Excellent

Structure and function of habitats considered in natural or unimpacted condition. Waters are likely to be very nutrient poor. Adequate light for a maximum photic zone.

Very Good

Habitat structure considered natural, but some detectable changes compared to Excellent state. Habitat changes are unlikely to be leading to changes in ecosystem function. Any detrimental effects are limited to small pockets and likely to be reversible

Good

Habitat structure slightly impaired with initial symptoms of nutrient enrichment or suspended sediment.  May be some initial changes to ecosystem function. Detrimental effects limited to site level changes where recovery is possible

Fair

Habitat structure has been impaired with impacts from nutrient enrichment or suspended sediment.  These habitat changes are likely to be changing ecosystem function including resilience, biodiversity, productivity and sediment stability. Detrimental effects may extend to numerous sites or small areas where longer term recovery is required

Poor

Habitat structure has been severely impaired leading to significant changes to ecosystem function including resilience, biodiversity, productivity and sediment stability. Significant impacts from nutrient enrichment or suspended sediment. Detrimental effects may extend to numerous sites and long term recovery is required.

Very Poor

Ecosystem function and structure totally lost.  Waters are likely to be eutrophic and suffering significant impacts from excess nutrients. Detrimental effects at a regional scale and recovery may not be possible in generations.