Temperatures are generally mild with average temperatures of 15.5C and 26.5C for June and January respectively. Rainfall is more pronounced during the summer/autumn months, with the least rainfall occurring in July, August and September. The average annual rainfall is 1110mm and 1270mm for Nowra and Milton respectively. Follow links for more detailed climate information about Nowra and Ulladulla or go to The Bureau of Meteorology.
The geology is dominated by Permian age sandstones and siltstones. Older Ordovician age slates and shales make up the basement in the Clyde Valley with volcanic intrusions evident in the north of the City and at Milton and Bawley Point. The area is predominantly hilly or mountainous country to the west with a narrow coastal strip to the east. Most of the soils of the area are moderately to strongly acid and due to the parent geology most are of poor nutrient status with low water holding capacity. The high nutrient status soils of volcanic origin (e.g. Milton Monzonite) or alluvial origin (e.g. Shoalhaven Floodplain) have generally been cleared and represent very good agricultural land. This past clearing of vegetation (much of it rainforest) has had significant impacts on regional wildlife.
Flora and Fauna
Today eucalypt forests and woodlands dominate the area with cleared land being prevalent in the alluvial valleys and in regions closer to the coast. Various specialised flora and fauna have developed in the rainforests, wetlands, coastal sand dunes and heath areas.
Crown Land, State Forest and National Park make up 64% of the Shoalhaven land area providing significant habitat for flora and fauna. Diverse coastline habitats represented by beaches, estuaries, wetlands and lakes along the coast are important for both the biodiversity values of the Shoalhaven and commercially for recreational and fishing opportunities.
The Shoalhaven region includes a number of sensitive natural assets. The Shoalhaven River and estuary system, Jervis Bay, Coomondary Swamp and Lake Wollumboola and a number of other coastal lakes and estuaries all represent sensitive natural environments. High population growth rates in the Shoalhaven places considerable pressure on these natural resources, highlighting the need for appropriate management and investment.