Infiltration Trench using BRE DIGEST 365 method

Thanks a lot and Really appreciated

That is a great idea and I agree with you that it will benefit users who are doing some prelim calcs from the outset. I will start the consultation process with a wider array of stakeholders to gauge their interest and gather additional perspectives on the proposed feature.

Should we observe a substantial level of enthusiasm and demand from our customers, we will be inclined to advance the status of this suggestion to "Under Consideration."

This stage will involve a more detailed analysis, including a feasibility study, resource allocation assessment, and preliminary planning to understand how this feature could be seamlessly integrated into InfoDrainage.

Hi Sam,

Appreciated & Thanks for your response,

if it is the case, could we add BRE 365 method in Preliminary sizing check rather on the simulation check. At least this will give us how the software works on this compare to BRE 365 method. Looking forward your support.

Hi Sam,

Thanks for the response. I am sure that you are right in terms of calculation the software is using and its accuracy (and ultimately true to life representation), however in UK Lead Local Flood Authorities do require BRE365 method even if it is more conservative and so it would be useful if we could use software to do this rather than hand calculations. Sorry for any troubles...

Thank you for the further clarifications and comments, we will review the equations provided with the development team but from a quick glance, my first guess is that the differences between the manual calcs and the software calcs is the fact that the software is calculating the infiltration in every timestep dynamically using the inflow and the outflow at 0.1 second timestep, then it rationalises the results to provide them at 1min output intervals. Using hand calcs, you're only looking at a lumped inflow and lumped outflow. But at the end of the day, the software is doing the same concept to maintain the mass balance and to ensure that Inflow - outflow - storage = 0 which is checked at every timestep. My guess is that hand calcs would be more conservative and software calcs would be more realistic if we're comparing like for like scenario.

Hi Sam,

I do not think the guys are missing the infiltration rate calculator as such. Source Control (not sure about Infodrainage though) was trying to replicate BRE365 but it would appear that the actual equations used are different and so the results of source control and hand calculations were different. BRE365 uses specific few equations that are not complicated and I think these equations are not at the moment used by the software hence the discrepancies between software and hand calculations (even for the exact same rainfall data).

Thanks for the prompt response

BRE Digest 365 is provides infiltration test method as well as calculating required length of infiltration trench by Inflow, Outflow and storage volume formula. please refer the attached details. Since we are using infodrainage software for all drainage system analysis we need this BRE digest 365 calculation procedure to be supported in software.

Thank you for the suggestion and thanks to those who voted.

I would like to highlight that the BRE DIGEST 365 method is a best practice method to establish the infiltration rate on-site by digging a hole and filling it with water three times and monitoring the time that it takes the water to go down from 75% to 25%. InfoDrainage as a drainage design and analysis software does not use BRE DIGEST 365 in the analysis - no software does. This can be a simple calculator added next to the infiltration rate field but normally the supplier who tests the infiltration on your behalf can provide you the infiltration rate and InfoDrainage would use the rate in the analysis.

If the calculator is what you're suggesting, then I agree with you, it would be nice to have it in the software but again, it will only calculate the infiltration rate once you do the site experiment three times and record the longest time out of the three experiments. BRE DIGEST 365 is not an analysis method so won't be something to include in InfoDrainage.

If I have misinterpreted your suggestion, please let me know.