1.3.5 conductor stringing
Post on 14-May-2022
21 Views
Preview:
TRANSCRIPT
n anNnM 0
1.3.4 Support Structure Assembly and Erection
Foundations for the lattice steel towers will be completed before erecting the structures.
Four holes will be augered into the ground (one hole per tower footing) at each tower
location as illustrated in Figure 1-2. The holes will be filled with steel-reinforced
concrete to form piers. Stub angles for anchoring the tower will be embedded at the
center of the concrete foundations.
Each lattice steel tower will be assembled on the ground near its designed location.
Tower assemblies will then be lifted by crane and aligned with and attached to
foundation stub angles with structure arms oriented perpendicular to the transmission
line centerline. For angle structures, towers will be set with structure arms oriented on
the angle bisector.
Foundations for the pole structures as illustrated in Figure 1-3 will be completed before
erecting the structures. One hole will be augered into the ground at each structure
location; an anchor bolt cage will be placed in addition to steel rebar to reinforce the
foundation and the holes will then be filled with concrete. Depth and diameter of thefoundation will vary depending on the design of the structure specific to that location.
1.3.5 Conductor Stringing
Once a series of structures have been erected along the transmission line centerline, the
conductor stringing phase can begin. Specialized equipment will be attached to properly
support and protect the conductor during the pulling, tensioning, and sagging operations.
Once conductors and shield wire are in place and tension and sag have been verified,
conductor and shield wire hardware is installed at each suspension point to maintain
conductor position. Conductor stringing continues until the transmission line
construction is complete. All construction equipment will be removed. All temporary
culverts and environmental controls previously installed will be removed.
haittAssociates Page 1-11
50
0 nnonn ;: n
THIS PAGE LEFT BLANK INTENTIONALLY
rage i-u Halff Associates
51
n NnanE n
2.0 ROUTE SELECTION METHODOLOGY
The objective of this study is to identify and evaluate alternative transmission line routes
for Oncor's proposed New Bethel 345 kV Transmission Line Project. Throughout this
report, the terms "environment" or "environmental" are used to include the human
environment as well as the natural environment. Halff utilized a comprehensive
transmission line routing methodology to identify and evaluate alternative transmission
line routes. Potential routes were identified and evaluated in accordance with Section
37.056(c)(4)(A)-(D) of the Texas Utilities Code, PUCT Substantive Rules Section
25.101, including the PUCT policy of prudent avoidance, PUCT Procedural Rules
Section 22.52(a)(4), and the PUCT CCN Application Form for a Proposed Transmission
Line.
The following subsections provide a description of the route selection methodology,
including study area delineation, data collection, constraints mapping, identification of
preliminary alternative routes, public involvement program, adjustment of preliminary
alternative routes following field review and public participation meetings, and evaluation
of the alternative routes.
2.1 Study Area Delineation
The first step in the identification of alternative routes was to define a study area. This
area needed to encompass potential termination points (e.g. the New Bethel Switching
Station in Anderson County), and include an area large enough that a reasonable
number of forward progressing geographically diverse alternative routes could be
identified. The purpose of delineating the study area for the proposed project was to
establish boundaries and limits for the information gathering process (i.e., identifying
environmental and land use constraints). The delineation of the study area also allowed
Halff to focus its evaluation within a specific area.
Halff reviewed U.S. Geological Survey (USGS) 1:24,000 scale topographic maps
(USGS, 1960 - 1984) and U.S. Department of Agriculture (USDA) aerial photography
(USDA, 2014), and conducted site reconnaissance to develop and refine the study area
boundary for this project. Halff located and depicted the project endpoints on the various
maps and identified major features in the general study area such as United States
Halff Associates Page 2-1
52
0 MnENn n
Highway (US) 84, US 287, State Highway (SH) 31, SH 274, Richland Chambers
Reservoir, Fairfield Lake, Fairfield State Park, the Trinity River, Gus Engling Wildlife
Management Area (WMA), Richland Creek WMA, Big Brown Power Plant facility (Big
Brown SES) and various cities, towns, and communities located in the vicinity. Figure
2-1 shows the study area boundary Halff delineated overlain on aerial photography and
general constraints as a result of the above-described process.
Figure 2-2 provides a more detailed map of the study area. The study area is a
rectangular shape with a northern boundary (approximately 16 miles in length) aligned in
a west to east direction generally between the City of Trinidad and the City of Athens.
From the City of Trinidad in Navarro County, the study area boundary extends south
approximately 33 miles to a point south of the City of Fairfield, representing the longer
axis. The study area boundary then extends east for approximately 16 miles roughly
parallel to the northern boundary. From the southeastern corner, the study boundary
extends north approximately 33 miles paralleling the western boundary to a point south
of the City of Athens.
Nage 2-2 Halff Associates
53
n anonn n
Halff Associates Page 2-3
54
Figure 2-1. Project Area Map
n^n^ n
THIS PAGE LEFT BLANK INTENTIONALLY
Page 2-4 Halff Associates
55
^^Q }Q
w
Z Z ^ W =^a
^r y
o w^ o
Q WN p ^ z
Q0
_
Za
00 Z w Q w o
W^ oz
a o<
m ^ Z ^
- W
0oQ wFn
U
^^
C/) Ofa a
WW W
0^ a
h'on
= Q w Z^}
} ~ c ^(D a Ix o
^ ^ Z Z 0 U) a^ D
_
Z°Z
K°
-j x > y =
LL Q a<
wr (1)0 _
<vi
<^
Z
^
^ ^
O
H
XyN
L. _ _--- L7J o
^
U>
NI
I m
'LL
^ LLI ^ ....i? QIw +
y^ ONE
®^^
o
TJJ
Z0HZWHZ_
Z
J
HLLWJ
WU
CLCOx^
0 nnEnn n
2.2 Data Collection
2.2.1 Solicitation of Information from Local, State, and Federal Officials and
Agencies
Once the study area boundary was identified, Halff initiated a variety of data collection
activities. One of the first such activities was the development of a list of officials to
whom a consultation letter regarding the proposed project would be mailed. The
purpose of the consultation letters was to inform the various officials and agencies of the
proposed project and give them the opportunity to provide information they may have
regarding the study area. Halff utilized the North Central Texas Council of
Governments, Heart of Texas Council of Governments, East Texas Council of
Governments, and the Texas Municipal League websites, as well as confirmation via
telephone calls, to identify incorporated cities and towns within the study area, and
identify the local officials within each city or town. State and federal agencies that may
have potential permitting requirements for or other interests in the proposed project were
also identified. Correspondence was sent to the following federal or state agencies, and
local officials and departments. Copies of all correspondence to and from these
agencies are included in Appendix A.
FEDERAL AGENCIES
• Federal Aviation Administration (FAA) - Southwest Division
• Federal Emergency Management Agency (FEMA)
• Natural Resources Conservation Service (NRCS)
• U.S. Army Corps of Engineers (USACE) - Fort Worth District
• U.S. Department of Defense
• U.S. Fish and Wildlife Service (USFWS) - Arlington Field Office, Austin Field
Office, and Houston Field Office
STATE AGENCIES
• Railroad Commission of Texas (RRC)
• Texas Archeological Research Laboratory (TARL)
• Texas Department of Criminal Justice, Coffield Unit
• Texas Department of Transportation (TxDOT) - Aviation Division, Bryan District,
Dallas District, Office of Environmental Affairs, and Tyler District
Halff Associates Page 2-7
58
^:, nnNnn =s
• Texas General Land Office (GLO)
• Texas Historical Commission (THC)
• Texas Parks and Wildlife Department (TPWD)
• Texas Water Development Board (TWDB)
REGIONAL OR INDEPENDENT AGENCIES
• East Texas Council of Governments
• Heart of Texas Council of Governments
• North Central Texas Council of Governments
• Tarrant Regional Water District (TRWD)
• Trinity River Authority - Anderson, Freestone, Henderson, Navarro County
Directors
• Upper Neches River Municipal Water Authority
COUNTY AGENCIES
• Texas Farm Bureau - Anderson County, Freestone County, Henderson County,
and Navarro County
• County Historical Commission - Anderson County, Freestone County,
Henderson County, and Navarro County
• Anderson County Officials (County Judge, County Commissioners)
• Freestone County Officials (County Judge, County Commissioners)
• Henderson County Officials (County Judge, County Commissioners)
• Navarro County Officials (County Judge, County Commissioners)
CITY AGENCIES
(includes council members, city staff, and economic development boards)
• City of Athens
• City of Fairfield
• City of Goodlow
• City of Kerens
• City of Malakoff
• City of Trinidad
• City of Trinidad Economic Development Board
Page 2-8 Halff Associates
59
0 fnO!0 n
SCHOOL DISTRICTS
• Athens Independent School District (ISD)
• Cayuga ISD
• Cross Roads ISD
• Fairfield ISD
• Kerens ISD
• LaPoynor ISD
• Malakoff ISD
• Palestine ISD
• Trinidad ISD
Other data collection activities included a file and record review of various regulatory
agency databases, a review of published literature, and review of a variety of maps,
including recent aerial photography (USDA, 2014), seamless USGS topographic maps
(National Geographic Society [NGS], 2013), county highway maps, and county appraisal
district land parcel boundary maps. Findings of the data collection activities are detailed
in Section 3.0.
