The stream courses down through the two valleys and along Hinksey Stream have running water throughout the year and contain interesting plant environments which include the Chilswell Valley and Harcourt Wood reedbeds which although small in area are a scarce resource in Oxfordshire. Other waterside plants in Chilswell Valley comprise golden saxifrage and the aromatic liverwort conocephalum conuium . In Harcourt Wood areas of swamp found in the valley have been formed by clay soils impeding the drainage (CRC, 1995). The common reed phragmites australis with the occasional reed sweet grass glyceria maxima and herbs such as meadow sweet filipendula ulmaria and greater willowherb epilobium hirsutum also occur.

There are two relatively new ponds located east of Harcourt Wood one near the nature trail and the other alongside fairway three of the golf course. A third pond is located to the west end of the woodland and this supports a marginal flora of common reed phragmites australis, reed sweet grass glyceria maxima, meadow sweet filipendula ulmaria, greater willow herb epilobium hirsutum and water mint mentha acquatica

Two shallow ponds located close to the entrance of the golf course from the ring roads have also been created in the last five years and are developing with similar marginal water plants to the above. The lower of these ponds dries out during the summer. A further shallow pond area, which is periodically dry, is located near the junction of the southwest parish boundary with Chilswell Valley.