DURALINER EFFLUENT PONDLINERS & DAMLINERS A pond system for retaining effluent and runoff is a popular and relatively low cost way of catching, storing and treating effluent from farms, industrial and horticultural business. Either one main pond is typically used or there may be a series of ponds that spill and “settle” into each other and can assist with water or effluent treatment as the solids settle out in each pond and the waste water becomes less toxic of chemicals, solid waste etc. An effluent pond can also assist with controlling the direct run-off of waste water or dairy farm washdown water into existing drains and streams which is becoming an ever more highlighted issue with local council and government laws that are working within the Resource management Act in the interest of reducing pollution of main rivers and waterways used by the public for recreation or for drinking water supply. The size of your dairy effluent pond will vary and is dependant on the amount of area feeding into it and your rainfall expectations. As a rule of thumb the surface area of a pond can vary from 3 – 4 sq/m per cow.  Longer narrower ponds can sometime be more cost effective by the nature of their liner design and simpler installation methods. Pond design differs and is dependant on the type or level of breakdown required.  A deeper pond will reduce oxygen content and mostly allow only bacteria that can survive in that environment.  A shallower pond with a larger surface area increases available oxygen levels and light to the base of the pond.  Either pond design can have contributing equipment assisting the natural breakdown and degradation process including mechanical stirrers or air pressure pipes that “bubble” the pond and add oxygen.  “Duraliner” pond lining membranes can be used across a wide range of industries and a re popular for effluent pond lining, clean water storage, industrial storage, firewater storage, etc.  Choosing the right Duraliner pond lining membrane becomes important in respect of compatibility with your needs and requirements.  If longevity and reliable performance is your priority then it is likely that an EPDM liner is you first choice.  If a maximum service life of only 15-20 years is required then alternatives materials can be used for the liner and these included welded polyethylene based liners, HDPE (High Density Polyethylene liners) PPL Polypropylene based liners.  PVC (Polyvinylchloride) liners are also used in some circumstances. Each liner material has their advantages – and each has their disadvantages!, the trick is to decide on your priorities firstly then match the liner to the application. In today’s world - due to the relatively high costs of construction of the pond or dam itself and all its associated inlet pipework and drainage , plus the cost of consents etc, - it is becoming popular to install the best possible quality Duraliner “ EPDM “  liner material.  This type of liner tends to offer the best service life and trouble free performance as it has superior elongation properties (can confirm to ground irregularities),  Impact resistance (can resist puncturing from sharp objects better) and Ultraviolet resistance (life when exposed to the sun) mechanical or “ break” strength is also superior with EPDM damliner membrane. Installation of the Duraliner EPDM product is often by the owner – however some liner membranes are more susceptible to damage during installation and specialist crews are required to position. The HDPE liners whilst lower cost are more expensive to install and may end up being similar in cost overall. All of these liners are typically black in colour – as the carbon black component is a very very stable and natural UV inhibitor.   A soft layer of geotextile is typically laid onto the soil prior to placing the liner in place. In most instances a soft geotextile is required to assist with puncture resilience and general longevity of the pond or damliner membrane. Main Benefits of the EPDM membrane Duraliner:  Excellent resistance to temperature, High elongation capabilty, Excellent UV resistance (more than 20 years), Resists cracking with age, Superior puncture resistance, Can be repaired with simple adhesive patches permanetly, EPDM Duraliner is inert and safe for fish ( U.S Water Research Center), Simple to install and requires only simple tools and machinery to handle. Contact Redpath for a free quote our standard sized liners 15m x 30m  on Free Ph 0508 733 728  or email to redpath@redpath.co.nz Our other products can be viewed on www.standoffshelters.co.nz  or www.redpath.co.nz