SARA is the designated rescue service for the Rivers Severn, Wye and Usk*. The SARA lifeboats, based at Beachley and Sharpness are tasked by HM Coastguard, largely in response to 999 calls.
The River Severn below Gloucester is used for around 350 commercial ship transits per year and the lower Wye around 150. The Severn also has over 500 registered leisure craft transits between Gloucester and Sharpness alone each year, and many more that are not counted. The tidal range on the Severn at Beachley, and on the Wye at Chepstow, is 15 metres (the second highest in the World!), which means that the river changes within a few hours from a wide expanse of deep water, to narrow shallow channels weaving through extensive sandbanks.
In addition the tidal current on the Severn reaches 12 knots; this can lead to very turbulent river conditions in even a moderate wind. Most of the way to Gloucester the riverbed is very broad, with a narrow and winding navigable channel, marked with numerous buoys, beacons and transits. The margins of all the tidal rivers have wide and thick mudbanks below the high-tide levels, and in places the exposed mud leads out to rocky islands at low tide.
Typical incidents for SARA include vessels grounding, or losing power hence requiring urgent assistance to avoid grounding. People have been rescued from islands or ledges where they were being cut off by the tide, or actually plucked from the mud. On other occasions boats, and other floating hardware, are broken loose by the water and drift with the fast currents, and have to be recovered. On average lifeboats are launched operationally around once a week (50-60 launches per year).
*SARA’s declared area of lifeboat operations, for which it is tasked by HM Coatsguard, is the Severn, north from a line between Newport and Clevedon to Maisemore Weir near Gloucester, and the tributary rivers Wye (to Bigsweir Bridge), Usk (to the M4 Bridge) and the Avon (to Bristol Docks). If required in exceptional circumstances, SARA Lifeboats 1 and 20 can extend beyond this area, using a re-fuelling stop at Newport, to operate north of a line from Barry to Weston Super Mare.