Funding Source
Funding provided by General Land Office as part of the Costal
Management Program.
Project Description
Maintaining and protecting the water quality of the Lower Laguna
Madre, an important nursery for fish, shrimp and crab and a popular
site for recreational fishing and boating, is imperative for the
health of the Texas coast. However, the low dissolved oxygen (DO)
concentrations in the Arroyo Colorado, the primary source of
freshwater for the Lower Laguna Madre, have killed millions of fish
over the past few decades. Most of these fish kills occurred in the
tidal segment of the Arroyo, which directly flows into the Lower
Laguna Madre. To address the DO impairment, the Arroyo Colorado
Watershed Partnership (Partnership) developed the Arroyo Colorado
Watershed Protection Plan (WPP), a comprehensive watershed-based
strategy to improve water quality and aquatic and riparian habitat
in the Arroyo Colorado. One of the top strategies for water quality
improvement identified in the WPP is the construction of wetlands
for removal of nutrients. Therefore, the Port of Harlingen and the
Texas Water Resources Institute (TWRI) will construct a wetland to
remove nutrients from spoils dredged from the turning basin at the
Port of Harlingen, Texas.
The Port of Harlingen is located in the heart of the impaired
tidal segment of the Arroyo Colorado, which is classified by the
Texas Commission on Environmental Quality as the segment between
the confluence with Laguna Madre in Cameron/Willacy County to a
point 100 meters (110 yards) downstream of Cemetery Road in Cameron
County. This part of the water body is also defined as a coastal
natural resource area (CNRA) and a coastal wetland in the Coastal
Coordination Act. The location of the wetland is on an
approximately 35 acre site where dredge spoils from the turning
basin were previously dumped downstream of the Port of Harlingen on
the northwestern bank of the Arroyo Colorado. By impacting this key
location within the Arroyo Colorado, the resulting water quality
improvements will positively affect the water quality within the
Lower Laguna Madre maintaining its health as a vital coastal
nursery and ecological and economic resource.
Funding will address two major funding categories and goals
within the Coastal Management Program: water quality and quantity
improvements and enhancement of critical areas. Water quality
issues associated with the Arroyo Colorado and the Lower Laguna
Madre will be addressed through the construction of an approximate
35-acre wetland that will be designed and built to protect critical
habitat and provide nutrient removal from dredge spoils from the
turning basin from the Port of Harlingen. The spoils contain
nutrients from two sources: 1) nonpoint source pollution during
Port activities (loading, unloading, stormwater runoff) and 2)
detachment from upstream sediment that settles out of the water
column in the turning basin (a wider, deeper segment of the stream
that has slower flow). By removing these nutrients, the spoils can
be purchased and used as beneficial amendments in other areas of
the watershed, which will provide revenue for sustaining the
sediment basin and wetland system. In addition to improving water
quality
Task 1: Texas A&M AgriLife, TWRI will
effectively coordinate and monitor all technical and financial
activities performed under this contract, prepare progress reports,
and maintain project files and data. TWRI will be responsible for
hiring and supervision of all project personnel.
Task 1 Deliverable and Timeline.
- Project Oversight - TWRI will provide technical and fiscal
oversight to ensure Tasks and Deliverables are acceptable and
completed as scheduled and within budget.
- Fiscal/invoicing - Texas AgriLife Research will submit
reimbursement forms per the schedule established/requested by the
GLO.
- Regular Meetings - To facilitate good communication between
project participants, a quarterly meeting or teleconference will be
scheduled and hosted by TWRI.
- Quarterly progress reports - TWRI, with the assistance of the
Arroyo Colorado Watershed Coordinator (ACWC), will submit progress
reports to GLO quarterly. The reports will include the status of
deliverables for each Task and a narrative description of
activities for each task outlined in this Scope of Work in Progress
Report format.
- Final Report - TWRI, with assistance of the ACWC, will provide
GLO with a comprehensive report on the activities during the course
of this project. March 2011.
Task 2: An ecological assessment will be
conducted to determine appropriate locations for wetland/sediment
basins. Efforts will be made to preserve natural habitat where
possible and incorporate natural components of the landscape.
Therefore, plants will be identified and mapped in order to ensure
that native, threatened, and endangered plants are preserved on the
site and incorporated into the design. The assessment will also
delineate wetlands on the property and identify areas that are
prone to erosion and thus should be avoided during
construction.
Task 2 Deliverable and Timeline.
- A coordination meeting with Port of Harlingen staff, Alan
Plummer Associates, Inc (APAI)., TWRI, and University of Texas at
Brownsville (UTB) faculty (to be conducted by conference call) will
be held to discuss goals and objectives of studies to be
conducted.
- Ecological Assessment - The UTB will identify native and
non-native flora and fauna, delineate wetland areas, determine soil
types and erosion concerns on the approximately 35 acre site
located on the northwestern bank of Arroyo Colorado at the Port of
Harlingen, Texas.
- Report and map - The UTB will provide a final report and GIS
map to APAI and the GLO that includes species identified and
highlights which areas should be avoided and which should be
incorporated into the design of the sedimentation basins and
treatment wetlands. January 2010
- Permit Requirement Coordination - After review of reports
prepared by UTB documenting ecological studies, APAI will
coordinate with state and federal agencies regarding determination
of new permits required for construction of a system of
sedimentation basins and wetlands to polish decant water from the
dredging operations as well as associated amenities including
conveyance of outflows back to the Arroyo Colorado. It is
anticipated that coordination with U.S. Army Corps of Engineers'
Operations Division, Engineering Division, as well as Regulatory
Branch may require an on-site meeting with the representatives as
well as representatives from the coordinating review agencies
including the GLO, Texas Parks and Wildlife Department, U.S. Fish
and Wildlife Service, U.S. Environmental Protection Agency, Texas
Commission on Environmental Quality, and potentially others. March
2011
Task 3: Alan Plummer Associates, Inc. (APAI) in
cooperation with the Port of Harlingen will analyze the following
data for the proposed project site as part of the technical review
and analysis. APAI will be responsible for gathering listed
data:
- Hydrological data
- Soils data
- Previous geotechnical report(s), if any, for the
proposed project area
- Available topographic data
- Environmental and/or ecological reports for the
proposed wetland site
Task 3 Deliverable and Timeline.
- A coordination meeting with Port of Harlingen Staff, APAI, and
TWRI will be held to discuss goals and objectives of analysis to be
conducted (via conference call).
- Survey - The Port of Harlingen will have the 35 acre site
surveyed, with guidance from APAI, on the criteria for the survey
(density of shots, format, etc.). January 2010
- Conceptual layout of the wetland - Once the surveying services
have been completed, APAI will review the survey and other data
provided by the Port of Harlingen and UTB, and will develop a
conceptual layout of the wetland/sediment basin. APAI will provide
three copies of a draft conceptual plan to the Port of Harlingen
Staff and project team partners to review approximately one week in
advance of a meeting to discuss and finalize the conceptual design
of the wetland/sediment basin. APAI will then travel to the site
and meet with Port of Harlingen staff and project team partners on
site for project team partners to verify the selected site on the
ground. August 2010
- Conceptual Design Report - APAI will prepare a Draft Conceptual
Design Report documenting conceptual layout of the Project and the
data gathered in Subtask 3.1. APAI will provide three copies of the
draft Conceptual Design Report to the Port of Harlingen and project
team partners for comment. APAI will finalize the Conceptual Design
Report based on comments received. The Conceptual Design Report
will be used in future Project phases (securing permits, etc.).
December 2010