Arroyo Colorado

Watershed Protection Plan Implementation

Project Overview

Scope of Work

Funding Source

Funding provided by the Texas Commission on Environmental Quality and EPA as part of a Clean Water Act Section 319(h) Grant.


This project addresses the tasks necessary for TCEQ, its partner agencies, and its contractors to facilitate implementation of the Arroyo Colorado Watershed Protection Plan (Arroyo WPP) to address low dissolved oxygen in the tidal segment of the Arroyo Colorado. The Arroyo Colorado WPP shall be completed under a previous Clean Water Act Section 319(h) project through Texas Sea Grant. Concurrent to WPP finalization, this project will begin facilitating its implementation.

Since assessments of water quality were first conducted by the state of Texas in the mid 1970s, the tidal segment of the Arroyo Colorado (segment 2201) has consistently failed to meet the state's water quality standards designed to protect aquatic life use in tidal streams of the state. Segment 2201 is again included in the most recent list of impaired water bodies of the state of Texas, the draft 2004 Texas Clean Water Act Section 303(d) List, because dissolved oxygen concentrations in the upper 8 miles of the segment are often lower than the criteria established to assure optimum conditions for aquatic life.

Extensive agricultural activity in the watershed and millions of gallons of treated, marginally treated, and, essentially untreated wastewater contribute to high levels of pollutants entering the Arroyo Colorado on a daily basis. In addition to high loadings of oxygen-demanding substances and nutrients, the Arroyo Colorado stream system has been physically modified extensively to convey storm water and wastewater produced within its watershed. The tidal segment of the Arroyo is also dredged for navigation from the intercoastal waterway in the Laguna Madre to the Port of Harlingen.

In 1998 the Texas Commission on Environmental Quality (TCEQ) initiated an effort to develop a TMDL for pollutants causing low dissolved oxygen (DO) in the tidal segment of the Arroyo Colorado.

The TMDL effort was completed in 2002. However, because of lingering uncertainty surrounding cause-and-effect relationships associated with the observed DO impairment, the TMDL analysis completed in 2002 was unable to support a quantitative, water quality target-based allocation of loadings of constituents associated with DO dynamics in the tidal segment of the Arroyo Colorado.

The Arroyo Colorado TMDL study completed in 2002 also concluded the following:

  1. DO dynamics in the Arroyo Colorado are highly influenced by physical characteristics of the stream (i.e. dredged tidal channel hydraulics)
  2. Load reductions necessary to comply with current DO criteria are not realistically achievable (i.e. the study found that a 90% reduction in loading would be necessary)
  3. There is need for further study to gain a better understanding of cause-and-effect relationships associated with the observed impairment and also to reduce uncertainty in the analysis.

The (2002) TMDL effort did not result in TCEQ adoption. However, as a direct result of this initial TMDL effort, TCEQ led efforts to develop a comprehensive strategy to address low DO in the tidal segment of the Arroyo Colorado. The strategy includes efforts to reduce pollutant loadings, improve aquatic habitat, and conduct additional monitoring and modeling for refinement of the existing TMDL analysis. Development of the Arroyo Colorado Watershed Protection Plan was a consensus-based effort initiated by a group of stakeholders with assistance from several state and federal agencies.

The stakeholder group associated with this project, the Arroyo Colorado Watershed Partnership, was formed in Weslaco, Texas in July, 2003 and includes members of the previous Arroyo Colorado TMDL Stakeholder Committee and the Arroyo Colorado TMDL Science and Technical Advisory Committee, both of which were formed in 1998.

The Arroyo Colorado Watershed Partnership, in close cooperation with TCEQ, formed the Arroyo Colorado Watershed Steering Committee and five separate work groups to provide direction for the Partnership and to address and develop five major components of the comprehensive Arroyo Colorado Watershed Protection Plan. These components were identified as a result of TMDL development efforts in the Arroyo Colorado and are as follows:

  • Wastewater Infrastructure
  • Agricultural Issues
  • Habitat Restoration
  • Further Study/ Refinement of TMDL Analysis
  • Outreach and Education

The five workgroups created to address issues associated with each of the components described above were responsible for developing recommendations for improving water quality, including reducing current pollutant loadings, restoring/improving aquatic habitat, increasing public awareness and education, and conducting additional monitoring and research. Recommendations provided by the workgroups were integrated into the comprehensive Watershed Protection Plan for the Arroyo Colorado.

