Milford Sounds Sewer Pump Station Re-lining
About The Job
Wells Contracting Limited was engaged by Milford Sound Tourism Limited to carry out repair and relining of the Terminal Building Sewer Pump Station and Pump Station One at the Wastewater Plant both situated at Milford Sound.
Repairs and relining were needed because of badly eroded concrete caused by Hydrogen Sulfide gas. Wells Contracting Limited using Mastermix products of which they are approved applicators for carried out the work between 7 June 2023 and 10 July 2023. Average air temperature over this time was 6.6°C and rain fall average over this time was 39mm.
Climate control had to be done to keep within manufacturers specifications for the Mastermix products being used. This was achieved using a tent to cover the pump station from the rain and electric blower heating inside the pump station to keep to an average temperature of 18°C
Learn More About The Job
• Bypass pumping was set up from the sewer manhole in the building forecourt area and from the boat berth pumping manifold to the pump station valve pit.
• The pump station was then pumped out and all waste removed via suction tank truck.
• High pressure water blasting was carried out inside the pump station to remove all loose material and waste build up.
• After water blasting, additional time was spent with an air needle scaler to remove anything the water blaster couldn’t remove plus rust from any exposed metal.
• Large cavities were then filled with Mastermix High Strength Repair (HSR)
• A coat of Mastermix Multi-cote was applied as a primer and water-proofing layer at 2mm thickness.
• A buildup layer of Mastermix Rapid Repair was used to build up eroded areas at an average of 40-50mm.
• A topcoat of Mastermix Shield was applied in two coats over the entire inside of the pump station as a protection layer at 4-5mm thickness.
• Full reinstatement of pump station
• All Mastermix products were mixed and applied as per manufacturers specifications.
Bypass pumping was set up from the screen pit to the pump station valve pit.
• The pump station was then pumped out and all waste removed via suction tank truck.
• High pressure water blasting was carried out inside the pump station to remove all loose material and waste build up.
• After water blasting, additional time was spent with an air needle scaler to remove anything the water blaster couldn’t remove plus rust from any exposed metal.
• Leaks in the pump station around the inlet pipe and gravity pipe from pump station two were fixed using Mastermix High Strength Repair (HSR)Large cavities were then filled with Mastermix High Strength Repair (HSR)
• A coat of Mastermix Multi-cote was applied as a primer and water-proofing layer at 2mm thickness.
• A buildup layer of Mastermix Rapid Repair was used to build up eroded areas at an average of 30-40mm.
• A topcoat of Mastermix Shield was applied in two coats over the entire inside of the pump station as a protection layer at 4-5mm thickness.
• Full reinstatement of pump station
• All Mastermix products were mixed and applied as per manufacturers specifications.
Before And After Transformation
About Milford Sounds & The Job
- Milford Sound is a remote location in the Fiordland National Park. The park is part of Te Wahipounamu, a UNESCO World Heritage Site.
- Is the wettest inhabited place in New Zealand – one of the wettest in the world
- Rains on average 182 days a year
- Averages around 7,000mm of rain a year
- All waste was taken offsite.
- Relining of two pump stations – one beside Milford Sound boat terminal building and the other at Milford’s wastewater plant.
- Average air temperature while doing job was 6.6°C
- Sewerage had to be kept fully operational with no spills or affect to visitor experience while job was undertaken.
bypass pumping sewerage (hourly checks) - Kept the boat discharge pumping lines operational for duration of job (Terminal building pump station)
- Fully covered work area to mitigate rain and wind.
- Fully fenced work area to protect public.
- Used own power supply.
- Heating of pump station to keep within manufacturers specifications.
- Had to be electric heating so not to introduce any carbon monoxide into the pump stations.
- Product mixing water required heating to come within manufacturers specifications before mixing.
- Mastermix chosen as required environmentally friendly products.
About Wells Contracting
Established in July 2019, Wells Contracting Limited is based in Invercargill and managed by owner Daryl Wells, a respected Drainlayer who has worked throughout Southland and Central Otago. Daryl and his right hand man Shane Adams have worked together for over 10 years and they for a formidable team specialising in drainage and water services.
Wells Contracting Limited can install, repair and/or maintain waste water, storm water and water reticulation systems, as well as general contracting work.
The company has completed a full review and upgrade to the Milford Sound wastewater system and wastewater plant. This included replacing pumps and pipework in three major pump stations while keeping the system live; build new filtering screens at the Wastewater Plant; a major upgrade of the existing clarifier tank; upgrading pipework in the UV Plant; and ongoing maintenance of the wastewater system. All this was done by keeping the plant working for minimum disruption to the client.
They have also completed potable water, power cabling and hydroelectric water intake in Milford Sound and surrounding areas; private water and sewer connections; involved in replacing the main waterline into Invercargill city; and various works for Southland District Council and Invercargill City Council.
Their most recent project was the relining of two sewer pump stations in at Milford Sound using Mastermix products. These pump stations had badly eroded concrete caused by being exposed to hydrogen sulphide gas for a long period of time.
By working closely with clients, Daryl and his team find the right solutions for any problem and their commitment to quality is unsurpassed.
Wells Contracting Limited is fully committed to health and safety procedures, ensuring all onsite hazards are identified and both staff and onsite visitors are aware of these hazards prior to entering the site. The company completes an annual health and safety assessment through SiteWise and currently have SiteWise Gold status.
Dedicated to keeping nz green
Mastermix is a proudly New Zealand owned and operated company and is committed to developing environmentally sustainable concrete products for use in our country. We are constantly assessing and identifying any issues with our processes to find more eco-friendly and effective solutions. Recycled glass, which we use in our Shield product, was an expensive problem for the local councils who were not properly equipped to process the amount of glass.
We chose to develop a concrete solution that incorporated recyclable glass into Mastermix Shield, which utilises the hard-wearing properties of glass to form a durable topcoat that is both waterproof and acid-free.
Reliable Concrete Solutions for Repair and Maintenance
Want to talk about your next repair and shield project? We are in the business of making it very easy for you to order exactly what you need and get your concrete solutions that last.
Phone or email our friendly expert team today.
