Ornamental Canal

IMG_7193A couple of weeks ago I met with Michael and Matthew of Tower Hamlets’ Clean & Green team to conduct a walkabout of Wapping’s Ornamental Canal as I had received a few complaints about its maintenance from residents. On that walkabout I reported graffiti, greenery that needed trimming back and complaints about the bollard lighting not working. I met Wapping wader, Chris, and his team mate (Paul, I think?) who clean the canal daily of Canadian pond weed and other detritus. I also had the chance to meet the Wapping swan family (Chris calls the mother Gertrude!) who were in the middle of giving the cygnets a flying lesson.

I asked Michael for a written account of what the council does to maintain the canal as a follow-up to our meeting so that residents can understand why to expect from Tower Hamlets and what progress is being made on issues like the bollard lighting. I paste below the information he has provided. This includes a full account of what happened to the pumps on the canal after they broke, and an outline of the cleaning contract in place for maintenance of the canal.

Canadian Pond Weed

The removal of Canadian Pond Weed from the canal is an ongoing process, which is carried out by our Service Provider Bow Maintenance on a regular basis. This particular type of pond weed is very invasive in nature as the plant spreads through fragmentation.

The Council will continue to monitor the canal and remove the pond weed on a regular basis in order to keep this under control. Once the temperature drops as winter sets in, the weed tends to die off.

Pumps

A survey was carried out by our surveyors department to ascertain if the disconnected pumps at Waterman Way could be reinstated. The survey showed that the pumps no longer exist and the Council do not currently have the funding to introduce new pumps to this section of the canal. (Full details below)

Lighting 

The council’s Street Lighting department have reviewed the bollards alongside the Wapping Ornamental Canal and are in the process of trying to secure funding for the reinstatement of the disconnected bollards.

Signage

Signage has been erected along the tow paths of the canal to encourage cyclist to slow down and we have also reported this issue to the partnership task force to ask for regular patrols in this regard to assist in raising cyclist awareness.

Cleaning Contract for Canal

D1.10.1       AQC3: Clean Canal Areas Daily From Land                               (PRO)

Remove all floating and suspended litter, occasional leaf* or plant litter, and larger sunken debris such as road cone, shopping trolley or car tyre. All waste collected must be placed directly into sacks, barrows or vehicle and disposed of. Waste must not be placed on the banks or stored on site. The Contractor must include in the rates to clear pump intake and overflow grilles and outlets, where litter and leaves tend to collect. *Additional rates apply to the clearance of seasonal (autumn/winter) leaf fall.

D1.10.2       As part of this operation the contractor will be expected to remove any dead animals including fish, waterfowl, small mammals and the like. The Contractor is also required to report the occurrence of dead, sick or injured animals to the Client for further remedial action as appropriate.

D1.10.3       AQC4: Enter & Clean Canal                                                (PRO)

Remove floating and suspended litter including occasional leaf and plant litter, and larger sunken debris (e.g., road cone, shopping trolley, car tyre) from water areas inaccessible from land. All waste collected must be placed directly into sacks, barrows or vehicle and disposed of. Waste must not be placed on the banks or stored on site. The Contractor must include in the rates to clear pump intake grilles and outlets where litter and leaves tend to collect.

As part of this operation the contractor will be expected to remove any dead animals including fish, waterfowl, small mammals and the like. The Contractor is also required to report the occurrence of dead, sick or injured animals to the Client for further remedial action as appropriate.

D1.10.4       AQL2: Autumn/Winter Leaf Removal                               (PRO)

The Contractor will price a rate for leaf removal during the Autumn/Winter period. This rate will be applied as a plus rate to be applied in addition to the rates for ‘normal’ cleaning (AQL1; AQC2; AQC3 & AQC4) for the specified period.

D1.11          WATER QUALITY

D1.11.1       General

The Contractor must report to the AO any significant changes in the condition of the water feature especially with regard to correct water-flow, damage or deterioration of structures, algae/vascular plant growths, water condition, and the presence or build up of sunken foliage, debris, silt and contaminants.

D1.11.2       Any instruments, materials or testing equipment required for the execution of the work must be supplied by the Contractor and allowed for within the tendered rates.

D1.11.3       All instruments must be correctly calibrated and used in accordance with the manufacturer’s recommendations.  Calibration of such instruments must be included in the Contractor’s tendered rates.

D1.11.4       Water sampling and analysis must be in accordance with the mandatory and guidelines values set out in the Bathing Water Quality Regulations, Statutory Instructions SI 1991 No. 1597 and European Community Directive 76/160/EEC.

