Release notes v16.1.5
The following updates have been implemented from the recently published publication P110 (Swedish Water, 2016):
1. Guidelines for selecting the climate factor in the box Design flow. The scroll list is deleted to simplify the use.
Default is still the factor of 1.0, which means that no climate factor is used which relates to cases before exploitation.
This is the default for the user to make a choice. The factor of 1.25 is normally used for dimensioning of sewers, ditches and gutters. The factor 1.20 is normally used when designing for flow detention.
2. Default recurrence time is changed from 10 to 5 years incl. instructions for the areas and cases in which other return periods are recommended.
3. Modified design runoff coefficient of residential areas. Default design runoff coefficient is used for the design of transport systems and flow detention has been increased for the land use residential aeas, with different coefficients for different sized plots. The corresponding volume runoff coefficient for the calculation of the annual flow and annual pollution loads have not been changed.
4. Incorporation of a safety factor in accordance with P110 Part II for the dimensioning of sewers and ditches, with automatic warning symbol when respectively calculated safety factor is too small and the next higher dimension is recommended.
5. The guide Design flow is updated with instructions from P110.
6. The list of recommended Manning´s numbers for the design of ditches and gutters have been updated with values from P110.
Soon the remaining updates within the frame of P110 will be performed, which specifically consist of a) a complementary method for the calculation of natural land drainage; b) a complementary calculation of runoff coefficients with respect to that coefficients increase with increased rain intensities.