Internal flooding incidents - The number of internal sewage flooding incidents per 10,000 properties that are caused by events other than insufficient capacity of our sewerage network (We capture issues around insufficient capacity of our system in the next performance commitment). This measure includes flooding incidents caused by blockages and asset failures.
This was one of the measures for which Ofwat set an industry wide target representing current upper quartile performance. As we were already an upper quartile performer our target was set tighter than this level at 1.66 incidents per 10,000 properties in 2019-20; equates to c205 incidents.
As a high customer priority this measure has the potential for both customer refunds and incentive payments. To account for the impact of weather on this measure we have a deadband around the target. This means that we will refund customers if we miss the target by over 0.2 (c25 incidents), and we can claim incentive payments if we beat the target by more than 0.13 (c16 incidents). We will refund £315k for each 0.01 we are over the deadband and we can claim an incentive payment of £204k for each 0.01 we are below the deadband.
In 2018-19 our performance was 1.43 sewer flooding incidents (c179 incidents) per 10,000 properties which is a significant improvement and this results in an incentive payment of £2.4m. Whilst this is an out-performance of our target, it is not in line with what we forecast I 2017-18. This is a result of an unusually large increase in incidents in November 2018, from a variety of different causes such as blockages (e.g. from rags, fat and tree roots) and damage to pipework. On review of our performance, our forecast for 2019-20 is an average of our performance from 2015-2019.