Baffle Curtains

Baffle Curtains

Permathene baffle and silt curtains are manufactured in our NZ factory

Baffle & Silt Curtains

  • Waste water treatment lagoons
  • Turbidity barriers
  • Debris curtains
  • Silt curtains

Baffle curtains are used in waste water treatment reservoirs to improve the operating efficiency of WWTP systems. Baffle curtains minimise short circulating of water in the reservoir, increasing the retention time and thus optimising the reservoirs volume.

Permathene baffle curtains are fabricated in our Auckland New Zealand factory as standard 30m long interlocking units depending upon the total curtain length required.


Below is a partial list of completed works including silt curtains, turbidity barriers, baffle curtains.

  • Lagoon Barrier, Beachlands-Maraetai, Manukau City, New Zealand. Contract Completion September 2000. Contract’s Scope: 60 m long lagoon barrier fabricated from 1 mm Permaliner (Flexible Polyethylene) was installed into existing lagoon to separate it into two different biological process sections.
  • STP Suspended Curtains, Waste Water Treatment Plant, Te Awamutu, New zealand. Contract Completion August 2002. Contract’s Scope: One 65 m long 4.5 m deep baffle with 110 mm Ø floatation was installed along the center line of the pond, with 5 short 13.5 m long 4.5 m deep curtains attached perpendicular to it. Total system’s length was 132.5 m. The curtains were fabricated from Permaliner 1000 (1 mm).
  • Silt Control Curtain – Marine construction, Waiheke Island, Auckland, New Zealand. Contract Completion August 2004. Contract’s Scope: This was one of the first projects in New Zealand where a dedicated floating silt screen had actually been specified. 180 m long 4 m deep screen had 300 mm buoyancy element sealed in a PVC sleeve. Silt control skirt was fabricated from monofilament woven geotextile, complying with flow ration and opening size specified for the project.
  • Turbidity Barrier, Waikuku Beach STP, Waimakariri District, South Island, New Zealand. Contract Completion September 2005. Contract’s Scope: Two 40 m long, 1.5 m deep baffles (80 m total) were fabricated from Permaliner 750. 150 mm marine grade polystyrene was weld-sealed inside buoyancy tube, fabricated from FPP. The material specified for the lining of this pond was 1.5 mm Smooth HDPE geomembrane. A total of 4,446 m² was used on the job, and the project was completed in 6 days. The 7 m wide panels were fusion welded together on site, and all welds and seams were tested by destructive methods.
  • Turbidity Barrier, Baffle Curtain, Cromwell WWTP, Cromwell, Otago, New Zealand. Contract Completion November 2008. Contract’s Scope: A single 100 m long, 1.3 m deep baffle curtain, fabricated from Permaliner 750 was fabricated and installed at Cromwell WWTP. The baffle had 150 mm floating element, made from marine grade polystyrene, weld-sealed inside low density polyethylene tube and inserted in weld-sealed buoyancy element, fabricated from Permaliner 750. Cross-anchors (side anchors) installed from both sides of the baffle curtains every 20 m.
  • Turbidity Barrier, Baffle Curtain, Wallan STP, Victoria, Australia. Contract Completion November 2008. Contract’s Scope: supply and installation of three 90 m long 4 m deep baffle curtains (total of 270 m), fabricated from Permaliner 1000 (1 mm FPP).
  • Turbidity Barrier, Baffle Curtain, Appin West, NSW, Australia. Contract Completion March 2009. Contract’s Scope: Supply single 30 m long 2.6 m deep baffle curtain, fabricated from Permaliner 1000 (FPP 1 mm).
  • Turbidity Barrier, Baffle Curtain, Kaitaia WWTP. Contract Completion November 2009. Contract’s Scope: 642 m of 1.7 m deep baffle curtains. 8 baffle curtains were fabricated and installed in 3 ponds. Baffle’s individual lengths were 126 (three baffles), 77 m (two baffles), 60 m (One), 20 m stub baffle curtains (Two). The baffles were fabricated from Permaliner 750. Floating elements were completed from 150 mm marine grade polystyrene logs, sealed inside low density PE tube, and then inside 750 FPP buoyancy elements. This baffle curtain system was fabricated with double ballast system. Heavy 16 mm galvanized chain (5.5 kg/m) was placed in pre-welded seam 1 m below surface, and then 13 mm chain (4.4 kg/m) along the skirt’s low part. Additional ballast was required due to complex wind environment of the WWTP location, with winds reaching up to 100 km/h speed at times. The baffles were installed with cross-anchors at 15 m intervals. The second stage of the project was completed in time and at the projected cost.
  • Matamata WWTP Upgrade, Matamata, Waikato, New Zealand. Contract Completion October 2011. Contract’s Scope: Four baffle curtains 895m long total were installed in two ponds for an increased flow path throughout.
  • Iluka Resources , South Australia. Fabrication Completion January 2014. Contract’s Scope: 3 baffle curtains 18m each were supplied for installation in a settling pond at a mining plant in order to allow floating precipitate to settle before reaching the overflow pipe.
  • Gippsland WWTP Upgrade, Victoria, Australia. Fabrication Completion July 2014. Contract’s Scope: A 350m long baffle curtain was supplied for installation at a WWTP plant.
  • Stormwater Retention Bunker Baffles, NZFS Training Facility, Eastgate, Rotorua, New Zealand. Contract Completion October 2005. Contract’s Scope: Five baffles, fabricated from FPP Permaliner 750, 6.5 m long and 2.2 m deep each (32.5 m total) were fabricated and installed in New Zealand Fire Services Training Facilities in Eastgate, Rotorua for separation of suspended solids and hydrocarbons from stromwater runoff.

For further information or quotation please contact Permathene New Zealand