Two natural assets that are under stress and need concerted attention if they are to measure up to Canberra’s iconic status are Lake Burley Griffin and its principal source of water, the Molonglo River, and the region’s lowland woodlands and grasslands.

Lake Burley Griffin and its principal source of water, the Molonglo River, are in poor ecological health 2. Both have high sediment and nutrient levels transported from land higher in the catchment that has been modified for farming, grazing, mining and forestry. High sediment and nutrient levels have encouraged and favoured alien fish species such as carp in the lake and algal blooms are common in the warmer months.

Although the Australian Government makes significant investments in the buildings and grounds of the parliamentary triangle, this is not matched by similar expenditure on the Mnatural assets at its centre (e.g. Lake Burley Griffin).

The lowland open woodlands and grasslands of the ACT favoured for agriculture in the 19th century and more recently for urban development are now seriously depleted. They continue to be depleted as the city expands to meet demand for housing.

Figure 2. Land use in the ACT.

Converting woodlands and grasslands into social and economic assets (new suburbs, larger houses, more amenities) has been generally considered a necessary tradeoff against their loss. However, these natural assets are a limited, non-renewable resource – few are increasing; most are diminishing, in poor health or disappearing. It is time to set limits, particularly where feasible alternatives still exist. For example, the density of Canberra’s population within existing boundaries can be increased – European cities have an urban population density double that of Australian cities and are still attractive places to live and visit.