2.2.2 Reconnaissance Surveys
Halff conducted multiple reconnaissance surveys of the study area to develop and
confirm the findings of the above-mentioned research and data collection activities and
to identify existing conditions or constraints that may not have been previously noted.
Results from the site visits were also utilized to assist in the route selection process.
Ground reconnaissance surveys were conducted by visual observations of study area
characteristics from public roads and public ROW located within the study area.
Reconnaissance survey information was noted in the field and geographically referenced
to digital aerial photography base maps. Reconnaissance surveys (including aerial fly-
overs) were conducted on the following dates:
• July 18, 2013 • April 8, 2014• September 18, 2013 • April 23, 2014• September 19, 2013 • June 11, 2014• October 16, 2013 • March 6, 2015
• April 14, 2015
Halff Associates Page 2-9
60
^ ^^^NW N
The data collection effort, although concentrated in the early stages of the proposed
project, continued up to the point of final development of alternative routes. Results of
the various data collection activities (e.g., solicitation of information from local, state, and
federal officials and agencies, file/record review, and visual reconnaissance surveys) are
included in Section 3.0 and Section 7.0 of this report.
2.3 Constraints Mapping
The data and information collected from the activities outlined above were used to
develop an environmental and land use constraints map. The constraints map, public
maps, aerial photography, reconnaissance surveys, and other research were used to
identify and select potential preliminary alternative routes within the study area.
Locations of avoidance areas and opportunity areas within the study area were located
and considered during transmission line route identification. Halff sought alternative
routes that minimized potential impacts to "avoidance areas".
Avoidance areas could require special considerations or mitigation measures, even
though there is no law or regulation that would prohibit the crossing by a transmission
line. A few examples of avoidance areas would be public parks or residential
developments. Avoidance areas vary in significance depending upon the type of
constraint. For example, an archaeological site may be considered a low or medium
avoidance area as actual disturbance of the site could likely be avoided by spanning the
transmission line over the site.
Once the avoidance areas are identified and mapped as routing constraints, the
remaining areas are considered opportunity areas. Opportunity areas are considered to
be low-impact areas, or those areas with a lower likelihood of containing existing natural
or human resources that could be negatively affected by a transmission line.
2.4 Identification of Preliminary Alternative Route Links
Upon completion of initial data collection activities and the constraint mapping process,
the next step in the process was to identify preliminary alternative route links to connect
the New Bethel Switching Station to potential endpoints. Halff utilized the following
sources of information to identify the preliminary alternative routes:
Page 2-10 Halff Associates
61
N Entn0 t
• input received from the various meetings and correspondence with agencies and
local officials, as described in Section 2.2.1;
• results from the visual reconnaissance surveys of the study area;
• review of recent aerial photography;
• findings of various data collection activities;
• environmental and land use constraints map;
• apparent property boundaries;
• existing compatible corridors;
• locations of existing developments; and
• other information.
Preliminary alternative route links were identified in accordance with Section
37.056(c)(4)(A)-(D) of the Texas Utilities Code and PUCT Substantive Rules Section
25.101 including the PUCT policy of prudent avoidance. The intent was to identify an
adequate number of geographically diverse alternative routes which were
environmentally acceptable considering such factors as the following: community values;
park and recreation areas; historical and aesthetic values; vegetation, wildlife, and water
resources; environmental quality; length of route parallel to or utilizing existing
compatible corridors; length of route parallel to apparent property boundaries; and the
PUCT policy of prudent avoidance. In addition, Oncor provided engineering guidance
relating to paralleling existing compatible corridors in the study area and setback
guidelines for oil and gas wells and wind turbines. The preliminary alternative route links
identified by Halff were then presented at open house public participation meetings. A
more detailed discussion of the development of alternative routes is presented in
Section 4.0.
2.5 Public Involvement Program
Once the preliminary alternative routes were identified, a series of public participation
meetings were held. The first set of public participation meetings was held November 19
and November 21, 2013 from 4:00 P.M. to 8:00 P.M. at Cross Roads High School and
Cayuga High School campuses, respectively. A second set of public participation
meetings was held February 18 and February 20, 2014 from 4:00 P.M. to 8:00 P.M. at
Fairfield High School and Cross Roads High School campuses, respectively.
Halif Associates Page 2-11
62
0 nnNn0 n
The purpose of the public participation meetings was to solicit comments and input from
residents, landowners, public officials, and other interested parties concerning the
proposed project, preliminary alternative routes, and the overall transmission line routingprocess, and to:
• promote a better understanding of the proposed project including the need,
purpose, potential benefits, potential impacts, and the CCN certification process;
• inform the public with regard to the routing process, schedule, and the decision-
making process; and
• identify the values and concerns of the public and community leaders.
Oncor mailed a written notice of the public participation meetings to owners of property
within 500 feet of the centerline of the preliminary alternative routes. Notices were also
mailed to local officials and state and federal regulatory agencies. In addition,
advertisements were published in local newspapers announcing the location, time, and
purpose of the meetings. A summary of the newspapers in which public meeting notices
were published and the dates of publication are shown in Table 2-1, and a copy of thenotices can be found in Appendix B.
Table 2-1. Newspapers and Publication Dates for Notices of Public Participation
Meetings.Nnvpmhar 9n13 Mnn+G.,.,^
: Newspaper t Y Publication DateThe Palestine Herald Anderson November 15 and 18 2013Malakoff News Henderson
,November 15 2013
Athens Dail Review Henderson,
November 15 and 19, 2013
Februarv 201d Maptir,r,a
Newspaper County Publication DatePalestine Herald Press Anderson February 11 and 18 2014Fairfield Freestone County Times Freestone
,February 11 and 18 2014Fairfield Recorder Freestone
,February 13 and 20 2014Malakoff News Henderson
,Februa 14 2014
Athens Dail Review Henderson,
Februa 11 and 18, 2014
At the public participation meetings, Oncor and Halff set up information stations in the
meeting rooms. Each station was devoted to a particular aspect of the proposed project
and was staffed by Oncor, ML&M Realty Advisors, LLC (a land and title research firm
age &i 1Halff Associates
63
O ' snann n
contracted by Oncor), and/or Halff representatives. Each station had maps, illustrations,
photographs, and/or text explaining each particular topic. Interested citizens and
property owners were encouraged to visit each station so that the entire project process
could be explained in the general sequence of project development. The information
station format is advantageous because it allows attendees a chance to receive the
information in a relaxed manner and allows them to focus on their particular area of
interest and ask specific questions. Furthermore, the one-on-one discussions with
Oncor, Halff, and the other representatives encouraged more interaction from those who
might be hesitant to speak out in a speaker/audience forum.
Upon entering, visitors were asked to sign in and were handed an information packet
including an explanation of the proposed project, a map of preliminary alternative
transmission line route links, and a questionnaire. The information packet also included
answers to frequently asked questions, a drawing of the proposed typical transmission
tower, and a flow chart that detailed the CCN certification process for new transmission
lines. The questionnaire solicited comments on the proposed project as well as an
evaluation of the information presented at the open house meeting. Copies of the
information packet and questionnaire can be found in Appendix B.
Halff reviewed and evaluated the responses to the questionnaire that were submitted at
the meetings and by mail following the meetings. Attendee comments were considered
and factored into the overall evaluation of the alternative routes.
