Calexico New River Committee

Solution

Efforts to address the problem of New River pollution have been underway for decades, but have been frustrated by a number of factors:

• Mexico has instituted some improvements to its sewage collection and wastewater treatment systems, but its success has been limited by a lack of funding, the need to address higher priorities, and by explosive population and industrial growth within Mexicali.
• Mexico has been protective of its sovereignty, and at times has turned down offers of United States backed grants of low interest loans to build expanded sewage collection and wastewater treatment facilities within Mexico.
• The State of California legislature has refused funding for the New River projects within the United States, stating that it is an international problem, and, therefore, negotiating a solution is the responsibility of the United States federal government.

Proposed Improvements

Specific Improvements that will be part to the Project will include:

• The installation of an automatic bar screen (trash collector) right at the border.
• An enclosed canal (“box culvert”) to contain the rerouted New River where it flows through the developed area of Calexico, including overflow provisions. Other features will include a trash rack and increased security near the point where the Calexico New River enters the United States.
• Create an open space for recreational facilities such as walking/running trails and a soccer/baseball field in the area along the existing river channel.
• The cleaning of the River bottom and of the contaminated soil.
• Improve New River habitat efforts, such as native vegetation and restored or artificial wetlands, developed in cooperation with fish and wildlife agencies, to mitigate adverse impacts of constructing the improvements.
• Construct, North of Highway 98, primary treatment and wetlands for additional treatment.

The following proposed improvements will transform the Calexico New River and the encompassing Imperial County from it’s current condition, to an attractive community asset that will protect public health while fostering local economic development.

Why fund the New River Public Health Improvements Project?

By developing the New River Project, a great number of benefits will be realized to the citizens of the United States and the southwest region. These benefits include:

1. Public Health and Environment
   • Eliminating human exposure to toxic materials and disease organisms.
2. Community Development
   • Allowing productive land use in the area of the City of Calexico currently blighted or made unusable by the New River.
3. Security and River Safety
   • Eliminating the risks of drowning undocumented and eliminating the avenue of crossing the international United States border via the New River.

In addition to these benefits, a number of other factors have come into alignment that will assure that this will be a successful project:

1. The Project will improve and solidify our relationship with Mexico
   • Increase the Bi-National work ethic between the organizations of the United States and Mexico.
2. The Project will open doors to the economic future of the Southern California
   • The funding of this project will lay the groundwork for the awaited generation for future economic development and cross-border initiatives in the Calexico-Mexicali area such as shopping malls, parks and recreation attractions.
3. The Project will be compatible with future efforts to clean up the Calexico New River and downstream at the Salton Sea.

Project Overview

The specific features included in the Calexico New River Improvements Project have been identified and designed to meet a number of objectives:

• Providing immediate public health and environmental improvements in a manner that is compatible with longer-term pollution control and environmental improvements for the Calexico New River and Salton Sea.
• Preventing access to the Calexico New River in the immediate Calexico area, thereby eliminating direct human contact with the river.
• Providing an enhanced environment for community and economic development activities.
• Phasing project development so that those features that can be quickly permitted to move ahead independently of those features that will require a more lengthy review process.
• Identifying project features that can be developed locally, without the need for international negotiations.

Project Concept

The Project Concept has been in development for several years. During this time input was received from permitting agencies, local citizens, law enforcement agencies, the Immigration and Naturalization Service and the U.S. Border Patrol, local economic development agencies, environmental groups, and elected officials. As a result, a carefully thought out and balanced project concept has emerged that includes the following features:

• Providing trash screening and aeration about 400 feet downstream of the point where the New River enters the United States.
  • This will improve aesthetics while avoiding backwater effect across the United States/Mexico border.
• Isolating the river from public access by rerouting it through an enclosed channel as well as stabilizing the existing channel.
  • This will provide public health protection and address odor problems, limit access to the river, and cover potentially contaminated sediments in a manner that could be reversed when water conditions improve upstream in Mexico.
• Creating open space including walking and bicycle trails, and soccer and baseball fields.
  • This will provide the opportunity for “outdoor” experiences for individuals working and living in the area and make the area more attractive for businesses and cross-border initiatives and collabortion with fish and wildlife agencies.

