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Repository for information learned about Irrigation Channels aspect of project.

Questions to ask NGO's, Professors, PE's, etc.

Propose two questions that would be best answered by someone with experience...most immediately these questions are for the FLUNCH with professor Porporato, but they may also be asked of EIA, TERRA, or other Duke professors. Try to get these questions posted by Monday, February 1st.

Q1. Are there any good software programs that will incorporate survey and elevation data in order to produce a suggested layout for irrigation channels?

Q2. Would simple sluice/check gate mechanism like the one shown on p4&5 of the attached document be sufficiently for our flow control needs? or is a more incremental float control capacity needed to maintain a steady, efficient and manageable supply of water in out channels?

Q3. What are the optimal locations for any check valves or variable flow control valves in the channel system? will we need checks only along the branches from the main trunk? will we need periodic control points even just along the main transfer lines? where are there potential trouble spots in general, regarding maintaining predictable flow and avoiding turbulence and overflow.
Q4. ...
Q5. ...
Q6. ...

Fundamentals Concepts for Irrigation Channel Components

Structural Design of Channels (Philip Danser)

  • Triangular channels used for small rates of discharge, and trapezoidal cross sections for large flows; nearly vertical channel sides may be used in rocks and stiff clays, whereas side slopes of 1vertical to 3horizontal may be needed in sandy soils. (source: Chapter 9, Open Channel Flow by M. Hanif Chaudhry; 2008)
  • For erodible channels, channel size is selected such that the mean flow velocity for the design discharge is less than the permissible flow velocity (Vp). Above Vp, channel bottom and sides are eroded.
    • Vp is primarily a dependent on the type of soil and the size of particles, and moderately upon flow depth and curvature of channel path. Typically ranges from 0.6m/s for fine sand; 1.8m/s for clay.
  •  Trapezoidal cross sections typically used for erodible channels

Terrain Considerations and its Effect on the Routing of Channels & Look into Various Softwares (Judy Jow)

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Connection of Channels to Retention Pond & Fields (Mike Fausone)

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Potential Resources

Great Starting Point / Overview For All Teams:

FAO Irrigation Water Management: Introduction to Irrigation
http://www.fao.org/docrep/R4082E/R4082E00.htm

Field Techniques

FAO WATER HARVESTING
take a look at pan evaporation method, possible for site assessment?
http://www.fao.org/docrep/u3160e/u3160e04.htm#TopOfPage

Surveying Techniques
http://www.fao.org/docrep/u3160e/u3160e0a.htm#TopOfPage)

FAO Guidelines for designing and evaluating surface irrigation systems
Section 3. Field Measurements
http://www.fao.org/docrep/T0231E/t0231e05.htm#3.%20field%20measurements

Channels

Terra - Resource Development International
An NGO that has been conducting groundwater research near Oruro. They have been working with researchers from Stanford University and the Technical University of Oruro. As we begin to discuss sustainability issues, such as the effect of a borehole on the region's groundwater table, we will plan to contact them for advice. The article mentions issues that we have talked about before... such as how melting glaciers threaten the altiplano's water supply will eventually force people away from agriculture & their homes and into the cities. Terra also has technical experience with boreholes and irrigation channels.
http://www.environment.arizona.edu/news/terra
http://www.terradevelopment.org/projects/current_projects/capiri/capiri.html

FAO How design, management and policy affect the performance of irrigation
specifically look at section entitled 'Specific Design Issues'
http://www.fao.org/docrep/004/ac799e/ac799e03.htm#bm3.6.5

FAO The Irrigation Challenge
http://www.fao.org/DOCREP/006/Y4854E/Y4854E00.HTM

FAO Guidelines for designing and evaluating surface irrigation systems
see 2.4 'Surface Irrigation Structures'
http://www.fao.org/docrep/T0231E/t0231e04.htm#2.1%20introduction%20to%20surface%20irrigation
see 3. Field measurements
http://www.fao.org/docrep/T0231E/t0231e05.htm#3.%20field%20measurements

Water Supply

FAO Irrigation Water Management: Scheme irrigation water needs and supply
Section 2. Water Sources and Water Availability
http://www.fao.org/docrep/U5835E/u5835e03.htm#2.%20water%20sources%20and%20water%20availability

Resources To Bring To Bolivia

SOIL SURVEY STANDARD TEST METHOD
Methodology for determining soil types.

Soil samples generally cannot be brought back to the Unites States from a foreign country. It is possible with a permit, but samples must be shipped via a bonded carrier. More details at: http://www.aphis.usda.gov/plant_health/permits/organism/soil/soil_under3pounds.shtml

As far as I could tell, there are no restrictions on importing water.