2.6 Adjustments of Alternative Route Links Following the Open House Public
Participation Meetings
Following the November 2013 public participation meetings, modifications were made to
a number of the links presented at the public meetings and numerous new links within
an expanded study area were added. The modifications, expansion of the study area,
and addition of links were the result of input from meeting attendees, the acquisition of
more detailed property boundary maps, and Halff's further evaluation of the preliminary
alternative route links. This second set of preliminary alternatives was presented at the
February 2014 public meetings. Following these public meetings, modifications were
similarly made to several route links and numerous route links were deleted from the set
haitt AssociatesPage 2-13
64
0 n
^ n
of preliminary alternatives. The new route links and modified route links are locatedthroughout the study area and are further described and discussed in Section 6.0.
2.7 Evaluation of the Alternative Routes
Possible alternative route combinations were recalculated after making the route link
adjustments noted above, and were evaluated in detail. The analysis of the alternatives
presented in Section 7.0 involved the inventory and tabulation of data related to multiple
environmental and land use evaluation factors. Many of these factors relate to natural
and man-made features that would be crossed by an alternative route (e.g., number of
stream crossings, and length across cropland). Some of the evaluation factors include
features that are counted or measured if an alternative route link would be within a
specified distance of a feature (e.g., airports or communication towers). Another factor
included the length of an alternative route that runs parallel to and/or utilizes existing
compatible corridors such as power transmission lines and public roads. The number or
amount of each factor was determined primarily by reviewing recent aerial photography
within a Geographic Information System (GIS) mapping program, and, where possible,
verified by visual observations during field reconnaissance.
Page 2-14 Halff Associates
65
n 0nRn0 °n
3.0 ENVIRONMENTAL SETTING OF THE STUDY AREA
3.1 Constraints Mapping
Halff identified environmental and land use constraints within the study area. A
constraints map was developed that identifies the locations of environmentally sensitive
areas, exclusion areas, avoidance areas, and other land use constraints, all of which are
mapped on an aerial photograph base map that is contained in Appendix G; a reduced
copy of the constraints map is shown in Figures 3-1A and 3-1B. The information
obtained and reviewed in completing this study, and the environmental and land use
constraints depicted in these figures, are described in detail in the following sections.
3.2 Physiography and Geology
The study area falls within portions of Anderson, Freestone, Henderson, and Navarro
Counties in northeast Texas. As shown in Figure 3-2, the study area lies in the Interior
Coastal Plains subregion of the Gulf Coastal Plains physiographic region (or `province'),
near the boundary of the Blackland Prairies subprovince of the same province (Bureau
of Economic Geology [BEG], 1996). Bedrock features throughout the study area were
created by sedimentation and progressive construction of the southern continental
margin of North America. Outcrops in the area are rare, since the last 60 million years
has been a process of continual sinking rather than uplift (Spearing, 1991).
Rocks and unconsolidated deposits from the Tertiary and Quaternary geologic periodsare represented in the study area. The Interior Coastal Plains province is composed ofTertiary period alternating belts of resistant uncemented sands among weaker shales
that erode into long, sandy ridges. Lignite is mined extensively along a wide band in
northeast Texas. This Eocene deposit, which is compressed peat derived from plant
material, was laid down 50 million years ago in the muddy areas between river channels.
The Blackland Prairies subprovince is comprised of limestone chalks, shales, and marls
formed in the latter part of the Cretaceous period (66-144 million years ago; Spearing,1991). However, no surface Cretaceous bedrock is mapped within the study area.
Quaternary period geologic features are consolidated and unconsolidated deposits from
wind or alluvial processes occurring over the past two million years.
Halff Associates Page 3-1
66
E 0nNnW E
The topography of the study area is mainly rolling hills between the low, flat floodplains
of the Trinity River. The Interior Coastal Plains subprovince generally ranges in
elevation from approximately 300 to 800 feet above mean sea level (msl) (BEG, 1996).
The elevation of the study area ranges from approximately 220 feet above msl in the
southern part of the study area along the Trinity River to elevations near 500 feet above
msl in somewhat gently rolling terrain along the eastern edge of the study area in
Henderson County (NGS, 2009).
Outcropping geologic formations across the study area get progressively younger from
west to east, with strata that dip east and gradually to the southeast. One miniscule part
of the study area dates from the Paleocene and includes the Simsboro Formation
(material). Most of the study area is underlain by formations that date from the Eocene
and include (from west to east) the following formations: Calvert Bluff Formation
(mudstone, sandstone, and lignite); Wilcox Group undivided (quartz sand, glauconite,
silt, clay, and lignite); Carrizo Sand (quartz sand, feldspar, and chert grains); Reklaw
Formation (clay, silt, glauconite, quartz sand, ironstone); Queen City Sand (quartz sand,
clay, ironstone); Weches Formation (glauconite, glauconitic marl, quartz sand, and clay);
and Sparta Sand (quartz sand and clay).
Quaternary formations within the study area primarily include alluvium, floodplain, and
channel deposits associated with the Trinity River and major streams such as Catfish
Creek, Walnut Creek, and Tehuacana Creek. The fluvial deposits associated with these
streams are composed of clay, silt, and sand. Fluviatile terrace deposits composed of
gravel, sand, and silt are also present (USGS and BEG, 1992; BEG, 1996).
Page 3-2 Halff Associates
67
__.. ...
A
.
.. _ .. _ . ......................... .. ___.
H
J. ^.
_ . • c
.
_. ^. , . ^.
f K
^
:^ , . ti u ^T. ,
\-^-
1
7w
F u3a .
- + GiA
w
t
^^^ ^^. 4 / ^ ^^ - _qy . .'•`^ ^us^ .:: ^. .
F v^ 'g
;Y^.. . .. ,.
., r... ,^ . .. ,. , , d . , , .. . < .
.-_. T, ^ ^ ' ^ . . .
......^.
. ^.»`:^ .
MN
d
^
C
^
C_
O
A
LL
O
O_
U^
N
^
Uu^
OZ
TJJ
Z0F -zWHZ
YZ
mF-LLWJ
WCD
2F-
_ ... ............._..... ...........__ ...,........._..............._.
$ ^ .-,• ^
.
. ., ^ .}^;.;. _ ..... ..
` s r
. _.._ ^. .__.. -,. .«,..._.... _ ..___,_,^,.,..^.
^? . . ^ . .. .ad':a .
mr^'9
ICl
cnma
^^^a^
Q)
doEm
.0CDxvc^an
c_
^^rnU-
-0NN
GlNf04)a
L<caa
d
Om
cbv5rn
LL
OcO
UJ
N
A
tH
lUHOZ
TJJ
Z0HZWHZ
YZ
J
HLLlUJ
W
0-(nxF-
n tONEn n
^
SC
I S X
Guadalupe
R:nk
Central High Plains
eseg ;^'- PHYSIOGRAPHIC MAP OF TEXAS1996
aALaAnIreC 13i.TR1;:'1I) OF I.f't:,}.^tlh9lt [.aLl?I:(-.)C,i1'THE l tN[VftSi I'i' OF Tt ar4fi AT sttt,.i"T1N
t"n;sor`ztr Starimi. Box X^^ Azrsz'rn 1 xav 7877?•Ji+X14^....J,
(512) 171-15,34
Ldn(65 l i
} Southern
HighII Plains
J^... .^iaapCANo
0 80 100 150 200 mites
0 100 200 300 Idtameters
Study Area
•
"
^^.. r;K$T^SM {V
r`> ^ 5- ^^•^l{ i..^^r'\ ^ ^J^^^_. w.y. _
{ . ^ ^^^^} ^ },'ht` 1-.. ♦
. ..
