For many years access to this area has been restricted as it was set aside as a Water Board Catchment Area. NPA has maintained a long interest in the O’Hares Creek catchment. In 1985 Macarthur Branch completed a proposal for the area to be dedicated as a nature reserve.

In 1994 the State Government dedicated most of the catchment as a Crown reserve and allowed limited access to the area (bushwalking and cycling). The Crown Reserve was managed by a Trust comprising community members and representatives of a number of State agencies. The newly elected Labor Government dedicated most of the Crown Reserve area as a State recreation area under the control of the NPWS in 1996. An area of approximately 500 ha remained as Crown Reserve to allow for the construction of a rifle range.

Despite its classification as a Water Board catchment area, extractive industry was allowed on the edges of the catchment at several locations. The extractive resources have been found to be of little significance regionally and the State Government has recommended that extractive industries be phased out within the catchment. Today clay extraction for bricks and tiles occurs at one site along the Appin-Bulli Road.

In 1999 Noel Imports Australia submitted a development application to Wollondilly Shire Council for the resumption of clay extraction from a mining lease area that had not been worked since 1992. The proposal was to commence extraction from areas within the mining lease that had not previously been mined. These unmined areas include sections of the upland swamps that form the upper reaches of Stokes Creek, a tributary of O’Hares Creek.

NPA Macarthur Branch was one of several groups and individuals to object to the proposal, and made a detailed submission outlining concerns about the impact of the proposed development on the environment. These include the likely impact on water quality of O’Hares Creek, the destruction of a significant area of upland swamp, the loss of threatened species including Pultanea aristata (a threatened plant) and the loss of scenic amenity values. The Healthy Rivers Commission also raised serious concerns about the sustainability of extractive industries in its draft report into the Georges River-Botany Bay system.