focus on natural waterway assets that provide a stormwater conveyance service, such as urban creeks and streams.
What are "Natural Waterway Assets"?
Natural creeks, wetlands, lagoons and coastal lakes provide a range of values to urban neighbourhoods. In recognition of these values, some local councils are seeking to better integrate their management of natural waterway assets on council land into corporate asset management and planning activities.
What do we mean by "Natural Waterway Assets"?
It’s not easy to arrive at a universally accepted definition of "natural waterway asset" however this is not a barrier to establishing 'natural waterways' as an asset class. Asset Management is grounded in systems thinking - where a particular asset's classification is derived from its relationship with other assets.
This is not inconsistent with the NSW Local Government Act, which does precisely define what a "natural area" is, but sets "natural area" as one option when Councils are requried to classify Community Land (Division 2, s36). The Act also requires that “Natural Areas” are further classified as either bushland, wetland, escarpment, watercourse or foreshore. Whilst no definitions are provided, the Act sets out core management objectives for each type of land (S36E).
There may be more pressing questions to resolve when getting started with taking an asset management approach to natural waterways.
Is it on land that is under Council's care and control?
The reasons why a council might resolve to formally 'register' natural assets on council land are explored
here. Once this decision is made, asset managers and planners have some pragmatic information needs. They will want to know:
What assets do we have on our land and where are they? (a mapping question).
How does a particular asset relate to other asset types? (a classification question).
What attributes are best used to describe it? (an asset registration question).
Most NSW councils - particularly those in urban settings - manage a continuum of waterway types - from natural creeks with intact riparian vegetation and no history of 'capital works; to constructed earthen drainage channels to concrete stormwater drains.
These resources offer examples of basic ‘classification frameworks’ for urban waterways that may work for your council:
Gold Coast City Council’s classification system for drainage channels.
Australian Runoff Quality, Engineers Australia, Chapter 16.
Stream classification is common to the disciplines of freshwater ecology and stream hydrology, which offer sophisticated frameworks to consider the complex ecological, geomorphological and biophysical processes at play within natural systems. Such expertise offers vital information about catchments as well as stream condition, hydraulic performance and reach recovery potential - giving practical insights into realistic "management" interventions for natural waterway assets.3
More about getting started on natural waterway asset management
REFERENCES:
1. CRC for Freshwater Ecology and CRC for Catchment Hydrology 2004
2. Breen, P. and Lawrence, I. in Engineers Australia, 2006
3. Anderson, J, Centre for Coastal Management Southern Cross University, LWRRDC Occasional Paper 8/99
Basic Decision Support System for Management of Urban Streams, from Report No. 1. Development of the Classification System for Urban Streams.