`-
, y. ^^.O
'
^
..,.r 'f 4 ^^,^ ^Y•,`^ '^ S, ^
r^wau^`^S'i^ ^1'Y
^t .r it
ll
n v, c r- ^' ^I€ TCIP(DGRAPHY : G£GFAG RT#st,tCl't/Pl"- BF'Cf3.'3C "YPE$t'Ulfcoastal Rams
C6astal Prairies 30D {} Nearta Elat praide, <1 #im[ to Gulf Nearly flat strata DsNaio sands and muds1r"tltlk`CffAsm ptai}1. 800. ._ ....,. •^_.^. Parallel ridges (questas) and valleys^ .. . .. ^.... i Beds tilled t[rrrard Gun `unconsolidated sands and muds
1000 450 g:Low roUln terrafn...-... __
: t3e^is i 11ed south and east ^ ... ^ .. ._chatks and rtsarfs
1 e^50.^..,_____^„_ , 45p, ..^..,_., . ; Low stairsfap Nis caest;, plains east.........^..,^____......_.,__________^.m.^...^.., Strata dip east, • „_,,.^...,.._ w,„-t•.,_Gatcareous east; sandy rest_ ,_,^.......,,,_,.......,,
3002,3 00-
454 Flat upper surface rrtAR tacz+ canyons1 aD0 SteeG>^lted canyons
= Beds dip south nurrrrat Fault eW 1' t:imostavzes and dobrnAes
:t irn0slaics and dobnades
.:. 4200 ?2000
1700^
Mew-formed terrain: highs to va!astKnoGt y pI^ ui, rounded by questas
Untautled, near-h+arqtontal [>tsfsCent ritre€at dips. ^stiongty taulted
Carbonates atut a:i3uviat sedimentsGta ndes metars or bics d t^A19tfAI;P•^ ;
t3 h Piains^3000 900 p Low npflh-south t' e€ (qu ES#rs} i t dip; rTm1V7 tattle
p so lat^nLtrY BStdrtasi 33nd5t@n€rsS shales
.- __. _ . - __._,Centra €
.^.^..4350
_^.. ^,m..29(.k?
.....^.._...._. ...._.^...^..... ^...Flat prauios skope saasf and scurFh ' S
:....A^h!._.
dips^......_.^
east and south Eollan sitls and tine sandsCanadian Breaks 3800 , 2350 Hqhy dzssected: bcal satut^nn uattaysSouthern 380Q . ?200 Plat axrany Playas. local dune fields. _. ....,..._
B?5Q 17pp._...,.,,^,..^,^, ..w.._....,^. . . ............._.......,,^ _...^..,...,,,^...
Norlh south rrwuninins and bas^ns s Sotrro com tox 1atAin and tau@i^ .,.,..,.^._.__... _..^ . ,^t neauas; metarnar bics: sediments
FIGURE 3-2. PHYSIOGRAPHIC REGIONS OF TEXASNEW BETHEL
345 kV TRANSMISSION LINE PROJECTOEM
Source: Bureau of Economic Geology, 1996 ®®n HALFF
Halff Associates Page 3-7
72
! nnNnn n
THIS PAGE LEFT BLANK INTENTIONALLY
Ol,. G J-U Halff Associates
73
0 /nEM0 1
3.3 Soils
3.3.1 Soil Associations
Data from the NRCS (formerly the Soil Conservation Service) were used to identify and
characterize the soils that encompass the study area. In 2006, the NRCS completed its
Digital General Soil Map of the United States, which consists of a broad inventory and
mapping of general soil association units. Soil associations are main patterns of soils
defined and delineated based on criteria such as soil texture, parent material, slope,
characteristics of horizons in soil profile, and degree of erosion (NRCS, 2006). The
NRCS project merged soil association data from the myriad of county soil surveys into a
seamless national data set. This soil mapping approach resolved a basic challenge in
using county soil surveys, which often reflect different soil names for similar soils from
one county to the next. A brief description of each soil association's general
characteristics is in Table 3-1, and Figure 3-3 shows the NRCS-mapped soil
associations within the study area. The soil associations in the seamless NRCS map
were compared graphically with the soil associations defined and mapped in the county-
level soil surveys for Anderson, Freestone, Henderson, and Navarro Counties (SCS,
1974 - 2002), and the column on the right side of Table 3-1 shows the names of the
corresponding soil association(s) from each county soil survey.
riairr AssociatesPage 3-9
74
n n^^n
Table 3-1. Soil Associations within the Study Area.Soil Association ^
Unit # - NameMaStudoy
Area l Description of Soil Association 2 County Soil Survey:3p o Soil Association Name
UPLAND SOILS (77,4% of Study Area)
Loamy, moderately slowly permeable, gently7202 - Pits-Bigbrown 2.4 sloping, well drained soils on uplands and high Freestone- Bigbrown
stream terracesLoamy, very slowly permeable, nearly level to
7306 - Tabor-11 1 strongly sloping, well drained and moderately
Gredge-Edge well drained soils on uplands and high stream Freestone Edge Taborterraces
7331 - Freestone- Loamy to sandy, nearly level to moderately Anderson. Axtell-Lufkin-Derly-Bienville- 8.4 steep, well drained soils on uplands Stidham; Darco; Fuquay-Attoyac-Annona Kirvin-Darco
Freestone: Cuthbert7354 - Gredge- Fine sandy loam, very slowly permeable toCrockett 2 0 moderately permeable, gently sloping to sloping Navarro: Axtell-Konawa
soils.Loamy to sandy, very slowly permeable and Anderson Axtell-Lufkin-
7355 - Rader-Lufkin-16 4 slowly permeable, nearly level to moderately Stidham; Darco
Gredge-Crockett .steep, moderately well drained to well drained Henderson: Axtell-soils on rid eto s and side slopes. FreestoneLoamy, moderately permeable and very slowly
7409 - Konsil-Gasil-2 2 permeable, nearly level to strongly sloping, well Freestone: Silawa-Gasil-
Axtell .drained and moderately well drained soils on Taborstream terraces and uplands
7508 Wolfpen- Loamy and sandy, moderately permeable and Freestone: Wolfpen-Oakwood 0.5 moderately slowly permeable, gently sloping to Cuthbert-Pickton;
steep, well drained soils on uplands Oakwood-KirvinSandy, moderately permeable, gently sloping to
7525 - Silstid-Padina 0.8 moderately sloping, well drained soils on Freestone: Padina-SilstiduplandsSandy to loamy, moderately permeable and Freestone: Pickton-
7549 - Tonkawa-40 rapidly permeable, nearly level to moderately Tonkawa
Tenaha-Pickton steep, well drained and excessively drained Anderson- Darco;soils on upland s Fu ua -Kirvin-Darco
7550 - Wolfpen- Loamy and sandy, moderately permeable andPickton-Cuthbert 88 moderately slowly permeable, entl slo tog y ping Freestone: Wolfpen-
steep well drained soils on up lands Cuthbert-Pickton7662 - Sacul-Kirvin-
2 0 Loamy, moderately slowly permeable, stronglyCuthbert .
sloping to steep, well drained soils on uplands Freestone: Cuthbert
Clayey and loamy, very slowly permeable, Freestone: Kaufman-7732 - Wilson-
1 4 nearly level to gently sloping, moderately well Trinity; Burleson-WilsonCrockett-Burleson .
drained soils, on ancient stream terraces. Navarro- Trinity-Kaufman;Axtell-Konawa
7741 - Woodtell- Sandy, moderately permeable, gently sloping to Anderson: DarcoWolfpen-Pickton 78 moderately steep, well drained, soils on Henderson, Pickton-
ndgetops and upland side slopes Wolfpen
7742 - Woodtell- Loamy, very slowly permeable and slowlyFreestone <0.1 permeable, moderately well drained, gently Henderson Woodtell-
s Floping to moderately steep soils. reestone
7752 - Wilson- Clay loam and fine sandy loam, slowlyCrockett 1 3 permeable, nearly level to sloping soils on Navarro: Crockett-Wilson
u lands.
