Headloss through filter pack Headloss through filter pack Sowega (Civil/Environmental) (OP) 6 Jun 13 16:02 Need help figuring headloss through a groundwater well filter pack. I'm thinking it would be something like headloss through a sand filter but I can't find a formula that quite fits. RE: Headloss through filter pack fattdad (Geotechnical) 11 Jun 13 09:06 I think there are tables/graphs in this publication. http://armypubs.army.mil/eng/DR_pubs/dr_a/pdf/tm5_... f-d ¡papá gordo ain’t no madre flaca! RE: Headloss through filter pack tkall (Civil/Environmental) 11 Jun 13 21:12 Sowega: Your question made me remember I had the same question several years ago. I had a bright engineer working with me and we decided to build a model of the filter pack/well in the office and measure the headloss as a function of pumping rate. It worked great and accurately predicted the response of the actual well in the field. RE: Headloss through filter pack dgillette (Geotechnical) 12 Jun 13 18:17 Just curious, tkall, how did the head loss through the filter compare with head loss through the well screen? What do you use for allowable velocity through the screen? I think somebody told me 0.2'/s for permanent wells, and 0.5'/s for temporary dewatering wells, but that was a few years ago. Thanks, DRG RE: Headloss through filter pack tkall (Civil/Environmental) 12 Jun 13 19:21 dgilette: It was a long time ago and I don't remember the details. We built an exact replica of the well on a barrel added a pump and measured the headloss. Pretty basic but instructive.