►Planning & Development ►Erosion and Sediment Control

Erosion and sediment control for building sites

For site disturbance less than 2500m²

The problem

Soil erosion on building sites can be a major source of sediment pollution in our waterways.

Truckloads of soil may wash from building sites if adequate controls are not in place resulting in:

• sediment of our river and like systems

• blocked stormwater pipes

• increased risk of flooding

• increased cost of maintenance

• loss of soil as a valuable landscaping resource

The solution

Erosion and sediment controls must be implemented on all residential building sites.

The following principles will assist you in providing effective erosion and sediment control measures on site.

Prepare an Erosion and Sediment Control Plan.

• assess your building site to determine any natural features or constraints

• construction should be planned to maximise undisturbed parts of the site and to retain as much vegetation as possible

• plan for deliveries, storage, waste and access to minimise site impacts

All development applications proposing site disturbance, excavation or filling must be accompanied by an erosion and sediment control plan except in the following circumstances:

• the construction of minor structures including carports, pergolas, verandas, garden sheds and the like

• dwelling additions and alterations which are deemed by council as not likely to cause erosion and sediment loss from the site.

The erosion and sediment control plan must show the location and type of all control measures proposed to be implemented on site, as well as any significant site features, for example dam or water course. A sample plan is attached for your information.

For single residential buildings, this plan may be a written statement where site disturbance is less than 2500m², provided that the statement must clearly detail the control measures to be implemented.

What to do

1. Retain vegetation

• fence or tape off those areas to remain undisturbed

• limit vehicle movements on site to avail compacting soils and destroying tree roots

• existing vegetation on the footpath areas is to be retained as this provides an effective sediment filter

2. Control site access

• limit access to one point only

• stabilise the access point by using gravel or crushed concrete with a minimum aggregate size of 50mm

• control vehicular access to ensure that soil is not tracked from the building site on to the roadway

• vehicles are to park on the stabilised access point or on the roadway - under no circumstances are vehicles permitted to park on the footpath area

3. Sediment control

• provide sediment fencing below all construction sites to slow and filter sediment laden runoff

• ensure all sediment fencing is installed correctly, in accordance with the manufacturer's recommendation

4. Stock pile topsoil

• retain stripped topsoil for reuse during landscaping and site rehabilitation

• protect stockpiles by erecting sediment fencing on the down slope side

• do not place stockpiles in drainage lines, depressions or around trees and shrubs

5. Washout areas

• do not wash-out barrows, paintbrushes, brick cutters and other tools in the street gutter

• provide a designated wash-out area which will detain and filter polluted water

6. Control stormwater

• where possible, use grassed or natural drainage channels to slow and filter runoff

• retard the rate of flow to non-erosive velocities using sediment fencing of straw bales across the line of flow

• connect downpipes to the stormwater system before placing roof materials

• backfill all trenches and compact to a level at least 75mm above the adjoining ground level

7. Maintain your site

• erosion and sediment controls must be maintained throughout the course of construction and until the building site has been rehabilitated and stabilised

• stabilised access points are to be replenished as necessary to maintain their effectiveness

• all control measures are to be inspected after each storm and cleaned if required

• accidental spills of soil or other materials onto the roadway or gutter must be removed prior to completion of the day's work - spills are to be removed by sweeping, shovelling or a means other than washing.

8. Site Rehabilitation

• reuse topsoil for landscaping and revegetation

• stabilise disturbed areas by turfing, mulching, seeding, paving or similar

• retain all excavated and filled areas

Benefits

Some of the benefits that can be realised through effective erosion and sediment control are:

	a better company image able to show environmental responsibility
	a more appealing site to potential purchasers
	reduced down time following wet weather
	fewer problems with both mud and dust
	reduced clean up costs
	a better relationship with council and less chance of incurring penalties
	reduced environmental degradation of our waterways
	fishery resources will be available in the future

Tips

	Establish erosion and sediment controls on the site before any earthworks commence
	inspect and maintain erosion and sediment controls throughout the project
	keep a site diary to record site conditions and actions taken to prevent environmental degradation
	minimise disturbances to existing vegetation on the site immediately construction has finished
	stop waste water from construction activities entering the stormwater system