The last progress report noted that Scottish Water was delivering the 2010-15 investment programme as directed by Ministers. Following the conclusion of this period, assessments were made by the Output Monitoring Group  and Scottish Water's economic regulator, the Water Industry Commission for Scotland  on Scottish Water's achievements. Both reports concluded that Scottish Water hade made significant improvements to services during the period. Furthermore, the Water Industry Commission for Scotland concluded that Scottish Water had outperformed the regulatory settlement by delivering levels of customer service that were beyond those demanded and for £122 million less than allowed.
On the 1 April 2015, Scottish Water began to deliver the investment requirements for the 2015-21 period as directed by Minister on the 1 October 2014.  The Outputs Monitoring Group is carefully monitoring the delivery of the improvements in line with Scottish Water's delivery plan  and quarterly reports are published on the Scottish Government's website.
Scottish Water reported for the financial year 2014-15, that it had invested £470 million and in doing so had made a further contribution towards a number of the Government's key strategic objectives. This investment enabled it to: deliver better services to customers; improve drinking water quality; provide additional capacity to meet the demands of new housing; reduce leakage; and protect Scotland's environment. Examples of improvements are:
- leakage has been reduced by a further 20 million litres a day. Overall leakage is half what it was in 2006;
- levels of customer service is now amongst the best in the UK; in 2009-10, Scottish Water ranked amongst the worst;
- environmental compliance has improved significantly over the last five years with significant reductions in numbers of pollution incidents and failing wastewater treatment works. In 2014-15, there were 5 failing Wastewater Treatment Works compared to a target of 18 and 249 pollution incidents compared to a target of 548. This compares to 39 and over 939 respectively in 2009-10; and
- drinking water quality has improved steadily. In 2014, 99.90% of the 318,000 samples taken met strict quality standards.
In the current regulatory period 2015-21, Scottish Water will invest £3.6 billion in Scotland's water and wastewater services.
Scottish Water's investment programme is defined and funded for the period 2015-21. The investment programme is set out in the form of Ministerial Directions and a supporting Technical Expression in the form of a list of outputs. Scottish Water's Delivery Plan sets out how Scottish Water intends to deliver the investment over the five year period. The current period ends on 31 March 2021.
The Strategic Review of Charges undertaken by the Water Industry Commission for Scotland was completed on 20 November 2014 when it published its Final Determination of Charges  .
This determined the amount that customers need to pay in order deliver the necessary improvements to services. It confirmed the agreement that the Customer Forum  had negotiated with Scottish Water on behalf of customers on prices and levels of service represents the lowest overall reasonable cost for customers. The agreement concluded that household charges should not rise by more than the Consumer Prices Index less 1.8% over the six-year period.
The 2015-21 investment plan contains many thousands of projects. Key projects to be delivered in the 2015-21 include:
- major upgrades to Glasgow's sewerage networks and Wastewater Treatment Works at Daldowie and Dalmarnock Wastewater Treatment Works; and
- improvements to drinking water quality in Ayrshire including the construction of a new 30 mile long water main.