P&P Plastics pty Ltd^

Sealmac Dam Lining System

This economical easy to apply dam lining system is the answer to all your water retaining requirements. Constructed using Sealmac impregnated with 3 coats of a mineral filled latex emulsion sealing compound, it provides a robust, highly elastic bitumen coating that is non-toxic and impervious to water.

It can be used to line new or existing water retaining structures including dam irrigation dams, oxidation ponds, water features, concrete reservoirs and canals.

Where it is used

  • Earth irrigation dams
  • Concrete Reservoirs
  • Oxidation and maturation ponds
  • Mining and industrial waste dams
  • Concrete and earth canals
  • Animal drinking troughs
  • Aquaculture ponds
  • Flat Roofs
  • Water features and decorative fishponds
  • Raw water storage dams

Benefits of the System:

  • Low Cost
  • Robust, high puncture resistance
  • Long Life expectancy
  • No tainting or toxicity imparted to water
  • Easy, Effective, Flexible, mouldable around any features
  • Install by hand using brooms
  • Employment of unskilled labour
  • Applied at ambient temperatures
  • No expensive plant required
  • Simple control procedures to ensure quality
  • Not dangerously slippery when wet
  • Very easy to maintain and/or repair
  • High resistance to effluents, acids & UV.
  • Acid resistance: unaffected by 30% sulphuric acid at 25°C
  • UV resistance: greater than 500 hrs in SABS “weatherometer”.

Installation Guidelines


  • Shape and compact earth surface.
  • Remove any vegetation, stones, sharp objects etc.
  • In areas of a high water table install a sub-surface drainage network
  • Sprinkle a granular slow-release herbicide over entire surface.
  • Excavate 300 x 300mm anchor trench around dam perimeter.
  • Place Sealmac starting with the end of a roll in anchor trench at midpoint of the embankment. Unroll to opposite trench, allowing Sealmac to drape loosely over site.
  • Continue Sealmac installation overlapping joints by 200-250mm. Remove any creases at joint intervals.


  • Seal joints by applying and undiluted heavy coat of sealing compound to the lower overlap.
  • Immediately press down upper overlap and wait to dry. After all joints have been done do second undiluted application over the whole joint.


  • First Coat: Impregnate Sealmac with sealing compound (diluted 50/50 with water) at a rate of 1.6ltr/m2. Allow approximately 6-8hours to dry.
  • Second Coat: Apply undiluted sealing compound at 1ltr/m2 and allow to 6-8 hours to dry.
  • Final Coat: Repeat as for second coat and allow to cure for 72 hours before filling with water.

A layer of washed river gravel can be applied to the wet surface at this stage to achieve a natural stone finish.

Clean tools with water while still wet or paraffin if dry.

Although tested to 15m head a maximum depth of 5mtr is recommended. Embankment slopes should exceed 1:2.


Nonwoven continuous filament double needle punched polyester


1.4mm under 2kPa

Tensile Strength:

8 kN minimum


Greater than 50%

Penetration Load

1.5 Kn

Bitumen Retention:

1.4 ltr / m2

Roll Size

3.5mtr x 150mtr