Here are four irrigation discussion groups you may want to consider subscribing to. I have been a member of Irr-L for years and have found it invaluable. The information below came from the following website: http://www.trickle-l.com/new/onthenet/
There are four distinct irrigation discussion groups: Irrigation-L, Trickle-L, Salinity-L and SoWaCS.
The purpose of Irrigation-L is to cover technical aspects of irrigation like design, hydraulics, and system layouts. It is also open for topics like irrigation management, socio-cultural, political and economic questions relevant to irrigation.
Trickle-L focuses on all aspects of drip irrigation technology that is sometimes referred to as Microirrigation.
Salinity-L discusses the management practices of saline soils along with more detailed discussions of salt movement in the soil and crop salt tolerance.
SoWaCS or Soil Water Content Sensors is a discussion list which obviously focuses on methods and techniques used to measure soil water content and soil water potential.
All of the above discussion groups are operated by a listserver. A listserver automatically distributes an e-mail message from one member of the list to all other members on the list. When you subscribe to a list, your name and e-mail address is automatically added to it. To subscribe to any of the four lists above, send in the E-mail message (without the quotes), “subscribe (name of list) your name to the following addresses:
For IRRIGATION-L: LISTSERV@listserv.gmd.de (or if this doesn’t work use LISTSERV@listserv.dfn.de)
TRICKLE-L : http://list.vi-dev.com/listinfo/trickle-l
For Salinity-L: LISTSERV@crcvms.unl.edu
For SoWaCs: Majordomo@aqua.ccwr.ac.za
When you subscribe using one of the above email addresses, put SUSCRIBE ###-L (where ### is IRRIGATION or TRICKLE or Salininty or SoWaCs) and YOUR NAME in the subject line, with of course YOUR NAME being your own name.