View
2
Download
0
Category
Preview:
Citation preview
Agricultural DrainageAgricultural DrainageJ. Phillip King, P.E.,J. Phillip King, P.E., PhPh.D..D.
Associate Professor/Associate Dept. HeadAssociate Professor/Associate Dept. HeadDepartment of Civil, Agricultural, & Geological EngineeringDepartment of Civil, Agricultural, & Geological Engineering
New Mexico State UniversityNew Mexico State University
Drained ConditionUndrained Condition
Classes of Subsurface Drainage Classes of Subsurface Drainage DesignsDesigns
• Steady-state– Humid regions– Control steady water table
• Non-steady state– Arid, Irrigated– Drop water table after
irrigation/rainfall
• Interceptor– Protect cropland from
source of high groundwater
Primary Functions of Agricultural Primary Functions of Agricultural DrainsDrains
• Control of water table – root zone aeration– EBID– Drainage density of 20 f/acre
• Removal of salt from root zone– HCCRD– Drainage density of 22 f/acre plus field
systems
Yield effects of SalinityYield effects of Salinity
Drain Installation Drain Installation –– Then & NowThen & Now
Ca. 1900 Ca. 2000
The local drainage systemsThe local drainage systems
• Open ditch• Installed in 1920s-
1930s• Functions:
– Water table control– Salt removal– Storm water
conveyance– Operational spill return
Seasonal and LongSeasonal and Long--Term Drain Term Drain Hydrology Hydrology –– West DrainWest Drain
0
500
1000
1500
2000
2500
3000
3500
4000
4500
01/80 07/80 12/80 06/81 12/81 06/82 12/82 06/83 12/83 06/84 12/84
Mon
thly
Flo
w, A
F
0
10,000
20,000
30,000
40,000
50,000
60,000
1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985
Ann
ual F
low
, AF
Drain Water Quality Drain Water Quality –– West DrainWest Drain
0
200
400
600
800
1000
1200
1400
1600
1800
2000
05/79 12/79 06/80 01/81 08/81 02/82 09/82 03/83 10/83 04/84 11/84 06/85
TDS,
mg/
L
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Q, A
F/M
onth
TDS, mg/LQ, AF
Drain flows between the statesDrain flows between the states
LongLong--Term Salt BalanceTerm Salt Balance
• Mass Balance: QinTDSin - QoutTDSout• Elephant Butte to El Paso (Courchesne
Bridge)– 90,640 acres of EBID + 10,000 acres of
EPCWID• Courchesne Bridge to Fort Quitman
– 59,000 acres of EPCWID + 18,000 acres of HCCRD
– Mexico (???)
Salt Balance, Elephant Butte to Salt Balance, Elephant Butte to El PasoEl Paso
Salt Balance, El Paso to Salt Balance, El Paso to Fort QuitmanFort Quitman
The FutureThe Future
Legal Considerations– Possible changes in water quality regulations– Urbanization and municipal use of Project
Water– Changes in Project operation
• Environmental Considerations– Drains as habitat– Restoration efforts on drains– Illegal dumping in drains
Picacho Drain Bosque ParkPicacho Drain Bosque Park
• City of Las Cruces, EBID, and Southwest Environment Center
• NM Fish and Game land• Picacho Drain right-of-way• No increased depletion due to habitat
restoration– Offset open water evaporation with removal of
large, dense canopy salt cedar• Drain function is paramount
Picacho DrainPicacho Drain
Recommended