- Author: Ben Faber
Groundwater pumping may significantly affect growers' energy costs. As part of a California Energy Commission-funded research project, Lawrence Berkeley National Laboratory wants to hear directly from growers—via a short survey—about their experiences with the energy needed to pump groundwater. To learn more about the larger project, click here.
Your participation in this survey is greatly appreciated. We hope to understand more about the conditions you face on the ground so we can accurately convey your experiences with pumping groundwater to policymakers. We will be asking you some questions about your reliance on groundwater, past and planned well operation practices, and barriers to lowering the energy needed to pump groundwater. Results from this survey may inform future efforts to reduce energy use and costs for growers.
Your participation in this survey is completely anonymous. The survey software will not capture any personally identifiable information, including IP address. Individual anonymous responses will be stored in a secure location accessed only by a few authorized LBNL researchers, and will not be made public in any form. In publicly available reports, results will only be presented in aggregated form.
This survey should take around 20 minutes to complete. To preview the survey before taking it, a PDF version can be viewed here. If you are at least 18 years of age, own or operate a farm or ranch in California, and rely at least to some extent on groundwater for your farm or ranch operations, please click the link below to complete the questionnaire.
If you have questions about this survey or the larger project, or would prefer to respond to this survey over the phone, please contact us at email@example.com, (510) 486-6839 [Heidi Fuchs, Survey Lead], or (510) 495-2865 [Helcio Blum, Project Lead]. For issues related to your rights as a research participant in this study (LBNL HSC 382H001-31AU19), please contact LBNL's Human Subjects Committee at (510) 486-5399.
Learn more and take the survey at
Questions? Contact us at firstname.lastname@example.org or (510) 486-6839
Thank you very much for your time and participation!
- Author: Ben Faber
Sand media filters are commonly used in agricultural microirrigation systems. They have the advantages of simplicity and large capacities and are favored by many farmers and designers over other filtration hardware when there is a lot of organic matter in the water. The Irrigation Training and Research Center (ITRC) at Cal Poly San Luis looked at sand filters to see if it were possible to use lower-than-accepted backflush pressure and thereby reduce the total pressure required for irrigation systems. By lowering backflush pressure it would be possible to design a system that could run at an overall lower pressure and hence cost. The various components of microirrigation systems run at lower pressures than the backflush pressures recommended for most sand media filters.
The conclusions are:
There are substantial pressure differences amongst different models and designs during backflush and filtration
The main pressure loss is at the backflush valves
If designed right large backflush flow rates can be accomplished at low backflush pressures (this is critical for proper detritus removal).
There are substantial differences among underdrains of various models which affects pressure requirements
No large intimal high pressure was necessary to break up the media bed, a common practice.
Different underdrain designs create different patterns of cleaning the media.
There were substantial differences among models in the amount of sand discharged from the system at backflow rate of 190 GPM. Sand discharge should actually be avoided since it's an indication of preferential flow and poor cleaning.
These are some new ideas, and even though they are meant to reduce pressure and energy use, they are also good management suggestions.
If this strikes your fancy, read more at http://www.itrc.org/reports/mediafilters.htm