Project Work Plan

Purpose

This project aims to restore water quality within Village Creek and to protect the water quality within Lake Arlington and its watershed through the development and implementation of a watershed protection plan (WPP).

 

Problem/Need Statement

Lake Arlington serves as a drinking water source to over 500,000 people in the DFW metroplex. Village Creek, Lake Arlington’s main tributary,  is listed on TCEQ’s 2012 Texas Water Quality Inventory-303(d) List as impaired for bacteria (first listed in 2010) and several portions of Lake Arlington are listed on TCEQ’s 2012 Water Quality Inventory—Water Bodies with Concerns for Use Attainment and Screening Levels for chlorophyll-a and nitrate. Past studies conducted within the watershed and rapid development indicate that water quality has and will continue to be negatively affected unless more vigorous management measures are put in place.

 

Watershed stakeholders are active and have demonstrated their concern about water quality issues within the watershed through several past projects. The Lake Arlington Master Plan (LAMP) is one of these projects. LAMP included water quality modeling for nutrients, sediment, and fecal coliform; it also illustrated how the various forms of development may impact water supply and quality. Best Management Practices (BMPs) to mitigate impacts from future development in the watershed (rather than existing impairments) were suggested based on the results of a screening-level water-quality modeling effort. Since being adopted by Arlington’s City Council in April 2011, many development standards from the LAMP have been codified into Arlington ordinances. LAMP was also adopted by City of Fort Worth City Council. During the development of the LAMP, water quality samples were collected and analyzed and a PLOAD model was developed. The results of the sampling and modeling effort identified nutrients and chlorophyll a as important parameters of concern. While well-suited to the objectives of the LAMP, the sampling and modeling performed is not of sufficient quantity and specificity to allow load reductions to be calculated for existing impairments. In addition the LAMP served to aggregate a significant amount of information on land use and watershed activities that can be used to develop a WPP. For instance, numerous potential sources of pollution from salvage yards were identified in the immediate upstream floodplain of the reservoir. The LAMP puts at TRA and the Stakeholder’s disposal a wealth of information that can be used to develop the WPP.

 

As part of the process for developing LAMP, stakeholders were identified and stakeholder participation was elicited. The establishment of bimonthly meetings of the various stakeholders within Lake Arlington’s watershed to discuss opportunities to collaborate on watershed protection initiatives has been ongoing since 2011, and was instrumental in creating this grant application  An assessment of the LAMP was undertaken in May 2012 by these stakeholders to identify and prioritize the suggested projects.

 

The proposed project seeks to build upon the LAMP and other initiatives in the watershed such as the North Central Texas Council of Governments Greenprinting and the City of Kennedale’s Village Creek Master Plan by developing an effective WPP that will identify and provide the groundwork for implementation of strategies to address the current water quality problems of bacteria in Village Creek, nutrients and chlorophyll a in Lake Arlington and potentially other constituents of concern identified during the project and sampling activities. The watershed stakeholders have demonstrated a long-term commitment towards this goal and have asked the Trinity River Authority to work with them to produce a WPP. The WPP will not only provide specific direction towards meeting current challenges, but will also provide a holistic framework for protecting water quality as the watershed develops.

 

Project Goals

The ultimate goals of this project are to restore and protect water quality in the Lake Arlington watershed through the development of a Lake Arlington/Village Creek WPP. The plan will meet EPA’s Nine Key Elements for Watershed-Based Plans as explained in the “Handbook for Developing Watershed Plans to Restore and Protect Our Waters,” (EPA 841-B-08-002) (hereafter referred to as the EPA Handbook)  and provided in the EPA 2014 guidelines. This WPP will analyze, compile, and summarize technical information in order to advise the stakeholder group on appropriate watershed best management practices, proposing avenues of implementation in order to restore and protect the water quality of Lake Arlington and Village Creek. Specifically, reduce E. coli concentrations to below the standard of 126 MPN geometric mean and 394 MPN single grab sample maximum established for segment 828A.

 

The success of any watershed-level project relies on the involvement of its stakeholders and their willingness to implement the plan. Efforts will be made to expand and create an organizational structure for the existing stakeholder group, which will serve as a decision-making body throughout the watershed planning process and pursue implementation of strategies after the WPP is developed.

