FAQs
Below you will find the most frequently asked questions about the registration process, the conduction of WFD studies and the WFD portal.
Questions about the Registration Process
The steps for a successful registration are different. It depends on whether your organization is already registered in the portal. You can find information on all registration options in this Tutorial.
Only registered users have access to further information about case studies, such as field reports and images.
Questions about the Conduction of WFD Studies
The tool requires exact values. If the values were entered with decimal places, make sure that the total including the decimal places is 100%. Another option would be to enter rounded values.
As indicted in the WFD user manual,
“ The data requirements of the “Scenario data entry” sheet differ compared to those of the “Baseline data entry” sheet in that they follow a simpler linear approach (waste generation > collection > treatment > disposal). This is due to the scenarios not necessarily having to be based of ground-based measurements and therefore they don’t have the same restrictions that were applied to the baseline data for quality control. For example, in the baseline method, the collection coverage and uncollected waste is calculated by comparing measurements of what is treated and disposed compared to that generated at source. The “Baseline data entry” sheet uses measured weights in tonnes as inputs. In contrast, the “Scenario data entry” does not require these measured data points as it assesses possible hypothetical scenarios. Instead, the “Scenario data entry” sheet largely uses percentages to split the initial waste generation across each stage of the solid waste management system. This approach has both advantages and challenges. By allowing percentage-based data inputs for each stage of the waste management system, interventions can be targeted at aspects that would not be feasible using the baseline approach. For instance, collection coverage (%) can be specified as an input and therefore analysed as an intervention. However, challenges with this scenario method involve how the user is able to adequately select percentages for these inputs if these cannot be directly measured”.
This is due to the fact that the total amount of waste generated is less than the total amount of waste collected and disposed of. Therefore, the division value will be >1, which brings it above 100%.
The error #N/A means “no value available”. This error can occur if some of the data entries in the “Value” columns are not complete or if the data has been entered in the wrong format. For example, if numerical values have been entered as text.
Otherwise, the error may occur when Excel converts the numbers to regional settings. The numbers must have decimal points as dots (.) and not as commas (,).
Please change this under >File>>Settings>>Advanced to decimal points.
Further information can also be found at https://docs.microsoft.com/en-us/office/troubleshoot/excel/formula-errors.
Baseline follows the linear data approach and therefore takes the data from the same column. In the “Scenario” column, on the other hand, we can define a condition based on the data entered for different scenarios.
This could be due to longer labels. Increase the chart width. This can be done in the Size & Margin section on the Sankey Matic website in the Excel tool when creating or editing the chart.
This error could be due to the fact that the amount of waste collected was calculated to be less than the amount of waste sorted and/or recycled and/or disposed of. Bring the % value for the total waste collected to >100.
The errors are due to an unbalanced mass or values divided by 0. Please check the values of the different subsections in section 5 of the baseline. If all values in even one of the subsections are set to zero, this tells the program that the divisor value is 0, which leads to errors.
This is due to the fact that the total amount of waste generated is less than the total amount of waste collected and disposed of. Therefore, the division value will be >1, which brings it above 100%.#DIV0 is the error value that is displayed when attempting to divide by zero. This error can occur if some of the data entries in the “Value” columns are not complete or if a zero value was mistakenly inserted into a cell.
The error checkboxes in the flow diagram and in the calculation sheet display a red cross if there is an error in the calculations. This is usually due to errors in the mass balance or due to flows that are calculated as negative.
This error can occur if the data input values are incorrect or if the assumptions and approximations used in the data input are not sufficient to balance the mass of the system. It is recommended that all data inputs and analyses performed are carefully checked, including those of the SDG11.6.1 method. The calculation sheet shows a detailed breakdown of where the errors occur in the mass balance of the system to help with troubleshooting.
What we need is the composition of total municipal solid waste generation, which measures the composition of household waste and disposed waste. When using the SDG 11.6.1 method, an additional step is required to calculate the composition of total waste generation. This method does not measure the composition of non-household municipal waste. Municipal waste includes household, commercial and institutional waste.
Clicking the Scenarios link opens up a page allowing scenarios to be created and modified.
This page also allows scenario results to be viewed and compared to baseline in tabular form as “Results” and “Unmanaged”.
The functionality is also provided to view the Waste Flow diagrams and Sankey diagrams for scenarios and baseline. In the case of baselines, the diagrams are watermarked “UNVALIDATED” if they have not yet been validated, so that readers know that they have not yet been validated when they are used in reports or presented to stakeholders.
Questions about the WFD Portal
Clicking on the “Publish” button will cause your study to be reviewed by the data curation team. After a successful review, the study will be released.
You can delete your case studies by clicking on the trash can icon below the case study in the user dashboard. You must be logged in to see the user dashboard.
As long as you do not click on the “Publish” button, only people from your organization will be able to see your case studies.
For guidance on using the WFD portal, please refer to the WFD Data Portal User Guide, which can be downloaded here.