raye 3- i u Halff Associates
75
N nnwnn n
Table 3-1. Soil Associations within the Study Area.Soil Association ^^
Ma p Unit # - Name^ StudyArea !o Description of Soil Association 2 County Soil Survey:
Soil Association Name 3BOTTOMLAND SOILS (22.6% of Study Area)
Loamy, moderately to moderately rapidly7364 - Nahatche-
0 5permeable, nearly level, somewhat poorly Freestone- Nahatche-
Hatliff ' drained to moderately well drained soils on flood Hatliffplains of creeks
Anderson: Kaufman-Trinity
7392 - Tinn- Freestone Kaufman-Kaufman- 21.8 Deep, clayey, nearly level soils on bottom lands. TrinityGladewater Henderson: Trinity-
KaufmanNavarro- Trinity-Kaufman
7697 - Trinity- Clayey, very slowly permeable, somewhat Henderson: Trinity-Kaufman 6.7 poorly drained, nearly level to gently sloping Kaufman
soils in flood lams and bottom land. Navarro Trinity-KaufmanSources. Digital General Soil Map of the United States (NRCS, 2006); and NRCS (formerly SoilConservation Service, or SCS) soil surveys for the following counties: Anderson (SCS, 1975), Freestone(2002), Henderson (1979), and Navarro (1974)Notes:1. Map unit # and name correspond with the number and name assigned to each soil association in th e
2006 NRCS Digital General Soil Map of the U.S., as shown for the study area in Figure 3-4.2. The description used for the soil association is a composite of the descriptions for the soil associations
from county soil surveys that correspond geographically with the 2006 NRCS Digital General Soil Map.3. This column shows the soil association names from the county soil surveys that correspond to the
2006 NRCS Digital General Soil Map.
Halff Associates Page 3-11
76
n nnonm e0
THIS PAGE LEFT BLANK INTENTIONALLY
Page 3-12 Halff Associates
77
}JJ
Z0
HZWF-Z
Z
m
F-WW
WC^
x
N 0nwsM n
There are 18 different soil associations within the study area, of which 15 are upland
soils and three are bottomland soils. The bedrocks discussed in the previous section
are the foundation for the soils found within the study area, and soil maps bear a general
similarity with geologic maps of the area (compare Figures 3-2 and 3-4). Regardless of
the type of underlying bedrock, the upland soils throughout the study area occur
generally on flat to strongly sloping topography and have predominantly sandy and
loamy texture. Soils formed in bottomlands are typically clay, occur on slopes of variable
steepness, and comprise 29.0 percent of the study area (SCS, 1974 - 2002).
3.3.2 Prime Farmland
The United States Congress, in the Farmland Protection Policy Act (FPPA), definesprime farmland as " land that has the best combination of physical and chemical
characteristics for producing food, feed fiber, forage, oilseed, and other agricultural crops
with minimum inputs of fuel, fertilizer, pesticides, and labor, ..." (7 U.S. Code Section
4201(c)(1)(A)). Such lands have the soil quality, growing season, and moisture supply
needed to economically produce sustained high yields of crops when treated and
managed, including water management, according to acceptable farming methods.
Additional potential prime farmlands are areas with soils that meet most of the
requirements of prime farmland but fail because they lack water management facilities
such as irrigation systems, or they lack sufficient natural moisture; such areas would be
regarded as prime farmland if these areas were irrigated.
Just over one-tenth of the study area is comprised of soils that are considered prime
farmland according to county soil surveys (SCS, 1974 - 2002); the majority of these
soils are located in close proximity to the Trinity River floodplain. However, the NRCS
responded to Halffs solicitation for information in a letter dated June 24, 2013 (see
Appendix A), stating, "The proposed project is exempt because transmission lines are
not a conversion of Important Farmlands and the site can still be used after
construction." The NRCS encourages the use of accepted erosion control methods
during the construction of all projects, regardless of exemption status.
Halff Associates Page 3-15
80
0 nnNnn 03.4 Water Resources
3.4.1 Surface Water and Floodplains
The study area lies within the Trinity River watershed, with approximately 66 percent of
the study area within the Lower Trinity-Tehuacana basin, and 24 percent within the
Upper Trinity River basin (located in the northwestern portion of the study area) (TCEQ,
1999; TWDB, 2009a). The remainder of the study area falls within the Cedar Creek
basin (5 percent) and the Richland Creek basin (5 percent).
The Trinity River is the predominant river within the study area, and is a perennial
stream that flows southeastward across the western portion of the study area (NGS,
2013). Major perennial Trinity River tributaries within the western portion of the study
area include (from west to east) the following: Cedar Creek and its primary tributary
Walnut Creek; Turkey Creek including its tributary Tick Branch; Wildcat Creek including
its tributaries Prairie Creek and Barron Creek; Mitchell Branch; Saline Branch and its
tributaries Hall Branch and Bee Branch. The eastern edge of the study area is drained
by Catfish Creek, which is a perennial tributary to the Trinity River. Major perennialtributaries to Catfish Creek are located east of the study area. Other major perennial
Trinity River tributaries within the southern portion of the study area include (from west to
east) the following: Tehuacana Creek and its tributaries Cottonwood Creek, Pin Oak
Creek, Prairie Creek and Big Brown Creek; Rocky Branch; Edwards Creek including its
tributaries Cold Springs Branch and Willow Creek; Indian Creek. Many named and
unnamed intermittent and ephemeral streams are present throughout the study area,
many of which support riparian vegetation that was observed in the aerial photography
and field reconnaissance.
Two surface water bodies that exceed 500 acres are wholly located within the study
area. The largest of these is Fairfield Lake (2,159 acres) which is located approximately
5 miles northeast of the City of Fairfield in the southern portion of the study area.
Trinidad Lake (710 acres) is in the northwest portion of the study area approximately 1.5
miles south of the City of Trinidad. A small portion (4,389 acres) of the much larger
Richland Chambers Reservoir extends into the western part of the study area where
Richland Creek continues downstream of the reservoir's dam. Other moderately sized
(90 to 155 acres) water bodies, most of which are located on-channel to larger drainages
Page 3-16Halff Associates
81
n MnNn0 n
in the study area. Additionally, there are dozens of smaller stock ponds, flood control
reservoirs, small private recreational lakes, and soil conservation lakes throughout the
study area ranging in size from less than 1 acre to 56 acres.
State legislation in 1997 (see Texas Water Code Section 16.051) modified the state-
wide water resources planning process by authorizing regional planning groups to
recommend ecologically unique river and stream segments to the Texas State
Legislature in regional and state water plans (TWDB, 2009b). A primary purpose for this
approach is to ensure that future water impoundments do not destroy stream segments
that are considered unique under specified designation criteria (see 31 Texas
Administrative Code Section 357.8), which include biologic functions and habitat for
threatened and endangered species. State designation as ecologically unique would
also prevent state agencies or municipalities from acquiring property or easements that
would destroy the ecological values forming the basis for the designation. Part of the
process for designating ecologically unique stream segments requires regional water
planning groups to coordinate with TPWD about candidate stream segments (TWDB,
2009b and 2009c). Within the study area, TPWD has identified the following river or
stream segments as ecologically significant under the relevant designation criteria: the
Trinity River in Navarro, Henderson, Anderson, and Freestone Counties; and Catfish
Creek in Anderson County (TPWD, 2002a; 2002b). The regional water planning groups
(Region C and Region I) with responsibility for the study area considered TPWD's
recommended stream segments for inclusion in the 2012 State Water Plan, but did not
forward any proposals to TWDB for designating these or any other stream segments as
ecologically unique (TWDB, 2012). Consequently, TWDB did not include any of the river
or stream segments noted above in its list of recommendations that is part of the 2012
State Water Plan (TWDB, 2012), and the Texas Legislature has therefore not yet
considered the matter.
Planning meetings between TPWD and TWDB have clarified that the only legal effect of
legislative designation of a unique stream segment would be to prevent the development
of a reservoir on the designated segment (TWDB, 2011 b), and would not preclude thecrossing of such features by a power transmission line. The most recent draft regional
water planning group report addressing these stream segments does not include a
recommendation for designating of either as ecologically significant, but calls for the
haitt AssociatesPage 3-17
82
E -En^n
creation of a working group to further clarify the legal effects of making a legislative
designation (TWDB, 2011b; TWDB, 2011c). Nevertheless, TPWD's recommendations
relating to these water features remain a planning consideration, and correspondence
from TPWD recommended that these stream segments not be spanned by a
transmission line, where feasible (TPWD, 2013a).
Research into the water quality for monitored water bodies within the Trinity River
watershed portion of the study area indicates water quality concerns related to effluents
from a number of large municipal wastewater treatment plants in the Dallas/Fort Worth
Area, as well as stormwater runoff from urbanized and agricultural areas. Two streams
within the study area are included in the 303d list of impaired water bodies maintained
by the Texas Commission on Environmental Quality (TCEQ, 2012). These streams
include the Trinity River (for the entire length of the study area) and Catfish Creek (from
US 287 to just upstream of SH 19 east of the study area). Listing criteria for the Trinity
River include polychlorinated biphenyls in edible tissue and dioxin in edible tissue.
Listing Criteria for Catfish Creek includes bacteria and depressed dissolved oxygen. No
other water quality concerns were identified within the portion of the study area located
in the Trinity River watershed.
FEMA data for counties within the study area varies from detailed floodplain analyses in
Navarro County, redelineated floodplains using historic data in Anderson and Henderson
Counties, and Flood Insurance Rate Maps for Freestone County. Floodplains have
been mapped for all major streams. Digital versions of available FEMA maps (FEMA,
2013) were included in the inventory of study area features.