 

While much data has been collected through past projects to characterize the watershed, additional, targeted information is needed in order to create a solid plan for implementation. Specifically, sources, or areas of likely E. coli contribution need to be identified. Routine monitoring conducted heretofore was conducted as a screening tool and as such is of insufficient spatial and temporal coverage for source identification. This project will conduct targeted water quality sampling, analysis and load calculation (particularly for E. coli and nutrients) in order to obtain the technical information necessary to build the WPP. This project will also evaluate annual and seasonal trends, spatial patterns, hydrologic characteristics (i.e. flow characterization), and other relationship patterns that will help identify how and when E. coli and other pollutants are entering the system. Additional information such as land use, soil types, locations of onsite sewage facilities (OSSFs), etc. will be obtained from the existing Watershed Master Plan and acquired from other sources (e.g. stakeholders) as needed to supply bacteria loading information to a functioning Spatially Explicit Load Enrichment Calculation Tool (SELECT) which will assist stakeholders with identification of potential bacteria sources throughout the watershed.

 

Previous projects within the watershed have been conducted independently of each other, with individual goals and results created by different stakeholder groups. This project will aggregate the information obtained through past projects with new data to create a holistic management plan for the Lake Arlington/Village Creek watershed, connecting stakeholders and offering them an integrated perspective of the watershed. A key source of information will be the LAMP which aggregated data on water quality, land use, runoff and areas of potential pollutant contribution.

 

General Project Description

The project will result in the development of a Lake Arlington/Village Creek WPP which will meet EPA’s Nine Key Elements for Watershed-Based Plans as provided in the EPA 2014 guidelines and provides quantified objectives for water quality improvement through identified and prioritized watershed management strategies. The watershed planning process will involve the expansion and enhancement of the existing stakeholder group, identifying roles for various levels of involvement, and defining an organizational structure. Once this project begins, stakeholder meetings will be focused on the iterative steps that will ultimately develop a WPP with specific targets and strategies for water quality improvements. Although the existing group is engaged and committed (as evidenced by their request to have TRA apply for this grant and the development of a watershed master plan), every effort will be made to keep them involved and capitalize on their knowledge of the watershed. In so doing, the WPP will have partners who understand the costs, objectives, and benefits of selected watershed management projects.

 

The development of this project is based on the understanding and interpretation of 1) the EPA guidelines for CWA Section 319 grant funds released in April 2013, Nonpoint Source Program and Grants Guidelines for States and Territories (hereafter referred to as the EPA 2013 Guidelines), and 2) the EPA. The project is designed to ensure the project is consistent with and satisfies the EPA’s 9 Key Elements for Watershed-based Plans.

 

In addition to the extensive work performed during the development of the WPP, a preliminary review of the watershed based upon a limited dataset and evaluation of aerial imagery has been performed in preparation for this application. This analysis provided insight into the nature of the watershed and what a source identification sampling plan might entail. Based upon this work, it was determined that nine sites would be sufficient to provide spatial coverage of the watershed. After initial stakeholder consultation, it was determined that two additional sites would be added, for a total of eleven sites. These sites will be monitored on a routine, bi-monthly schedule, yielding six samples per site. It was further determined that water quality data would need to be obtained for different seasons and flow conditions. Accordingly, a total of six flow-targeted monitoring events per site are also proposed, for a total of twelve sampling events. Although it is expected that one flow-targeted event will occur in the two-month period between each routine event, the timing of these events will be refined through close observation of weather patterns for precipitation events, more detailed evaluations of historical data, and through stakeholder input regarding known or suspected areas of pollution contribution as well as further analyses of geospatial datasets. The goal of the project is to collect data across the range of instream flow conditions that take place during the sampling period.

 

The results of the source identification monitoring and historical data analyses, along with significant stakeholder input, will be used to develop load duration curves (LDCs) to quantify loadings of E. coli, NO2, NO3, TKN, TP, OP and other water quality parameters of importance to the stakeholder group. This information will then be used to quantify load reduction targets and appropriate BMPs. The WPP will encapsulate all of this information and provide a prioritization with recommended best management practices and routine monitoring to document improvement and ensure protection of water quality in the watershed.