CITRUS CROP
CURRENT SITUATION
CORRECTION RE: TREATY "COMPLIANCE"
THE SIX TRIBUTARIES
FIELD HEARING
OTHER WATER NEWS

CITRUS CROP-

The season is finally about over-only a couple of packinghouses are still operating, but they will probably close in the next two weeks or so. The grapefruit crop estimate still shows a lot of fruit to be harvested over 15 percent of the total, but most of us believe the estimate is still too high.

We have shipped about 1.2 percent more fresh grapefruit this season-but eliminated only about 61 percent as much. That comparison shows how good fruit quality was this year; fresh utilization is about 68 percent this season, up from 58 percent last season.

CURRENT SITUATION-

Continued hot, dry and windy weather prevails, resulting in high evapotranspiration in groves. Irrigation is the major concern of growers and caretakers, but pest monitoring should not be overlooked.

The final major fruit drop period is over, so the 2002-03 crop is now on the trees. Navel oranges, of course, will undergo another couple of drops, including late summer fruit splitting. If current conditions prevail into July, the navel splitting problem could be more severe than normal.

At this point, grove practices are designed to keep the fruit free of pests, to size the fruit and to provide adequate growth for next season. The latter includes management/control of leaf problems such as greasy spot and various mite and insect pests. Naturally, soil moisture (from irrigation and rainfall) impacts all of the above, as pests and diseases need water, too-either directly or indirectly.

CORRECTION RE: TREATY "COMPLIANCE"-

In Vol. 16, No. 5 of the Valley Citrus Notes, May, 2002, I wrote an opinion piece entitled "Compliance". I subsequently learned of the specification of Minute Order 234, dated December 2, 1969, and signed within two weeks by officials of both Mexico and the United States. Minute Order 234 did not change my conclusion that Mexico is not in compliance, but it did invalidate the statement that any deficiency "be made up from the said tributaries" as indicated in Section II, Article 4 of the treaty.

Specifically, Minute Order 234, part 2, states "That in the event of a deficiency in a cycle of five consecutive years in the minimum amount of water allotted to the United State from the said tributaries, the deficiency shall be made up in the following five-year cycle, together with any quantity of water which is needed to avoid a deficiency in the aforesaid following cycle, by one or a combination of the following means:

a. With water of that portion of said tributary contributions to the Rio Grande allotted to the United States in excess of the minimum quantity guaranteed by the Water Treaty,
b. With water of that portion of the said tributary contributions to the Rio Grande allotted to Mexico, when Mexico gives advance notice to the United States and the United States is able to conserve such water; and
c. By transfer of Mexican waters in storage in the major international reservoirs, as determined by the Commission, provided that at the time of the transfer, United States storage capacity in available to conserve them."

In the simplest of terms, Minute Order 234 does not allow for back-to-back deficiency cycles; instead, it spells out that Mexico must make up the 1992-97 deficiency of 1,023,849 acre feet while also providing the 1,750,000 acre feet due in the current cycle. With only 105,187.08 acre feet credited to the current cycle as of April 20, 2002, there were only five months and 10 days left for Mexico to come up with 1,644,812.92 acre feet of water. Obviously, such volume of water is not forthcoming and Mexico will again claim "extraordinary" drought as the reason, despite all evidence to the contrary.

For those who see the 1944 Treaty as too old and outdated for modern times, there have been 307 minutes orders to date-which averages more than five minute orders per year-all signed by officials of both governments. Upon signing, a minute order becomes an official and integral part of the treaty. Many deal with boundary markers, but many more deal with water, particularly water of the Colorado River and water for Tijuana-so one wonders how folks in Sonora and Baja feel about the treaty, as this same treaty provides 1,500,000 acre feet annually as an absolute minimum to Mexico from the Colorado River. The United States has never failed to deliver that minimum in any year.

So, there was no "extraordinary" drought, no accident to the hydraulic system, only 430,000 of the promised 600,000 acre feet under Minute Order 307 and no plan by December 31, 2001, for future deliveries on the deficit. That does not meet any known definition for compliance.