3.4.2 Groundwater/Aquifer
The Carrizo Aquifer is the only major aquifer in the study area and it extends throughout
(TWDB, 2011 a). This aquifer is part of the Carrizo-Wilcox aquifer system, extending in a
wide arc from the Louisiana border to the border of Mexico, adjacent to and northwest of
the Gulf Coast Aquifer. This aquifer consists of the Wilcox Group and the overlying
Carrizo Formation of the Claiborne Group. The Carrizo-Wilcox Aquifer is primarily
composed of sand locally interbedded with gravel, silt, clay, and lignite (TWDB, 2011 a).
Within the vicinity of the study area, the aquifer occurs in the Carrizo Sand Formation.
Groundwater recharge within this aquifer zone is diffuse and occurs primarily from
Page 3-18 Halff Associates
83
E an^n^ n
precipitation across interstream areas. Overlying soil type significantly affects recharge
rates for the Carrizo-Wilcox Aquifer (BEG, 2013b). The Carrizo-Wilcox Aquifer reaches
approximately 3,000 feet in thickness. However, freshwater saturation averages 670
feet (TWDB, 2011 a). Municipal use and irrigation account for approximately 35 percent
and 51 percent of water use from the aquifer respectively (BEG, 2013b). The
groundwater resources within the study area are within three different groundwater
conservation districts (GCD) including the Mid-East Texas GCD, the Neches and Trinity
River Valleys GCD, and the Anderson County Underground Water Conservation District
(TWDB, 2013a, 2013b, and 2013c). In general, water from this aquifer within the
outcrop area is fresh but hard (i.e., typically less than 500 mg/L total dissolved solids),
and salinity of the water varies from slightly to moderately saline (TWDB, 2011 a).
3.5 Ecology
3.5.1 Vegetation
The NRCS has studied the characteristics of ecological regions for decades to better
understand the biology and management of natural resources. The NRCS published a
handbook in 2006 that maps general Land Resource Regions (LRRs) that share similar
geology and land physiography, moisture and climate, and soils characteristics (NRCS,
2006a). The study area is within two LRRs. The majority of the study area falls within
the Southwestern Prairies Cotton and Forage Region (which is part of the southern
Great Plains), which has annual precipitation averaging from 26 to 46 inches. The
southeastern portion of the study area within Freestone County falls within the South
Atlantic and Gulf Slope Cash Crops, Forest, and Livestock Region, which has annual
precipitation averaging from 44 to 63 inches (NRCS, 2006a).
As shown in Figure 3-4, NRCS soil scientists have further subdivided the LRR within the
study area into four Major Land Resource Areas (MLRAs). As the criteria used to define
both MLRAs and the larger LRRs focus fundamentally on soils and soil-forming factors,
the delineation of MLRAs is therefore closely linked to the various soil associations that
have been mapped over the past half century. This approach to the study of vegetation
focuses on the land's potential for supporting natural vegetation or agricultural practices,
rather than simply reporting a snapshot of vegetation as it may exist at a single point in
Haltt Associates Page 3-19
84
0 nnEnM M
time. A summary of key attributes associated with the four MLRAs in the study area is
shown in Table 3-2.
Although various factors distinguish the ecology of the MLRAs in the study area, there
are also ecological characteristics that are essentially common for all the MLRAs
represented in the study area. For example, annual precipitation comes principally as
rainfall from convective thunderstorms in the spring and fall, and the growing season
generally ranges from 225 to 290 days (NRCS, 2006a). Topography throughout the
study area is generally characterized as nearly level to gently sloping plain, with
occasionally steeper slopes where streams have cut into the landscape.
Nage 3-Zo Halff Associates
85
}JJ
ZOHZwFZ
YZ
J
HU -wJW0QIL
F-
N anUR0 n
Table 3-2. Major Land Resource Areas (MLRAs) within the Study Area.11
MLRA Name and(NRCS Number) *
StudyArea
IGeology
AverageAnnual
11 11General Native
% Preci Vegetation
Land Resource Region : Southwestern Prairies Cotton and Forage Region
Texas Blackland Prairie Cretaceous chalk, mixed tall and mid prairie,
Northern Part (86A)8 claystone, marl, and 30 - 46 in. grasses, with savanna
forests primarily inshalelowlandsoak savanna vegetation,
Tertiary fluviodeltaic and some mixed pine-Texas Claypan Area,Southern Part (87A)
70 marine sediments:sandstone, siltstone, 27 - 45 in. hardwoods in the
southwestern part of theshale, sands, silts, clays area, hardwood forests on
bottomlandTexas Claypan Area, <1 Tertiary marine sands,
39 - 45 in oak savanna vegetation,Northern Part (87B) silts, clays .
native pines in some areasLand Resource Region: South Atlantic and Gulf Coast Cash Cro s, Forest, and Livestock Region
Tertiary and Cretaceous
Western Coastal Plain marine sediments:
(133B) 21 sandstone, siltstone, and 39 - 63 in. pine-hardwood vegetationshale, calcareous claysand marls
Source: NRCS, 2006a."' The MLRAs occurring within the study area are listed from west to east; the NRCS-assigned numericalcode for each MLRA is noted in parentheses.
Prior to modern human settlement, native vegetation communities were characterized by
a high level of species diversity, and varying mixes of herbaceous (primarily grass) and
woodland species. Within the native prairie ecosystems (i.e., Texas Blackland Prairie),
occasional prairie fires ensured grass dominance over ever-encroaching woodland
trees. Prairie and savannah grasses that in prehistory dominated areas less favorable
for plant growth (e.g., relatively shallow soils) included short and mid grasses such as
buffalograss (Bouteloua dactyloides), silver bluestem (Bothriochloa laguroides), andsideoats grama (Bouteloua curtipendula). Dominant grasses on favorable sites
throughout the study area were primarily tall grasses, which included little bluestem
(Schizachyrium scoparium), big bluestem (Andropogon gerardii), Indiangrass(Sorghastrum nutans), and switchgrass (Panicum virgatum). Upland savanna
woodlands in the western part of the study area (i.e., Northern and Southern Post Oak
Savanna) were predominantly post oak (Quercus stellata) and blackjack oak (Quercusmarilandica) savanna forests. Over a centurv of farminn rnnrhinn nnri jerhnn
development has resulted in widespread replacement of native prairie grass species with
introduced pasture grasses such as Bermuda grass (Cynodon dactylon), King Ranchbluestem (Bothriochloa ischaemum), Johnson grass (Sorghum halepense), weeping
i-ialtt Associates Page 3-23
88
N nMENN n
lovegrass (Eragrostis curvula), and kleingrass (Panicum coloratum). However, remnant
patches of native prairie grasses (predominantly little bluestem) may still be found within
the study area. Woodland trees within the study area generally reflect the same mix of
trees thought to exist in prehistory, with the exception of new tree species that were
introduced by settlers. Upland wooded areas in the eastern part of the study area
(Western Coastal Plain) typically consist of loblolly pine (Pinus taeda), shortleaf pine(Pinus echinata), sweetgum (Liquidambar styraciflua), southern red oak (Quercusfalcata), white oak (Quercus alba), flowering dogwood (Cornus florida), and post oak.
This general description of the overall vegetation type based on NRCS research is
consistent with other regional delineations and descriptions of ecological regions in north
central Texas. Research completed in 2007 for TCEQ produced delineations of four
ecoregions in the study area that correlated closely with the NRCS MLRAs. The TCEQ
delineations (from west to east) include the following: Southern Post Oak Savanna
(eastern part of Navarro county and most of Freestone County), Floodplains and Low
Terraces (along Trinity River), Northern Post Oak Savanna (western part of Henderson
County and Anderson County), and Tertiary Uplands eastern part of Henderson County
and Anderson County) (Griffith et al., 2007). The main difference between the NRCS
MLRA and the TCEQ ecoregions is that no Blackland Prairie is mapped within the study
area in the TCEQ ecoregions. Maps and information from other sources have
maintained a more generalized approach to defining ecological regions, which is quite
similar to the NRCS designations at the LRR level. For example, the Gould's ecoregion
map defines only two major ecoregions in the study area, which are Blackland Prairie
(Navarro County, western Henderson, western Freestone, and northwestern Anderson
counties) and Post Oak Savannah (eastern Henderson, eastern Anderson, and eastern
Freestone counties) (TPWD, 2007). Other discussions of regional ecology provide
similar treatment of major ecoregions (Hatch et al., 1990; Diggs et al., 1999).
