Soon after flowing under Mitton Bridge, the River Ribble grows considerably where it is joined by the Rivers Hodder and Calder. The ‘Big Ribble’ continues through fertile pastoral land with a large amount of dairy farming and becomes tidal in Preston, Lancashire’s administrative centre. The Ribble Estuary flows past the fertile Fylde plain on its way to the Irish Sea, where the coastline becomes increasingly urbanised from Lytham St. Annes northwards towards the popular holiday destination of Blackpool.
The Upper Ribble catchment includes the source of the River Ribble at the confluence of Gayle Beck and Cam Beck near the famous viaduct at Ribblehead, in the shadow of the Yorkshire Dales three peaks in the National Park area above Horton-in-Ribblesdale. This area is lightly populated and the main use of land is for the rearing of sheep. As the Ribble flows through Ribblesdale and on towards Lancashire the land becomes more fertile allowing dairy farming on the pastureland. The principal towns include Settle in North Yorkshire, Barnoldswick and Clitheroe in Lancashire.
The Hodder catchment includes some of the most attractive landscapes within the Ribble catchment. The whole area is within the designated Forest of Bowland Area of Outstanding Natural Beauty and the uplands are in the Bowland Fells SSSI. The catchment has a highly valued fishery and is popular with anglers. Stocks Reservoir and other upland river intakes, provide a vital part of the North West’s public water supply. The Hodder valley is mostly agriculture with small rural villages including Dunsop Bridge and Slaidburn.
The Calder catchment includes the main River Calder which originates from the moorlands surrounding Nelson, Burnley, Colne and Accrington, before joining the Ribble below Whalley. All the tributaries that flow into the River Calder such as Pendle Water, Colne Water and Hyndburn Brook are also in this area. Historically this area was heavily industrialised (mill workings, paper production and so on) and much of the Calder and its tributaries were altered and impacted by industrial and urban development. The catchment is predominantly urban.