THE SIX TRIBUTARIES-

The 1944 Water Treaty identifies the Rio Conchos, Rio San Diego, Rio San Rodrigo, Rio Escondido, Rio Salado and Arroyo Las Vacas as the six tributaries to the Rio Grande between Fort Quitman and the Gulf of Mexico, from which 350,000 acre feet must be provided to the United States annually, averaged in cycles of five years. A number of us recognize El Cuchillo and Marte Gomez reservoirs on the Rio San Juan, which currently have about 413,462 usable acre feet of water in storage. However, all waters of the Rio San Juan (and the Rio Alamo) are allotted to Mexico.

IBWC's website reports the storage in seven dams on the Rio Conchos, two on Rio San Diego, one on Rio San Rodrigo and one on Rio Salado. Presumably, there are no dams on Rio Escondido or Arroyo Las Vacas. The usable water in storage in all of the above 11 dams was assessed as 618,572 acre feet on May 29, 2002 (down 60,800 acre feet during May). With only 243,000 acre feet in Falcon/Amistad on May 23, clearly Mexico does not have sufficient water to avoid an even greater deficit in the current cycle.

Ignoring the Rio Conchos for the moment, where are the other named tributaries to the Rio Grande? Perhaps knowing a little about them would help us to understand just where rainfall is needed in order to furnish any water.

Arroyo Las Vacas heads in the mountains about 75 miles west southwest of Del Rio. It is entirely in Coahuila, entering the Rio Grande at Ciudad Acuna/Del Rio. There no are dams on it.

Rio San Diego heads about 20 miles closer to Del Rio than Arroyo Las Vacas and closely parallels it as it flows almost due east about 60 miles to enter the Rio Grande about 25 miles downstream from Cd. Acuna/Del Rio. Centenario has a capacity of about 21,100 acre feet; San Miguel has a capacity of about 15,400 acre feet. The current usable storage of the two dams combined is about 8,900 acre feet. Rio San Diego lies entirely in Coahuila.

Rio San Rodrigo heads in the next valley south of the Rio San Diego, running mostly easterly some 65 miles to enter the Rio Grande across from Quemado. It is entirely in Coahuila. La Fragua has storage capacity for about 36,500 acre feet, but contains no usable water at present.

Rio Escondido is another short tributary that lies entirely in Coahuila. Only about 65 miles long, it heads southwest of Piedras Negras, and flows northeast to enter the Rio Grande at Piedras Negras/Eagle Pass. There are no dams on Rio Escondido.

Rio Salado heads about 90-95 miles due south of Del Rio and flows parallel to the Rio Grande for some 70-75 miles to the confluence with Rio Sabinas some 35-40 miles southwest of Laredo. From there, Rio Salado flows another 45-50 miles into Falcon Reservoir southwest of Zapata. Rio Sabinas has several feeder tributaries that head further west and southwest of Del Rio than the first three tributaries above. Other tributaries head within 50-60 miles around Monclova, Coahuila, (about 125 miles west southwest of Laredo), and join together to flow into Rio Sabinas just before the latter crosses from Coahuila into Nuevo Leon. It is at that confluence on Rio Sabinas where Venustiano Carranza has a capacity of 1,122,833 acre feet, but contains only 60,800 at present. Still another tributary to Rio Salado heads to the west of Monclova, Coahuila and runs approximately 200 miles to join the Rio Salado just a few miles before the latter enters Falcon Reservoir.

Rio Alamo waters all belong to Mexico. It heads just north of Monterrey, Nuevo Leon, flowing north and then east to enter the Rio Grande at Cd. Aleman/Roma.

Rio San Juan waters all belong to Mexico. Its tributaries head around Monterrey, Nuevo Leon, flowing east and then north to enter the Rio Grande at Camargo/Rio Grande City. El Cuchillo has a capacity of 1,447,117 acre feet, with about 257,000 usable at present. Marte Gomez has a capacity of 905,563 acre feet, with about 156,467 usable at present. El Cuchillo is in Nuevo Leon, Marte Gomez is in Tamaulipas. In fact, Marte Gomez is within about 15 miles of Roma and Rio Grande City-and it declined about 94,000 acre feet during May.

And now, the Rio Conchos. Its 500 or so mile course to the Rio Grande is entirely within Chihuahua, beginning about 100 miles west of Chihuahua. It flows south, then east to Cd. Camargo, Chihuahua, then north past Delicias and Chihuahua to meet the Rio Grande at Ojinaga/Presidio. It is joined by numerous tributaries all along its route, though most come from the south and southeast of Chihuahua.

