The group profit for the six months until 30 September 2014 is £108.3 million, down from £344.8 million in the same period the previous year.
Severn Trent also stated it will let go about one in ten of its employees over the next six months to meet its efficiency savings targets as part of its plans for the next AMP cycle.
The dramatic fall in profits was due to an “exceptional credit” rebate the company received last year, of £153.6 million, whereas this year it paid £29.9 million in tax.
The Severn Trent Group also posted a loss of £24.2 million via its use of financial instruments in the 2014 H1 results, which compares to a £61.1 million gain in the 2013 H1 results.
The results also state that the interim dividend will increase by 5.6 per cent, from 32.16 pence per share (p/s) by H1 2013 to 33.96p/s this year.
However, the group turnover increased to £947.6 million for H1 2014, up 2.7 per cent on the previous year.
Underlying group profit before interest and tax (PBIT) also increased, from £141.3 million to £155.8 million (10.3 per cent).
For the regulated part of the business, Severn Trent Water, the underlying PBIT increased by 2.1 per cent to £275.1 million.
The results state that the group is trading in line with its financial expectations for the six months until 30 September 2014.
Severn Trent chief executive Liv Garfield said: “Looking forward to AMP6, we are progressing with the organisational changes required to deliver our plan and we will bring forward additional capital investment to ensure we are in the best place possible to start the new regulatory period.
“The enthusiasm and passion I am witnessing in our people gives me every confidence that we will hit the ground running on 1 April next year.”
The results also stated that Severn Trent Water will introduce a new social tariff which will give discounts of up to 90 per cent on the average bill for qualifying customers. And that the scheme will be administered by the Citizens Advice Bureau from April 2015.
The water company will also extend the “no risk” period for customers switching to a meter to 24 months from 12 months at the same time.