California Crop and Soil Evapotranspiration

The goal of this publication is to provide water users, consultants, water agency personnel, and others throughout California with information that will: (a) help individual water users with irrigation scheduling and system design and (b) help agricultural water agency personnel with water balances and future planning. The tables in this publication represent the consolidation of results from thousands of annual ET simulations that accounted for crop, rainfall (wet, dry, or “typical”), soil, and irrigation method in each of 13 major ETo zones in California. The annual simulations used daily water balances at the soil surface, crop canopy, and soil root zone. When using these tables, one must keep the following in mind: The tables account for soil evaporation 365 days out of the year. Many other published ET tables ignore ET that occurs when a crop is not present. The crop/soil ET values assume typical surface (furrow, border strip, and basin) irrigation management (except for grapes in Zones 3, 6, and 8, where drip irrigation is assumed). Procedures for adjusting the ET values for special conditions, various irrigation methods, etc. are explained in this publication and in the original ITRC Report 02-001 (found at www.itrc.org). The ET values are given for irrigation scheduling and system design purposes. For persons interested in computing water balances, the ET values must be de-rated because in most fields there are some bare spots and areas with decreased vigor – meaning that the field average ET is less than the crop/soil ET in areas of the field with healthy crops

California Energy Commission Agricultural Peak Load Reduction Program Case Study: Kaweah River Power Authority and Tulare ID

Tulare Irrigation District (TID) is located on the east side of the Central San Joaquin Valley just south of Visalia, CA. The district receives water from Lake Kaweah through Terminus Dam as well as from the Friant-Kern Canal. TID is the single largest partner in the Kaweah River Power Authority (KRPA), which operates Terminus Dam and regulates the discharge from Lake Kaweah

Irrigation District Observations on Large Diameter, Low Pressure Pipeline Materials

There are approximately 1,400 miles of low pressure non-reinforced cast-in-place ( monolithic or CIP ) concrete pipe in California irrigation districts. Cast-in-place pipe was irrigation districts’ material of choice for large diameter pipelines from 1930 to at least 1980. Many of these pipelines were installed in the early 1900’s. They are predominately found on the east side of the San Joaquin Valley, from Manteca in the north to Visalia in the south. Most of these pipes are deteriorating and will need to be replaced within the next 10-20 years. Irrigation districts have attempted to find new ways to repair these pipes. However, their uneven dimensions (they were often made with crude local installation equipment), high density of repairs (meaning that the pipe wall thicknesses and cross sections now vary), numerous connections, and non-linear placement have ruled out using available pipe liner technology. The cost to line these pipes is about the same as the cost to completely replace them. Due to the high replacement cost and need for repair, the last decade has seen a switch away from cast-in-place pipelines to pipelines of other materials. However, up until now there has been no general consensus as to the best replacement option. In November 2002, the California Polytechnic State University (Cal Poly) Irrigation Training and Research Center (ITRC) met at Madera ID with representatives from eight irrigation districts and one engineering firm to discuss reasons for switching types of pipes, and what alternative materials might be available

Where is all that Water Going?

Some have proposed to conserve 4-6 Million AF/yr in Agriculture with pragmatic, economical measures. All we need to do is find the inefficiencies. Then we\u27ll get rid of them

General Irrigation Consumer Bill of Rights

Cal Poly ITRC, together with various irrigation industry leaders and the Irrigation Dealers Association of California, plus with assistance from the California Energy Commission and Pacific Gas & Electric Co., developed the Irrigation Consumer Bill of Rights (ICBR) in 1994

Adjustable Magnetic Coupler

Efficiency in terms of power consumption is vital and continues to be increasingly important. The use of adjustable speed pumps can reduce energy consumption and improve controllability of pressure or flows. One such technology, the MagnaDrive coupler, has been developed for service in a variety of applications

Chemigation and Fertigation Basics for California

Chemigation is the application of any chemical through an irrigation system. Examples of chemicals include insecticides, fungicides, fertilizers, water amendments, soil amendments, and compounds used to reduce plugging of drip emitters. Proper chemigation reduces energy consumption (less fertilizer, chemicals, and tractor travel) and improves crop quality and yields. Fertigation accounts for the majority of chemigation. The sophistication of fertigation knowledge and practices is at about the same level as drip/microirrigation was in the mid-1970s. A lot of equipment and chemicals exist, and many farmers use fertigation, but only a relatively small percentage of those farmers are sophisticated users

Benchmarking Irrigation

A few performance indicators (e.g., “efficiency”) have been included in irrigation jargon for many decades. However, at the Rome meeting we will have a comprehensive discussion on irrigation benchmarking. It will be easy to fall into a discussion of definitions and specifics. Prior to that, it might be helpful to consider the following aspects that will help to set the stage for the details