From LimeSurvey Manual
There are multiple ways to delete your survey. The most common one is from the survey list. For more details, click on the following link.
A "delete survey" button can also be found under the Tools menu:
A message will be displayed asking you to confirm once more if you really wish to delete the survey and its corresponding groups, questions, subquestions, answers, responses, and conditions:
- We highly recommend our users to export the survey and its corresponding responses table before deleting it.
- The responses table is getting archived and it can still be recovered for a limited period of time. However, for the sake of simplicity and to avoid further import-related complications, we recommend our users to also backup the responses table.