She went up to her high school graduation 1998, the CJD Youth Village Christophorusschule Rostock.
It starts with the SC Empor Rostock 2000. Their routes are usually 5-25 km long, sometimes longer. In 2002 she became world champion in the Open Water World Championships in Sharm El -Sheikh over 10 km and also gained a bronze medal over 25 km. With the World Swimming Championships 2003 in Barcelona, she won the bronze medal over 5 km and 25 km of the silver medal. In 2004, she succeeded at the world championships in open water swimming in a Dubai double: she became world champion in the 10 and 25 km.
With the World Swimming Championships in 2005 they fought a thrilling race with the Dutch Edith van Dijk than 25 km. They came on a par to the finish. First Kamrau -core stone was proclaimed as a World Champion with a tenth of a second ahead. The jury decided a little later that van Dijk won with three tenths of a second. Kamrau remained the silver medal.
The world title she won the 25 km at the World Swimming Championships in 2007 in Melbourne. On 25 March 2007 she won confidently with 2:27 minutes ahead of the US-American Kalyn Keller and the Russian Xenia Popova. The race had been canceled the day before due to weather conditions at half the distance, at a time when Kamrau already clearly in the lead.
On November 26, 2005, she reached the 2nd place in the TV -total- high diving. On November 24 2007 she managed the same success again.
Britta Kamrau has a degree in law at the University of Rostock. On 27 June 2012 she was appointed as a judge in Mecklenburg-Vorpommern.