D1.11.5       Current monitoring and sampling locations are listed below; however these may be deleted or added to during the contract period.

  • Shadwell Basin:- Off Pontoons (used by water sports) N.E. of Dock Centre
  • Ornamental Weirs:- Centre of lowest section of weirs
  • Tobacco Dock:- from steps midway along north side
  • Western Dock Canal:- Off steps midway along north side of southern branch.

History of the Pumps

The ornamental canal is serviced by a main pump in a borehole over 70 metres deep. At the other end of the canal system is an old pump system (pump B). This was taken out of service prior to the Council taking responsibility for management of the waterway in the 1990s.

The main pump replaced the need for pump B.

In December 2012 the main pump was not working and had been defective for two months.

In February 2013 the Council carried out a deep clean of the canal. Also in February the Council referred the pump fault to its in-house consultants, the Building, Architectural and Technical Services Team (Technical Services). It asked why the water in the canal was not flowing. Technical Services investigated the issue and quickly identified the pump should be removed and inspected.

Because of the depth and position of the pump this could only be done by a specialist contractor. One UK company was able to do the work. Technical Services progressed the case with the Council through April. The Council agreed to fund the work and the pump was removed in May. On inspection they found some parts were damaged and a pipe was split. The Council replaced these during June. An additional part was required to stabilise the pump. The Council agreed funding in July and Technical Services ordered the part.

In July and early August the Council cleared algae growth from the canal. This took place over five weeks. Towards the end of July the Council received complaints about the broken pump which had stopped water flowing, and it was asked why pump B could not be reinstated. The Council said it would investigate if pump B could be used. A Surveyor from Technical Services visited the site and noted the pumps had been removed along with cables, control panels and fuses. He noted that given the size of the pumps if the Council replaced them they would be very noisy and cause a lot of vibration. The report was given to the Council and considered. The Council decided it was not a viable option.

In August Technical Services received the parts for the pump. They were fitted and the pump was working again by 20 August. Officers carried out an ad-hoc inspection of the canal on 15 September and found no cleaning issues. They alsosubsequently went to the canal with the Environmental Agency and took a watersample. They tested it and results showed it was safe with no risk to wildlife. The pump would cause sediment in the water to rise and temporarily change the colour but was harmless. It also confirmed water tests showed the canal was safe.

In February and March 2014 the contractors carried out an eight week programme clearing sunken leaves and debris from the bottom of the canal. In March the pump stopped working again. The Council asked Technical Services to carry out further investigations. It advised the Council that a specialist contractor would need to remove the pump and the Council agreed the works. These were carried out in March. Technical Services sent the pump to its manufacturer for inspection.

It reported back at the end of the month stating the pump and fittings were coated in iron oxide. This had stopped the pump closing correctly and caused damage to a power cable in the borehole. That resulted in the motor burning out. Technical

Services got a quote for the remedial works. The Council then had to agree the costs and how to proceed. This was done by mid April and Technical Services ordered the repairs. There was a minimum three week delivery time for the new motor. The contractor completed the repairs by 22 May and the pump has been operational since.

In May algae growth had increased in the canal. The Council agreed that additional clearance was needed because of the lack of water flow caused by the broken pump. It placed an order for work to clear the growth within the next four weeks.

The Council’s canal cleaning contract requires its contractor to clean the canal from the land four times a week. Operatives have to remove floating litter and debris. In addition on two other days operatives enter the water to remove larger sunken debris and harder to reach surface waste. There is an annual deep clean of the canal to remove leaf fall. This usually takes place around February. The Council can carry out further ad-hoc cleaning when required. For example, if the pump is not working algae growth will increase in warm weather. The Council will then clear the algae if it considers it unacceptable.

Operatives complete a worksheet when they clean the canal to verify work was done each day. This is passed onto the Council. The Council’s Green Team also carry out inspections of the canal walkways and water surface to check operatives are working correctly. The Green Team complete monitoring sheets each time they visit and log any issues. If an officer does spot a problem with an operative or work not properly carried out it is immediately raised with the contractor.

Technical Services are in-house consultants for the Council. This means they cannot instigate work on behalf of the Council without first obtaining the Council’s consent. The usual process would be a Council department contacts Technical Services for advice. Technical Services then investigate the issue and advise the Council about options and costs. If the Council agree on recommendations then Technical Services can commission the work. It would need to go back to the Council for consent if any additional works were required during the process.

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