50 Licence: …….but we had to wait in excess of 3 months before the work could be started, due to other works being undertaken in the area, a road closure around the corner. Highways will not often permit two jobs to run concurrently within a certain radius, and we are never able to carry out works in what is a ‘diversion route’ for another road closure.

Time taken to do the work: 3.5 weeks including us having to go away for a week and then come back with Dewatering Services

Total time: 4.5 months including the delay in being able to use our Section 50 licence, due to other roadworks being carried out in the vicinity. 

Do you need a sewer connection needs doing? Don’t leave it too late, most people do! Read our article here: How long does it take to do a sewer connection?

Woodcote Sewer Connection

Projects

Woodcote Sewer Connection, Case Study

Location
Woodcote, South Oxfordshire
Client
Greenham Construction Ltd
Value
Circa £14k
Sewer Connections - Building-Site-Scene - JW Clark

Objective

We were delighted to be approached by Greenham Construction from Newbury, a first-time customer. They were building a high-end property in Woodcote, South Oxfordshire, and needed the property connecting to the public sewer.

About the project

The property being built was a long way from the Highway, and the levels didn’t work with getting into the public sewer by gravity. Therefore a pump system was installed within the site, an MDPE pipe was laid in the track leading to the site, and a ‘break chamber’ installed a few metres from the boundary with the Highway. This was all done by the customer, with us instructed to do the gravity work in the Highway. 

The customer already had the Section 106 approval, which detailed connection onto the public sewer by way of new manhole construction. We put a quote together for our customer based on information provided to us, the Thames Water Asset Drawing, and also what we were able to see on Google Earth and Google Street View.

The customer was happy with our quote in principal, so we did a site visit whereby we lifted manholes to check pipe depths etc. The road was fairly narrow for the work that was required and we were concerned that a road closure would be required, which would have added a few thousand pounds to the cost. Ordinarily we need to leave 3.5m carriageway width outside of our works, but we were only able to leave 3m. However Oxfordshire Highways were happy with 3m available carriageway, so the works were able to proceed using ‘give & take’ traffic management, which is normally the cheapest method. 

We started on site two months after our initial contact with the customer. Upon locating the existing sewer we found the pipe material to be asbestos, which are still quite common. Our operatives are asbestos-trained for this reason, and we took all necessary precautions to ensure that the existing pipe in the road was cut safely and as per H&S regulations relating to asbestos.We constructed the new manhole on top of the existing sewer using concrete 1.2m diameter sections, finished with a ‘biscuit’ and a 150mm D400 manhole cover. 

We then excavated for and laid the pipework from the new manhole, to the boundary with the customer’s property. The pipework we laid was a bit under 2m deep, and consisted of a few metres in the carriageway and the remainder in the tarmac footpath. As this was a quiet road, we closed the footpath and diverted pedestrians onto the other side of the road whilst the works were carried out. With the pipes laid, trenches backfilled and reinstated, the Highway was reopened and the site cleared 6 days after we started. 

It was a pleasure to carry out these works for Greenham Construction and we look forward to working with them again in the future.

Timeline

Timeline

Time taken to quote for the works: 1 week

Time taken to obtain Section 106 Licence: (Customer already had this)

Time taken to obtain Section 50 Licence: 3 weeks

Leadtime to use Licence: 4 weeks

Time taken to do the work: 1 week

Total time: 9 weeks

Do you need a sewer connection needs doing? Don’t leave it too late, most people do! Read our article here: How long does it take to do a sewer connection?