First series Ordnance Survey map covering the east of Birmingham. Red underlining shows all water mills

The map above indicates that there was a water mill for every five square miles, or thereabouts, in the area covering the centre of Birmingham and a considerable distance to the east. Not only were the mills few and far between, they were not very powerful. A typical example is Sarehole Mill. This was used for a variety of purposes from the usual corn milling and button polishing to making edge tools and rolling metal strip. The mill wheel is breast shot. This is a configuration that is used to maximise the force that is generated from a low water flow but the higher force is a trade-off with work rate, which is inevitably rather low. Matthew Boulton's father was a tenant of Sarehole Mill and Matthew took over the tenancy sometime around 1760. It was undoubtedly his awareness of the limitations of water power in the Birmingham area that led him to seek out James Watt and create the powerhouses of the Industrial Revolution.
Although Birmingham's water mills were poor things they have had a lasting impact on the face of the city. If the mid-nineteenth century distribution of mills shown above is compared with a modern A-Z of Birmingham it will often be found that there is a corresponding Mill Street. Even more significant is the effect on the shape of the city, which continues to this day. Many of the industrial concentrations which shape the urban area were obviously nucleated by the existence of a water mill. This is illustrated by the following table