A mother and daughter died on board a boat in Windermere after inhaling high levels of carbon monoxide

An investigation into two motorboat deaths in Windermere in 2013 has found that a modified external exhaust system was to blame.

Carbon monoxide filled the cabin of the Bayliner 285 where mother and daughter, Kelly Webster and Lauren Thornton, were sleeping on 1 April after pipe work in the engine bay became detached; leaking toxic fumes into the boat.

Ms Webster’s partner, Matthew Eteson owned the vessel and had been onboard at the time but survived the incident.

A report by the Marine Investigation Branch has found that the external exhaust system fitted to a generator had been modified to incorporate a silencer by the boat’s owner, which detached, causing fumes from the generator to fill the engine bay and spread into the boat.


Mr Eteson, a plumber by trade, had reinstalled his generator for the new season on 31 March 2013 and added the silencer to the external exhaust system following comments from other lake users regarding the noise it produced.

Despite testing the modified system prior to installation, under load, it failed catastrophically, causing the generator to vent fumes into the boat.

An MAIB report said: “The materials and methods used to construct the external exhaust system were unsuitable and the testing of the generator without an electrical load was unrealistic and misleading.

“The external exhaust system fitted to the portable generator was not fit for purpose. It was not gas-tight and was likely to fail in a number of places because of the use of soft solder, unsuitable compression joints and because the system was unsupported.”

A carbon monoxide alarm had been fitted onboard the vessel but was seven years past its replacement date and had been disconnected from the power supply.

“The absence of at least one functioning alarm meant that a vital barrier to protect the boat’s occupants from the dangers of CO was not in place. Had a stand-alone alarm been fitted, it would have activated within three minutes of the hazardous concentration of carbon monoxide being detected,” the report added.

“DIY is very popular with recreational boaters, but there are numerous systems on board boats that, regardless of a boat owner’s engineering and mechanical skills, should only be installed, maintained or modified by a qualified marine engineer following manufacturers’ instructions.”

Mr Eteson was charge with manslaughter by gross negligence in June last year.