It is understood that standing water in and around facilities can cause severe structural damage. Potential problems include cracked foundations due to static water pressure buildup on the wall, settling, degradation of adjoining building materials, and freeze–thaw issues. Similarly, ponding (i.e. water collection) and hydroplaning on roads, highways, and bridges are possible safety hazards that can be avoided.

Effectively handling and transporting away rainfall during and after storms is a prime component in facility and road construction planning.

Surface drainage can be accomplished using three different systems - in-line pits, open swales, or grated trench drains. Cost comparisons have shown modular trench drains to have lower total installed costs when labour, excavation, pipework, grading etc., are taken into account.

On average, pre-cast modular trench drains cost about 10 percent less to install and maintain than grated pits, and 20 percent less than cast-in-situ trench drain systems.

The design of V profiled drains is inspired by sewers with egg shaped profiles where liquid velocities need to be maximised during low flows.

During average rainfall, water levels in ACO’s channels will be higher (due to their V shape) and therefore will run cleaner as sediment tends to be washed downstream due to the resulting higher velocities. This means that the trench drain is clear and ready for the peak design storms.

The design of V profiled drains also yields a stronger wall profile

Trench drain systems employ a simple angled grade on both sides of a linear trench to move runoff into a point along the channel. Liquids are then discharged at the end of the drain into an underground pipe system or culvert. Trench drains need a shallower excavation than in-line pits with extensive underground piping.

Cast-in-situ systems are one type of trench drain design. This method uses extensive formwork and labour required for producing and installing the system. A form is built (usually wood) and concrete is poured around it and the form removed to leave a trench. Most cast-in-place systems are usually 300mm and 400mm in width, and possibly wider. These large widths require oversize grates, which drive up project cost dramatically

Modular trench drains are another way to produce a trench, Modular trench drain channels are typically factory manufactured and offered in metre or half-metre lengths to enable easy transport to the jobsite, on-site handling, and versatile configurations.

Modular channels usually start at 100mm wide. These narrower widths use smaller grates, significantly reducing overall project costs. Wider systems are available if required by hydraulics or application.

Channels are aligned onsite via male/female interconnecting ends to form a continuous sloped run. Systems offer up to 40 interconnecting sloped channel depths (sizes) to create continuously sloped trenches up to 40 metres long. Neutral channels with no slope that can be inserted along runs to extend length.

'POLYCRETE' is ACO's trademark for products made from polymer concrete produced in Australia. It encompasses ACO's extensive portfolio of polymer concrete pits, channels, ducts, lids, risers and containment sumps.

Polymer concrete is a durable material which is resistant to road salts and common chemicals. It is made from polyester resin reinforced with mineral aggregates and fillers.

Polymer concrete is a versatile, durable, composite material produced by mixing a variety of mineral fillers with a synthetic or natural resin binding agent. This advanced engineering material is used in many industries but is most common in the building and construction industries where its long life and material properties make it ideal for many products.

While polymer concrete provides effective durability in general applications where stormwater or dilute detergents are used, certain industrial applications require drainage of liquids that are corrosive, at extreme temperatures or both. Stainless steel is recommend for these applications.

Polymer concrete has a coefficient of expansion and contraction similar to portland cement, and so they will expand and contract at the same rate as the encasement, minimizing buckling or pulling away from the concrete surround. They have a low rate of water absorption and will not fail structurally during freeze-thaw cycles.

Except for the visible grate, most of the trench drain system is underground and virtually invisible. So the grate must work together with the channel to provide the right load classification performance (AS 3996) and visual qualities.

Grates come in a variety of different materials such as ductile iron, galvanised steel, stainless steel, non-ferrous metals and plastics.

Grates that comply with the requirements for pedestrian & cycle areas (AS 3996 & AS 4586) and  disability access are available (AS 1428.2).

AS 3996 
"This standard specifies requirements for access covers and grates for use in vehicular and pedestrian areas. It applies to access covers & grates having a clear opening of up to 1300mm...." Clause 1.1 Scope.

As part of ACO's continuous product development and commitment to quality, ACO has NATA certified testing equipment (Licence number 15193), operated by fully trained and certified technicians.

EN 1433 
The only standard written specifically for grated trench drains, and internationally recognised, is DIN 19580. EN 1433 is superseding DIN 19580. It accounts for different widths of grates, with different size test blocks for different size channels. EN 1433 tests products in exactly the same method as DIN 19580 with the same load categories, up to 900kN.

As with DIN 19580, EN 1433 offers test methods for both the grate and channel body. It accounts for both proof loading and catastrophic failure.

ACO in Australasia offers an extensive portfolio of stormwater, building drainage systems; electrical pit and ducting systems; access covers and other products for niche applications.