Goals and Objectives

Recognizing the need to assist and track implementation of the WPP, assess effectiveness of the WPP in improving water quality, continue facilitation of the Arroyo Colorado Watershed Steering Committee, provide necessary outreach and education, and seek funding opportunities to ensure implementation of the WPP, TCEQ and Arroyo Colorado Watershed Steering Committee will fund the position of Watershed Coordinator and Grant Writer/Water Quality Analyst for the Arroyo Colorado watershed.

This project will: 1) fund a watershed coordinator and grant writer, 2) facilitate, coordinate, and track actual implementation measures described in the WPP, 3) continue to identify additional feasible measures for reducing pollutant loading to the Arroyo Colorado, 4) identify and seek additional funding to continue watershed protection efforts in the Arroyo Colorado, 5) link partners and projects to available funding sources, 6) sponsor local workshops with state, local, and regional agencies and organizations, and 7) publicize and build awareness of the watershed improvement efforts and bolster local support and participation in these efforts. This project will also analyze all available water quality monitoring data to examine and document changes in pollutant loading, water quality, and habitat during the implementation of the Arroyo Colorado WPP and continued outreach and education efforts.

Facilitation, coordination and management of the Arroyo Colorado Watershed Steering Committee and implementation of the WPP will entail a substantial commitment of time and resources. The Watershed Coordinator will provide a single point of contact for activities of the work groups, manage and track work group activities, facilitate information exchange among participants, and, ultimately, ensure implementation of the WPP for the Arroyo Colorado. The Arroyo Colorado Watershed Coordinator will be responsible for coordinating management of the Steering Committee and facilitating implementation of the WPP by providing the extensive outreach and education activities that will be needed to successfully achieve successful implementation.

The Grant Writer/Water Quality Analyst will identify and help acquire additional resources for use by the Watershed Steering Committee, Partnership, and individual work groups, to implement the WPP. The Grant Writer/Water Quality Analyst will also compile water quality data collected throughout the Arroyo and periodically assess it for water quality trends and improvements.

Project Tasks

Task 1: Project Administration

Objective: TWRI will effectively coordinate and monitor all technical and financial activities performed under this contract, prepare progress reports and a final report, and maintain project files and data. TWRI will be responsible for hiring and supervision of all project personnel. And TWRI will ensure regular meetings and communication occur among project participants and granting agency.

Task 2: Steering Committee and Work Group Facilitation

Objective: The ACWC will provide a structure/encouragement for continued stakeholder participation and involvement; arrange and facilitate Arroyo Colorado Watershed Steering Committee meetings; ensure activities of work groups are consistent with goals and objectives of the Watershed Steering Committee and will advance the goal of implementing individual components of the Watershed Protection Plan. The ACWC will also document all Steering Committee and work group activities.

Task 3: Facilitate Watershed Protection Plan Implementation

Objective: The ACWC will facilitate implementation of the Watershed Protection Plan through outreach and education activities in the Arroyo Colorado watershed, and other activities designed to promote private and public support for the implementation of the WPP. The ACWC will identify local, regional and national groups and agencies planning, or engaging in activities with goals similar to those of the Arroyo Colorado Partnership and, to the highest extent practicable, coordinate and integrate the efforts of the Arroyo Colorado Partnership with the activities of the groups identified.

Task 4: Resource Identification and Grant Writing

Objective: Identify potential state, federal, non-profit, and private sector resources useful to the Watershed Partnership for implementation of the Watershed Protection Plan and assist individual work groups in resource identification and grant writing for activities and projects associated with individual work group goals.

Task 5: Data Gathering and Analysis to Assess Effects of Water Quality Protection Plan

Objective: The ACGC will assemble and maintain a data clearinghouse for all data collected in the Arroyo and from that data, evaluate changes in BOD, TSS, fecal bacteria, and nutrient loading to Segments 2201 and 2202 of the Arroyo Colorado.

Project Personnel
Jaime Flores
Watershed Coordinator, AgriLife Extension Service
Megan Meier
Grant Writer/Data Analyst, AgriLife Research
Ruben Saldana
District Extension Administrator, District 12
Allen Berthold
Project Manager, TWRI
Allen Berthold
Project Manager, TWRI