The river's water quality is good, with most indexes showing that it is not far from being unpolluted enabling it to support populations of fish, while the lakes provide significant habitat for large numbers of birds.

The Poulter rises at a spring to the south west of Scarcliffe in Derbyshire, close to the 520-foot (160 m) contour, and skirts around the southern edge of the village, before flowing in a north-easterly direction towards Nether Langwith.

Owl Sick, a stream which rises at Owl Spring in Scarcliffe Park joins it near the village, and is joined by a stream which rises near Whaley Hall Farm, and flows in a south-easterly direction through Whaley and the Poulter Country Park.

The mill pond has become silted as a result of the poor condition of the dam and sluice, but could form a central part of a conservation area based on Apsley Grange, a large building on the opposite side of the road.

A lake called Cuckney Dam, covering 8.2 acres (3.3 ha),[5] provided the water to power its replacement, which ceased operation on 12 July 1844.

Flowing around the northern edge of Cuckney, the river reaches the site of a second corn mill which was situated to the east of the village.

In the 1760s, the duke employed the architect and civil engineer Robert Mylne to construct a three-arched bridge, which had to be both functional and beautiful.

[12] In the 1840s, the fifth duke, who built an underground ballroom and tunnels on the estate, employed the engineer William Tierney Clark to construct a suspension bridge.

The resident engineer for the project was Bland William Croker, who had assisted Clark with the construction of the Szechenyi suspension bridge in Budapest.

In 1695 10 acres (4.0 ha) of land were leased to John Wheeler of Worcester by the duke, on which he built the forge, a dam pool and floodgates.

Restoration of the historic structures was undertaken by the County Council in 2010/11, and interpretation boards have been erected to enable visitors to understand the process.

The Clumber estate was described in the 18th century as "A black heath full of rabbits, having a narrow river running through it, with a small boggy close or two.

[22] The bridge, which consists of three unequal arches with balustrading along the top, was designed by Stephen Wright, and is 230 feet (70 m) long.

[27] In spring 1845, 1846 and 1847, the duke drained the lake to make it wider and to improve the banks, which he felt looked "neither natural nor handsome" in places.

The house supply came from an artesian well, and was pumped to an underground reservoir, which held 60,000 imperial gallons (270 m3), from where it travelled 0.5 miles (0.80 km) by gravity.

The difference in levels of the two parts of the lake was sufficient to power a Gilbert Gilkes and Gordon turbine, which drove the pump.

The lowering of the water level during this work revealed the charred remains of the Lincoln, a one-third scale naval frigate which the Duke bought in 1871, and which was destroyed by fire in the 1940s.

The source of the Poulter is in a region where the underlying geology is an extensive water-bearing porous rock structure called the Magnesian Limestone aquifer.

Further to the east, the Magnesian Limestone is covered by a layer of porous rock called the Triassic Sherwood Sandstone aquifer, which is the major geological component of the area.

The Environment Agency use a six-stage rating scale, from 'A' to 'F', the General Quality Assessment, to classify rivers.

Figures for the final section before it joins the River Idle show that the levels of ammonia and dissolved oxygen are those which would be expected in a natural ecosystem.

There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish.

Like most rivers in the UK, the chemical status changed from good to fail in 2019, due to the presence of polybrominated diphenyl ethers (PBDE) and mercury compounds, neither of which had previously been included in the assessment.

The river above Welbeck Lake provides habitat for a significant population of wild brown trout.

Hobbys frequent the reed bed below Clumber Dam in August and September, where they hunt swallows and martins.

The upper lake is fringed by oak, yew, beech and Scots pine trees, and provides habitat for willow tits and woodpeckers, with blackcaps visiting in the summer.