The DESC contains a database of soil types and 30 years of daily rainfall records for many sites throughout New Zealand. Use it in conjunction with details and measurements from your farm including farm management and milking practices.
New online DESC version
There is now an online version of the Dairy Effluent Storage Calculator (DESC). The upgrade was made as the software the old version was based on was outdated. With the update and moving online there has been the opportunity to add additional functionality into the DESC.
The calculation is not exact – some parts of the original calculator were written with the coding and functionality available, some things like calculating the 90th percentile used different calculations as there were no standard functions to calculate this available – now a simple, standard function is in use, and the end result approximately the same, but not exact.
The soil risk framework was also developed after the calculator had been developed, and the inclusion of a limit on drainage above an agreed 10mm for low risk soils has been included to align this with the FDE code of practice.
We recommend that final calculations are done by Dairy Effluent WOF assessors, Accredited Effluent System Designers or other suitably experienced individual. There are a number of critical data that should be checked to ensure the calculation is valid, also there are scenarios that can be run that if implemented could reduce storage requirements, and enough knowledge is needed to do these appropriately.
DESC calculator website Download calculator (Massey version)
Using the Dairy Effluent Storage Calculator
Before using the calculator it's important that you first read How to use the Dairy Effluent Storage Calculator as it is easy to misuse. We recommend that you always get a professional who has done the Massey FDE course, the Dairy Effluent WOF course, or similar and has experience to check your storage volume calculations as getting this wrong can be costly.
How-to videos
The short videos below explain all of the input and output tabs and how to correctly enter farm information into the calculator.