About the Tecate River Sub basin

The Tecate River Sub basin situated within the Tijuana River Watershed is a binational sub-basin straddling the U.S.-Mexican border. It encompasses 620 square kilometers and is characterized by steep hilly terrain, a Mediterranean climate, and is dominated by chaparral and coastal sage scrub, wetlands (vernal pools, and riparian zones) and conifers in the mountains . The sub-basin is predominantly rural and in 1998 was 88% non-developed. The major land use categories are agricultural (6.5%) and dispersed residential (3.1%) .Tecate River drains an area of approximately 39,660 hectares (Comer, 2001).

Water demand in the basin

As a result of population growth, the demand for potable water has increased steadily. With an average rainfall of only 10 inches annually, evaporation is greater than precipitation, causing substantial losses of water in the Morena and Barret dams in the U.S., and the Carrizo dam in Tecate. Eighty to ninety percent of the area is served by imported water from the Colorado, however flow has increasingly become inconsistent due to the construction of dams and growing diversions upstream.

One of the highest growth rates within the basin has occurred Tecate, the largest municipality within the basin, which has a current population of 67 000, and is expected to reach between 130,000 inhabitants by the year 2020 (Cruz Pineiro, 2002). This means that within 20 years it will be necessary to double the current infrastructure for not only water supply, but electricity, sewer lines and housing as well (Castro Ruiz 2002). This expected accelerated development has caused concern for the local government in Tecate, particularly in terms of water availability. In response, the government has called upon the private sector and relevant government departments to identify options that will secure future resources.

Two major options include the development of network maintenance and rehabilitation of infrastructure to adequately monitor use and reduce losses from leakages, and secondly, a quota increase from the Colorado River through modifications and expansions of   its current services.

The aim of the first option is to increase water use efficiency by reclaiming physical losses of water, which are currently estimated to be 24% of supply (Castro Ruiz 2002).  This is an expensive, but ultimately necessary solution that can be realized via:

· streamlining management function

· metering all service connections

· replacement of deteriorating infrastructure

· specific training of personnel with specified infrastructure facilities

· regular water audits

The cost of employing these actions may need to be met by a significant increase in water rates, which, can only realistically be implemented over the long-term.

The second solution is also a feasible option, however it may only be of benefit in the short term as there is a limit to how much extra water will be available from the Colorado River. Water allocations are likely to become more competitive and restrictive between Tecate and other upstream and downstream users, particularly in drought years. 

The solution to securing water resources for the future ultimately lies in the employment of conservation techniques  by all water users today, including  industry, agriculture and domestic sectors, and gaining a better understanding of the biological and physical processes involved in water movement. To discover ways in which you can help conserve water, follow  this link.  To find out how environmental modeling can help us understand the biological and physical processes involved in water movement, follow this link.

References:

Castro Ruiz, J. (2002). Tecate's Water Supply. In P. Ganster, F.C. Velazquez, J.L. Castro Ruiz, J & A. Villegas (Eds.), Tecate, Baja California: Realities and Challenges in a Mexican Border Community (pp. 177-185). San Diego, California: San Diego State University Press, Institute for Regional Studies of the Californias.

Comer, K. 2001.  Proposal for a Watershed Analysis in the Tecate-Campo Sub-basin. San Diego State University, San Diego CA (Unpublished).

Cruz Pineiro, Rodolfo; Ybanez Zepeda, Elmyra (2002). Demographic Dynamics of Tecate. In P. Ganster, F.C. Velazquez, J.L. Castro Ruiz, J & A. Villegas (Eds.), Tecate, Baja California: Realities and Challenges in a Mexican Border Community (pp. 17-34). San Diego, California: San Diego State University Press, Institute for Regional Studies of the Californias.