La Limpia and Getting the Ditches Ready

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(The following is an excerpt from
The Mayordomía Handbook and Field Guide, developed by the NMAA to help serve as a practical guide for a new mayordomo or mayordoma in training.)
The first water and the spring are periods of most importance for acequias. It is recommended that for the first water, a crew follow the water as it flows through the acequia in its entirety. Debris and loose dirt from the limpia are removed during this exercise. As we all know, the springtime is the period when high winds, rain, etc., can occur without warning. Tumbleweeds can quickly plug a culvert or headgate and water backup can occur with the accompanying release of water outside the banks of the acequia. Water can damage buildings, walls, septic tanks and several other structures. So, early in the irrigation season is when danger from storms is the greatest.
A mayordomo’s daily routine during the middle of the irrigation season has to include giving the rounds. What this means is visiting trouble areas (culverts, low slope areas, diversions, and headgates) on a regular basis, daily if possible. You will, with experience, be able to identify all the trouble areas on your acequia.
After a short period of time, a mayordomo gets to know the landscape of his/her acequia. By studying the speed of the water flowing at various sections of the acequia during normal periods, a mayordomo can tell when the flow of water is just not right. Usually this indicates a blockage (slow moving flow) or breakage (fast moving flow) somewhere in the vicinity. Sooner, rather than later, a mayordomo will be able to count the number of trouble spots on his/her acequia. Usually a weak slope in the acequia, an improperly sized culvert or headgate, are likely trouble areas. Needless to say, troubleshooting known trouble spots becomes second nature to the mayordomo who knows his/her acequia like the palm of his/her hand. Troubleshooting is important throughout the irrigation season.  
When the flow of water is just not right, one of several scenarios can be taking place. Depending on your diversion structure, you may need to adjust the flow very frequently or flush out sand and silt. During normal conditions, a diversion structure diverts a fairly constant amount of water. A blockage can change the amount of diverted water quickly as can a storm event. A mayordomo must be a weatherman whether he/she likes it or not. Familiarize yourself with your watershed and then you will be able to predict the amount of water arriving at your diversion structure. Get to know when the dark clouds above your watershed are threatening, and then you can quickly get to your diversion structure and adjust things accordingly. When you are away make sure you leave someone in charge to include monitoring the local weather.
Daily maintenance activities must include the flushing of the acequia at various points along it and checking of debris screens and culverts. Most acequias have sand traps that need periodic flushing so that the acequia does not fill up with sand and silt. The turbidity (cloudiness) of the water will dictate how often the acequia sand traps need to be flushed. Usually, once a day is required during the early run off period or during a rain storm. Culverts and headgates tend to be troublesome in that debris (weeds, branches, etc.) tends to get hung up on them. Some culverts and headgates have trash screens and these need cleaning periodically throughout the day especially during the windy season. The spillage of water over the banks of the acequia is usually caused by a backup at a culvert. Depending on the amount of water flowing out of the acequia, varying amounts of damage to property can take place.