Seven impoundments (San Gabriel, La Boquilla, F.I. Madero, Pico de Aguila, Chihuahua, El Rejon and Luis L. Leon) have a combined capacity of 3,598,741 acre feet. Only about 608,002 acre feet existed as of May 1, 2002. The closest impoundment to the Rio Grande-Luis L. Leon, is about 75 crow-flight miles, but it has only about 29,185 acre feet of water. Approximately 75 percent of the current waters are in La Boquilla near Cd. Camargo. It's about 150 crow-flight miles from Ojinaga/Presido, probably 250 river miles away from the Rio Grande.

Given the geography of the area, there are actually two major watersheds sandwiched around the Chihuahuan Desert, which itself lies between the Sierra Madre Occidental to the south and west and the Sierra Madre Oriental to the east. The Rio Conchos watershed is basically the east side of the western Sierra Madres plus the Chihuahuan Desert.

The watershed for the other five named (and most of the unnamed) tributaries is roughly the east slope of the eastern Sierra Madres Oriental. That is more or less the area from the southern tip of the Big Bend south by southeast towards Saltillo and Monterrey, all of which is generally within about 120-140 miles of the Rio Grande. For the geographically challenged among us, Monterrey is not south of us. In fact, it is only a few minutes of latitude south of 26°N latitude, which runs through Brownsville. Ergo, Monterrey is nearly due west of Brownsville.

Given the current storage levels in the two watersheds, the Rio Conchos/ Chihuahua system needs more than 3,049,891 acre feet to fill up. The Coahuila watershed would need 1,145,570 acre feet to fill up. The Nuevo Leon system, which belongs entirely to Mexico, would need 1,935,159 acre feet to fill up. I include the Nuevo Leon system only because almost any storm that could put water into the Coahuila system would normally have to pass over the Nuevo Leon system.

Combined storage in Amistad and Falcon is over 4,715,900 acre feet below conservation level. Current combined US and Mexican water is 1,088,783 acre feet as of May 29.

FIELD HEARING-

At the field hearing of the Congressional Committee on Water and Power in Brownsville on May 3, a Mr. Durham provided testimony for the U.S. State Department. He testified that Minute Order 234 does require that Mexico repay the 1992-97 deficit in 1997-02 without running another deficit in 1997-02. He also testified that Mexico failed to comply with Minute order 307, by providing only about two-thirds of the 600,000 acre feet that was specified and by failing to develop by December 31, 2001, a plan for future deliveries of the deficits. Mr. Durham also testified that President Bush raised the issue with Presidente Fox as the first item on the agenda for their meeting in Monterrey.

Both Congressman Ortiz and Congressman Rodriguez asked Durham if the State Department is considering any penalties or sanctions should Mexico fail to deliver the deficit as called for in Minute Order 234. Durham responded that Mexico can't pay it, that State is pushing for some water now and is awaiting a response from Mexico. He was almost adamant, however, in refusing to discuss possible sanctions or penalties, insisting instead that State will wait until the end of September and assess the situation at that time. Given the speed at which State has acted on this matter for the last four years, one would not expect much any time soon.

OTHER WATER NEWS-

There have been a lot of reports, but little that you can hang your hat on. We are all waiting for Presidente Fox's promised repayment schedule that is due to be announced May 30. (Note: The announcement has now been delayed until next week!). The "Tractorcade" protest at the Pharr bridge came off without a hitch.

And the shutdowns have started, La Feria Irrigation District quit pumping on May 23, which is about five weeks earlier than it did in 1998. Other districts are soon to follow.

The "big" rains of two weekends ago were exciting at the time, but precious little in terms of quantity. From what I heard or saw, everybody got something, but not a whole lot anywhere. Most of the gullies, washes and arroyos I crossed between here and Laredo several days later were still flowing some water towards the river, so there should be a little additional 50-50 water at the end of this month's IBWC accounting cycle. And a series of storms blew through on May 29, bringing additional rainfall to Hidalgo, Cameron and Willacy Counties.

JULIAN W. SAULS, Ph.D.
Professor & Extension Horticulturist
2401 East Highway 83
Weslaco TX 78596