Background

Situated in the Chihuahuan Desert at the base of the Franklin mountains, El Paso has an arid, warm climate. Although the average annual rainfall is only about 8 inches, the city is subject to torrential rains during the summer monsoon season between July and September.

In the summer of 2006, El Paso experienced a series of torrential rains that produced severe flooding in many areas of the city. More than 15 inches of rain—nearly twice the annual average—fell in less than two weeks. The flooding caused serious infrastructure damage to roadways, the sewer system and the storm drainage system itself, as well as to businesses and private property.

El Paso has an extensive storm drainage system that includes 38 dams, 270 retention ponds and more than 500 miles of storm drain conduits and open canals. However, the system has not been well maintained and in many areas is undersized. Until 2008, storm water management was shared by various departments within the city and county, and there was no dedicated funding, which had left flood control projects to compete with other priorities.

In response to this situation, the City established a separate utility—the Municipal Drainage Utility System (MDUS)—to operate and maintain the storm water system, commissioned a study to assess the existing system and developed a master plan for its improvement. The master plan identifies and recommends more than 100 major storm drainage improvements costing approximately US$650 million. MDUS is proposing to implement the first phase of this comprehensive capital investment program over a period of three years.

Description

The proposed project consists of the following works in the Central, East, Mission Valley, Northeast, and Northwest watersheds of El Paso:

• Expansion of street inlets and reservoirs;
• Enlargement and construction of culverts;
• Increasing the capacity of channels;
• Clearance and relocation of existing utilities;
• Construction of storm drains, ponds, pump stations, force mains and sediment basins;
• Improvement of dams;
• Replacement of undersized crossings;
• Re-grading of interceptors; and
• Lining of channels.

Benefits

The project will help prevent potential flooding and related mud slides, thus protecting human life, property and the environment. Improved flood control will in turn reduce the risks associated with the transmission of waterborne diseases and human contact with stagnant and/or contaminated water. It will also reduce erosion and sedimentation from storm runoff, as well as the amount of silt washed into the Rio Grande. System improvements will also help recharge the Hueco Bolson aquifer, one of the main sources of drinking water for the El Paso-Ciudad Juarez region, which has been rapidly depleted in recent years.