3.5.1.1 Terrestrial Vegetation
GIS data from the TPWD Texas Ecological Mapping System were used to estimate
areas of major types of existing vegetation cover within the study area. These data were
developed from satellite imagery with 10-meter by 10-meter mapping resolution
collected from 2005 to 2007 and refined with in situ data. Using this refined imagery,
TPWD created a statewide land cover data set that includes a sufficient number of land
rage 3-14 Halff Associates
89
0 0nngN 1
cover classes to provide insights for planning and management at a variety of scales(TPWD, 2012). For the purpose of this study, the more specific ecological classificationswere grouped into nine general land cover classes. Figure 3-5 displays the TPWD landcover data by different land/vegetation cover types, as it was grouped for the purpose ofthis study.
Halff AssociatesPage 3-25
90
0 0nEn0 n
THIS PAGE LEFT BLANK INTENTIONALLY
Page 3-26Halff Associates
91
rJJ
ZQ_
HZW
z
Z
Jco
F -LLWJ
W0
IL
U)xF-
M nnNE0 n
Use of these digital data yielded the following estimates of cover as applied to the study
area: 33.2 percent upland forest, 36.0 percent grass-dominated rangeland and
pastureland, 22.9 percent bottomland forest, 3.6 percent open water, and 2.8 percent
cultivated cropland. The remaining cover classes. each accounted for less than 1
percent of total acreage within the study area. This review of land cover in the study
area clearly shows that woody vegetation is the predominant vegetation type. Areas
dominated by herbaceous vegetation (grass-dominated rangeland and pastureland and
cultivated cropland) are generally used for some level of agricultural production ranging
from intensively managed croplands (including grain crops and hay meadows) to
variably managed rangeland pastures (i.e., the presence and extent of invading woody
species varies widely).
The description of study area terrestrial vegetation that follows is based on field
observations, interpretation of recent aerial photography (USDA, 2014), and a review of
reports and maps produced by NRCS (2006b), TPWD (1984 and 2007), and TCEQ
(Griffith et al., 2007).
The vegetation within the Texas Claypan Area (Post Oak Savannah) is a mosaic of mid
and tall grass prairies and upland woodlands dominated principally by post oak and
blackjack oak trees, along with a variety of other deciduous tree species. Although
much of the area within this MLRA has been cleared of original prairie and woodland
vegetation to create croplands, this portion of the study area continues to have the
highest concentration of remnant upland oak and mixed woodlands. Tree canopies
within post oak woodlands grow to a height of 40 feet or greater and woodland
understory vegetation is frequently densely covered with shrubs, vines, and grasses.
These same oak and prairie grass savanna ecosystems extend into the adjacent
Blackland Prairie MLRA, with the principal difference being that upland woodland areas
diminish significantly in favor of herbaceous species, except for forested bottomlands
and fencerows. A list of plant species commonly found in upland areas throughout the
MLRAs in the study area is presented in Table 3-3. The prairie component in these
MLRAs was originally maintained by periodic fires that destroyed invading woody
species such as eastern red cedar. During historic times, farmers -and ranchers have
used fire as well as mechanical clearing and herbicides to suppress encroaching woody
HaIif Associates Page 3-29
94
M 0nNnM n
plants. In the eastern part of the study area, the Western Coastal Plain is dominated by
mixed pine and hardwood trees.
Table 3-3. Upland Plant Species in the Study Area.Common Name Scientific Name Common Name Scientific Name
Grasses Ma 'or Associated Wood Plants (continued )Bahia grass Pas alum notatum Hone locust Gleditsia triacanthosBeaked panicum Panicum anceps Loblollpine Pinus taedaBermuda grass C nodon dact lon Plum Prunus sBig bluestem Andro 0 on gerardii Poison ivy Toxicodendron radicansBristle grass Setaria spp Post oak Quercus stellataCurly threeawn Aristida desmantha Shumard red oak Quercus shumardiiCylinder jointtail grass Coelorachis c lindrica Shortleaf pine Pinus echinataDropseed Sporobolus s. Southern red oak Quercus falcataEastern gamagrass Tripsacum dactyloides Sweet um Li uidambar st racifluaFlorida as alum Pas alum floridanum Sumac Rhus sHairy rama Bouteloua hirsuta Virg inia creeper
.Parthenocissus uin uefolia
Indian grass Sor hastrum nutans Wax myrtle Morella ceriferaIndian woodoats Chasmanthium /atifolium White oak Quercus a/baJapanese brome Bromus "a onicus Winged elm Ulmus alataJohnson grass Sorghum hale ense Yaupon Hex vomitoriaKing Ranch bluestem Bothriochloa ischaemumKlein grass Panicum co/oratumLittle barley Hordeum pusillum Representative Associated ForbsLittle bluestem Schizachyrium scoparium Alabama su le•ack Berchemia scandensPinehill bluestem Schizachyrium scoparium Asters Symphyotrichum spp.
var. diver ensPlains love grass Era rostis intermedia Catclaw sensitive-briar Mimosa nuttalliiPur leto Tridens flavus Coastal indigo Indigo fera miniataRescue grass Bromus catharticus Coneflower Rudbeckia sSand love grass Era rostis trichodes Croton
.Croton s
Sideoats grama Bouteloua curtipendula Dewber.
RubussippSilver bluestem Bothriochloa laguroides Dotted gayfeather Liatris punctataSpike tridens Tridens strictus Engelmann daisy En e/mannia pensteniaSwitch grass Panicum wr atum Evening rimrose Oenothera sTall dropseed Sporobolus clandestinus Giant ragweed
.Ambrosia trifida
Texas winter grass Nassella leucotricha llinois bundleflower Desmanthus illinoensisTexas cupgrass Erioch/oa sericea ndian blanket Gaillardia ulchellaThreeawn Aristida s. ronweed Vernonia sppTumble windmill grass Chloris verticdlata Maximillian sunflower Helianthus maximilianiWeeping love grass Era rostis curvula Prairie bluet Hedyotis nigricans
Major Associated Wood y Plants Prairie clover Da/ea spp.American beau ber Callicarpa americana Prairie vervain Glandu/aria bipinnatifidaBlack hickory Carya texana Sedge Carex sppBlackjack oak Quercus marilandica Sdverleaf nightshade Solanum e/aea nifoliumBluejack oak Quercus mcana Snoutbean Rh nchosia sCedar elm Ulmus crassifolia snow on the prairie Euphorbia bicolorCommon persimmon Diospyros vir iniana Sum weed Iva annuaCoralberry S m horicar os orbiculatus Ticktrefod Desmodium sEastern red cedar Junipqerus vir iniana Tratlin ratang
.Krameria /anceolataFarkleber Vaccinium arboreum Western ragweed Ambrosia silostach aGrape vine Vitis s. Whitemouth da flower Commelina erecta
Greenbrier Smilax P . Yankeeweed Eupatorium com ositifoliumHackberry Celtis laevi ata Yellow uff Ne tunia luteaHawthorn Crate us s. Yellow sweetclover Melilotus a/baSources. Diggs et al , 2006; Griffith et al., 2007; NRCS 2006a TPWD 1984 and 2007 d F. Idian e observations in September 2013.
rage s-:su Halff Associates
95
^ NMIN*0 n
Riparian forests represent an ecologically important component of the study area, and
occur in the floodplains of rivers and major streams such as the Trinity River, Tehuacana
Creek, Cedar Creek, Turkey Creek, and Catfish Creek. Along the major streams,
sufficient soil moisture to support these bottomland forest ecosystems is limited to
narrow bands immediately adjacent to perennial streams. Along the Trinity River, the
floodplain is much wider, reaching over 5 miles across in some areas. The relatively tall
overstory canopy of riparian forests is a mix of many tree species, which may include
American elm (Ulmus americana), pecan (Carya illinoiensis), black hickory (Caryatexana), black willow (Salix nigra), green ash (Fraxinus pennsylvanica), water oak(Quercus nigra), sweetgum (Liquidambar styraciflua), flowering dogwood (Cornusflorida), eastern cottonwood (Populus deltoides), sycamore (Platanus occidentalis),slippery elm (Ulmus rubra), winged elm (Ulmus alata), box elder (Acer negundo), redbud(Cercis canadensis), and bois d'arc (Maclura pomifera). In the upper reaches of stream
channels, where water flow is intermittent or ephemeral, riparian forests become patchy
and brushy, with thickets that may include sugar hackberry (Celtis laevigata), and cedarelm (Ulmus crassifolia). Additional woody species often found in this vegetation type
include vines such as greenbrier (Smilax spp.), grape (Vitis spp.), and Carolinamoonseed (Cocculus carolinus), as well as shrubs such as sumac (Rhus spp.), yaupon(llex vomitoria), and gum bumelia (Sideroxylon lanuginosum). Although upland grass
species may be found in riparian areas, it is more likely to find grass species adapted for
shaded/moist environments such as Virginia wildrye (Elymus virginicus), woodoats(Chasmanthium latifolium), and switchgrass (Panicum virgatum). The typical riparian
understory may include members of a wide variety of species, but shading by overstory
trees generally results in a relatively sparse amount of herbaceous vegetation.
