Landscape drainage

Summary
Quick reference guide for key criteria
Sub-surface drainage, subsoil drain, field inlet

Overarching requirements
Embellishments should be designed/selected and installed as follows:
- Fit for purpose, appropriately positioned and accessible.
- Durable, robust and safe (suitable for corrosive environments).
- Vandal resistant with parts that are easily replaceable.
- Easy to maintain (with appropriate warranty and workmanship).
- Comply with relevant standards, legislation, corporate documents and approvals
Planning, design and positioning
- Preserve existing overland flow paths
- Site overland flow paths within road reserve, parks or other council controlled land
- Indicate subsurface drainage, outlets and cleanouts on site drawings
- Design in accordance with IPWEA (Institute of Public Work Engineering Australia) standard drawings and QUDM (Queensland Urban Drainage Manual)
General requirements
- Site specific design by a drainage engineer
- Design to provide safe, water free surfaces for park activities
- Avoid designing drainage systems which require safety fencing (where possible)
(A) Sub-surface (or sub-soil) drainage system requirements
- A practice used to prevent water logging of soil
- IPWEA standard drawing RS-140 Subsoil Drains Details and Locations and RS-142 Subsoil Drains Access Points
- Materials – heavy duty PVC solid or PE corrugated slotted pipe suitable for buried applications
(B) Subsoil drain (perforated pipe) requirements
- Designed to remove excess water from the surrounding soil profile
- Materials – polyethylene corrugated slotted pipe
- Geofabric may be used to line trenches
(C) Field inlet and overflow gully requirements
- Field inlet and overflow gully must discharge to a soakage trench or a piped drain, appropriate for the site
- Grated cover – grate size and design by qualified engineer
- Materials – in-situ or pre-cast concrete pit covered with a galvanised steel lid, 316 stainless steel or aluminium grate. Where the use of metallic lids is required, lids are to be coated in a heat resistant, pedestrian grade anti-slip coating
- Drainage grates and covers – must be slip resistant
- Grates and pit lids – consider that metal grates and pit lids may retain surface heat
Note: Further guidance and clarification of the content on this page, can be found in the relevant sections of this information sheet.
Trench drain, swales, box and pipe culvet

Overarching requirements
Embellishments should be designed/selected and installed as follows:
- Fit for purpose, appropriately positioned and accessible.
- Durable, robust and safe (suitable for corrosive environments).
- Vandal resistant with parts that are easily replaceable.
- Easy to maintain (with appropriate warranty and workmanship).
- Comply with relevant standards, legislation, corporate documents and approvals
Planning, design and positioning
- Design in accordance with IPWEA (Institute of Public Work Engineering Australia) standard drawings and QUDM (Queensland Urban Drainage Manual)
- Indicate subsurface drainage, outlets and cleanouts on site drawings
- Site specific design by a drainage engineer
- Design to ensure water free surfaces (in average weather conditions), to prevent water logged areas and to handle peak loads
(A) Grated trench drain requirements
- Materials – hot dipped galvanised steel or 316 stainless steel with box drain grate, size determined by drainage engineer. Grates must be vehicle rated where traffic may pass over. Consider that metal grates may retain surface heat, where the use of metallic lids is required, lids are to be coated in a heat resistant, pedestrian grade anti-slip coating
- Trench drain – isolation joint and smooth transition required between adjacent finished surface materials
- Heel guard grate required, flush with adjacent finished surfaces
(B) Open flow channel (swales) requirements
- Vegetated swales – include turf (preferred), sedges and tufted grasses
- Keep velocities low within swales to avoid scouring
- Rock lined swales (not preferred) must be approved by asset custodian. Within 50 m of a playground, or where vandalism may be a problem rocks must be embedded in concrete or fixed with adhesive
- For mowing safety plant a low buffer both sides of a rock swale
- Provide maintenance vehicle access across or around a swale drain
- Sub surface materials must be suitable for buried applications
(C) Box and pipe culvert with overpass requirements
- Minimum recommended size 300 mm
- Most effective in natural drains.
- Select culverts for vehicle crossover, pedestrian bridge, fauna/fish/stock passage
- Materials – reinforced concrete, hot dipped galvanised steel, aluminium or high density polyethylene. Sub surface materials must be suitable for buried applications
- Culvert floor must be at the same level as natural drainage
- Avoid designing drainage systems which require safety fencing
Stormwater quality management considerations
- Infrastructure designed to improve or protect downstream systems from pollutants (not illustrated). Refer to LIM Water sensitive urban design (WSUD)
Note: Further guidance and clarification of the content on this page, can be found in the relevant sections of this information sheet.
Water management for paths/trails – waterbars, table drain, cross over, french drain

Overarching requirements
Embellishments should be designed/selected and installed as follows:
- Fit for purpose, appropriately positioned and accessible.
- Durable, robust and safe (suitable for corrosive environments).
- Vandal resistant with parts that are easily replaceable.
- Easy to maintain (with appropriate warranty and workmanship).
- Comply with relevant standards, legislation, corporate documents and approvals
Planning, design and positioning
- Surface/subsurface drainage, outlets and clean outs should be indicated on site drawings
- Design by a suitably qualified professional
- Designed to create water free surfaces and to prevent water logged areas
(A) Waterbar requirements
- Materials – natural finish stabilised soil, timber, stone, compacted road base
- Deflectors across a path/trail to divert surface water.
- Waterbars comprise a drain, a mound or a barrier full width across a path
- May be difficult for people with limited mobility
(B) Table drain (side drain) requirements
- Materials – natural finish lined with rock, free draining granular material/corrugated, perforated PVC pipe
- Path surface should be crowned or provide sufficient cross fall to direct water towards side drains
(C) Drain with pedestrian cross over
- Materials – hardwood timber crosses over a stone lined drain
- Timber must be arrissed prior to installation
(D) French drain requirements
- Materials – natural surface finish. Rock lined buried trench covered with gravel or rock, may be lined with geofabric suitable for steep slopes.
- Suitable for low flows only
Note: Further guidance and clarification of the content on this page, can be found in the relevant sections of this information sheet.
This component is currently in development