Introduction

As currently conceived, the Project will include:

• Installing a trash rack about 400 feet downstream from the point of the United States/Mexican border to allow for tires and debris to be removed from the New River.
• Constructing an enclosed box culvert to convey Calexico New River flows from Mexico through properties that are currently zoned open space, commercial, and industrial and that are available to support future commercial activities.
• Stabilizing the existing Calexico New River channel to provide for the flow of reclaimed water and, when necessary, overflow of New River water during periods of unusually intense rainstorms.
• Open space improvements including plantings, walking and bicycling trails, soccer and baseball fields.

Development Activities

Will primarily involve site grading and excavation, construction of concrete structures, bank and streambed stabilization, installation of trash-rack equipment, and plantings and other open space improvements. Development activities for this phase will include full environmental review under the California Environmental Impact Report, and permitting. Permitting will include the need to obtain permits from the U.S. Army Corps of Engineers and may also necessitate EIS-level environmental review under NEPA. In that event, a joint CEQA/NEPA review will be conducted to expedite the Project. As a result of this process, modifications and refinements to the Project features may result.Project ComponentsThe following paragraphs provide general descriptions of the Project components as currently conceived.

1. Trash rack
   • To intercept trash and large debris, a trash rack structure will be installed at an oblique angle just before the inlet to the box culvert. The trash rack structure will consist of two self-cleaning (automated) trash racks. Material intercepted by the trash racks will be collected into containers by means of an electrically operated conveyor belt.
2. Box Culvert System
   1.  
      • The transition/diversion structure will be located just downstream from the first bridge over the river as it crosses the border in Calexico. This structure will transition from the trapezoidal New River channel into the rectangular box culvert. It also will include an emergency spillway, for overflow during high precipitation events. Immediately downstream from the emergency, the existing New River channel will be protected against erosion. A concrete wall and bulkhead gates, located upstream of the trash rack structure, will allow the closing of the one of the two box culvert sections when needed (e.g., for maintenance purposes).
   1.  
      • The box culvert is designed to transport Calexico New River water with flows during most conditions while still allowing for adequate freeboard. The box culvert will consist of two separate rectangular sections that will extend for the entire length of the alignment. The box culvert will be constructed of cast-in-place concrete. An asphalt covered bicycle trail will be constructed on top of the culvert. The box culvert alignment will parallel the southern bank of the existing Calexico New River channel and will then cross the river near Highway 98. The length of the alignment is about 16,100 feet. Due to topographic conditions and its proximity to the Calexico New River, three different trenches will be needed for the placement of the box culvert.
   • Transition/Diversion Structure
   • Box Culvert
3. Riverbed Stabilization
   • To stabilize the existing river channel, it will be covered with a geotextile liner and with riprap in selected areas to prevent erosion of accumulated sediments that may contain concentrations of certain contaminants that have been discharged to the river. Streambed stabilization measures will extend from the point on the river near the inlet to the box culvert downstream to the bridge on Highway 98. The modified and stabilized channel will allow for the low flow of reclaimed water from the wastewater treatment plant.
4. Open Space/ Habitat Improvements

To help mitigate the impact of the civil structures, the Project also includes a number of open space improvements. These include:

• Creating open space on the north side of the river. This area will be graded and hydro-seeded. Bike and pedestrian paths will be constructed through this area. Soccer fields and baseball fields could be constructed. Public restrooms will also be provided in this area.
• Creating another open space on the south side of the river. This area will be graded and hydro-seeded. Native (drought tolerant) trees will be planted along the box culvert alignment, which will be topped with asphalt for use as a bicycle trail.
• Removing non-native species to the west of the All American Canal siphon and replanting the area up from the river bank with drought tolerant native species.
• Helping support the creation of artificial and enhanced wetlands. These wetlands will likely be located downstream of Project facilities along the Calexico New River. In addition to habitat, the wetlands will provide some passive treatment of agriculture drainage to the river.

Funding Request Costs

The funding request for the Project is presented below:

• Engineering design
• CEQA/NEPA studies
• Inlet structure
• Trash rack
• Box culvert (enclosure)
• Open space habitat improvement
• Wetlands