The bulk of the region is used for pasture and range; cropland within the study area is
uncommon. The cropland in the area is used primarily for corn, sorghum, or hay.
Managed pastureland typically consists of introduced pasture grasses such as Bermuda
grass and King Ranch bluestem, occasionally interspersed with little bluestem and other
native grasses. A variety of grasses, forbs (non-grass herbaceous plants), and woody
species pervade unimproved rangeland pastures and roadside areas. As previously
noted, unmanaged, grass-dominated areas (in the absence of fire) eventually become
upland woodland areas. These woodland areas continue to provide rangeland pasture
Halif Associates Page 3-31
96
M Mn^A
for livestock, although of decreasing forage quality and quantity. Without periodic
mechanical removal, herbicide treatment, or prescribed burning to control woody plants,
grass-dominated areas eventually develop into upland woodlands.
3.5.1.2 Aquatic/Hydric Vegetation
The hydric habitats in the study area are generally adjacent to streams, impoundments,
and depressions. The Trinity River, perennial streams, Richland Chambers Reservoir,
Fairfield Lake, Trinidad Lake, and numerous small to moderate sized man-made
impoundments comprise the major aquatic habitats of the study area. Impoundments
generally result in either permanent, intermittent, or ephemeral freshwater flat wetlands,
marshes, or fringe marshes. Vegetation in aquatic habitats is typically limited to the
shallow edges of the water. Plant species common to this habitat tvnP inr.hirla nichae
(Juncus spp.), sedges (Carex spp.), cattail (Typha latifolia), flatsedges (Cyperus spp.),and spikerushes (Eleocharis spp.). The wetter portions of bottomland forests could alsobe classified as hydric habitat, because these areas may undergo seasonal inundation
and/or maintain saturated soils.
The majority of the hydric areas in the study area that may also be jurisdictional
wetlands ( i.e., those wetland areas subject to USACE regulations) are located alongstreams and rivers. To identify areas that may potentially contain wetland habitats,National Wetlands Inventory (NWI) maps (on 1:24,000 scale topographic base maps)were examined. These maps highlight areas where potential jurisdictional wetland
features may be found, based on aerial photography and ground topography (USFWS,1989 - 1993). The NWI maps indicate that wetland areas that range in size and
classification are predominately located in close proximity to the major streams within
the study area. Livestock watering ponds are also frequently mapped water features on
the NWI maps, many of which would likely not be considered jurisdictional under currentUSACE regulations.
3.5.1.3 Commercially or Recreationally Important Vegetation
Within the study area, production of crops such as grain and hay is concentrated in the
Blackland Prairie MLRA (see Figure 3-4 and 3-5) (USDA, 2012; TPWD, 2012). The
production of forage for livestock is the most widespread use of agricultural land
throughout the study area, in terms of the number of acres (USDA, 2013). Forage in the
Page 3-32 Halff Associates
97
n I
form of hay, pasture, or silage is used principally as feed for cattle and horses. Hay
meadows (which may be rotated with pasture) are generally planted with introduced
grasses, most commonly Bermuda grass, in addition to King Ranch bluestem, Johnson
grass, tall fescue, and legumes such as alfalfa (Medicago sativa) (SCS, 1974 - 2002).Commercially important crops include corn, sorghum, and hay.
Habitat, rather than any particular plant species, is important for recreational hunting in
the study area. Aerial survey observations and historical aerial photography review
showed the large-scale alteration or conversion of habitats to support recreational
waterfowl hunting within the study area. At a lesser scale (e.g. food plots), similar
alterations are evident in forested communities to supplement foraging habitat for other
game species. Regardless of these man-made habitats, riparian forests and other
woodlands provide abundant essential cover for certain game species, most notable of
which is white-tailed deer. Birds and mammals that prefer open habitat make use of the
abundant croplands and rangeland throughout the study area. References provided by
the General Land Office identified two Wetland Reserve Program (WRP) conservation
easements. Administered through the U.S. Department of Agriculture, the WRP is a
voluntary program offering landowners the opportunity to protect, restore, and enhance
wetlands on their property. The Big Woods Mitigation Bank is located in the study area
adjacent to the east bank of the Trinity River in Anderson County. A special type of
reserve program, the mitigation bank consists of privately-owned land managed for its
natural resource values. In exchange for permanently protecting the land, the bank
operator is allowed to sell habitat credits to developers within a particular service area
who need to satisfy legal requirements for compensating environmental impacts of
development projects.
3.5.1.4 Endangered and Threatened Plant Species
TPWD maintains the Natural Diversity Database (NDD) to track known occurrences of
threatened, endangered, and otherwise rare plant and animal species throughout Texas.
Maps and data received from the NDD in July 2013, November 2013, and February
2015 indicated there are no recorded observations of state or federally listed plant
species within the study area (TPWD, 2013b; 2014; 2015a). TPWD and USFWS lists of
endangered and threatened species for Anderson, Freestone, Henderson, and Navarro
Counties include three listed plant species (TPWD, 2013c; TPWD, 2015; USFWS,
Half Associates Page 3-33
98
0 nnNn0 n
2015). These include the tinytim earth fruit (Geocarpon minimum) in Anderson County,
and the Navasota ladies'-tresses (Spiranthes parksh) and the large-fruited sand-verbena
(Abronia macrocarpa) in Freestone County.
While known from Arkansas, Missouri, and Louisiana, the tinytim earth fruit was
discovered in Texas in 2004 in Anderson County. This species is limited to saline barren
soil complexes just above the floodplain of the Neches River, which represents the
eastern boundary of Anderson County. As of 2009, TPWD recognized three populations
of this species. Two were known to occur on private property, within the acquisition
boundary of the then-proposed Neches River National Wildlife Refuge. The third site
also occurred mostly on private property, extending into the Caddo Lake State Park,
which is near the Texas-Louisiana border (USFWS, 2009a). It is unlikely the species
would occur within the study area.
The Navasota ladies'-tresses and the large-fruited sand-verbena are Texas endemics
generally associated with the sandier upland soils of the post oak woodlands (USFWS,
2010; TPWD, 2013d). The large-fruited sand-verbena is known only from three counties
and is restricted to sparse herbaceous vegetation in deep, somewhat excessively
drained sands in openings in post oak woodlands. All known sites are underlain by
sandy Eocene strata. Freestone County has Eocene geology and sandy soils that may
support the large-fruited sand verbena. A relatively small area located southeast of the
Big Brown SES mine is mapped as an Arenosa series soil, a fine sand somewhat
excessively drained, which could serve as suitable habitat. However, the majority of
Freestone County within the study area is primarily composed of floodplain forests of the
Trinity River and other major streams. It is unlikely that this species would be found
within the study area.
The Navasota ladies'-tresses (Spiranthes parksii) is an endemic Texas orchid. This
plant is clearly associated with the Post Oak Savannah vegetation type of east-central
Texas, and is found in openings in post oak woodlands. The Navasota ladies'-tresses is
adapted to life in the xeric, upland forest. It is rarely found in floodplain forests or
openings or open areas dominated by tall grasses (Wilson, 2013). The orchid is found
mostly along drainage areas that represent naturally disturbed areas, and is rarely if ever
found in unnaturally disturbed areas such as roadsides, utility line rights-of-way, or open
Page 3-34 Halff Associates
99
top related