Laserfiche WebLink
<br />The Problem and Approach <br /> <br />The City of Tijuana is facing an increasing population in need of a larger supply of <br />potable water as well as more space for parks and open areas. With more people, more <br />industry, and more urbanization in the region, increasing amounts of contaminants are <br />deposited in Tijuana's urban rivers and aquifers. In the Alamar River Corridor, water <br />pollution continues to affect groundwater quality, thus reducing supplies of potable <br />water. In addition, the existing land use activities in the river floodplain, such as the <br />irregular settlements and sand mining, are damaging the riparian habitat. <br /> <br />Riparian vegetation provides numerous benefits to Tijuana's residents. During rainfall <br />and flood events, riparian vegetation slows and dissipates storm water flows (Dallman <br />and Piechota 2000). This slowing of water first prevents erosion and sedimentation <br />downstream. Second, it allows for the floodwater to percolate into the soil and eventually <br />into the aquifer beneath the riverbed, providing an important source of potable water for <br />urban residents (Campo EPA 1994). In addition, riparian vegetation in the Alamar River <br />Corridor helps improve the water quality in streams, aquifers, and the coastal waters <br />downstream (Husted 1997). The destruction of riparian vegetation results in the <br />termination of the aforementioned benefits. Protecting and restoring the Alamar River <br />will help address all the specific problems discussed below including water siIpply, water <br />quality, biodiversity, and erosion problems. <br /> <br />The authors of this report advocate the use of a watershed approach for the protection <br />and restoration of the Alamar River. The watershed approach incorporates strategies for <br />not only the Alamar River region, but also upstream and downstream areas. By applying <br />the watershed approach, the city's water resources requirements can be augmented by <br />first capturing more water on site. Capturing water on site will increase groundwater <br />recharge and, thus, enhance the city's drinking water supply (Dallman and Piechota <br />2000). Second, preserving and restoring wetlands and riparian habitat will reduce <br />contaminants in the river and groundwater (Husted 1997). Third, the watershed approach, <br />as opposed to conventional engineering methods of river concrete channelization, <br />advocates the use of the riverbed and floodplain for green spaces and recreational areas <br />for Tijuana's residents. Instead of channelization, restoring the Alamar River will <br />improve property values near the river region, improve the quality of life for residents, <br />and improve the image of the city. <br /> <br />6 <br />