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Environmental Resource Inventory

Mansfield Dam Low Water Crossing Recreation Area

Prepared for

Lower Colorado River Authority

Prepared by

December 2015

ENVIRONMENTAL RESOURCE INVENTORY i LCRA MANSFIELD DAM LOW WATER CROSSING RECREATION AREA

TABLE OF CONTENTS 1.0 Introduction ......................................................................................................................................... 1

2.0 Topography ......................................................................................................................................... 1

3.0 Land Use ............................................................................................................................................. 1

4.0 Geology ............................................................................................................................................... 2

5.0 Soils ..................................................................................................................................................... 3

6.0 Hydrology ............................................................................................................................................ 3

7.0 Vegetation ........................................................................................................................................... 3

8.0 Wildlife ................................................................................................................................................ 4

9.0 Federally Threatened and Endangered Species ................................................................................... 5

10.0 Critical Environmental Features .......................................................................................................... 6

11.0 Cultural Resources .............................................................................................................................. 6

12.0 Pollutant Attenuation ........................................................................................................................... 7

13.0 References ........................................................................................................................................... 7

LIST OF APPENDICES

Appendix A. Figures Appendix B. Preliminary Plan Set Appendix C. Photographs Appendix D. Wetland Data Forms Appendix E. LCRA Balcones Canyonlands Conservation Plan (BCCP) Infrastructure Project – Habitat

Assessment Application dated December 2015

LIST OF FIGURES

Figure 1. Location Map on Topographic Base Figure 2. Site Map Figure 3. Geologic Formations Figure 4. Soils Map Figure 5. Hydrology Map Figure 6. City of Austin Water Regulation Zones Figure 7. Wetland Delineation

ENVIRONMENTAL RESOURCE INVENTORY 1 LCRA MANSFIELD DAM LOW WATER CROSSING RECREATION AREA

1.0 INTRODUCTION

The Lower Colorado River Authority (LCRA) has developed a master plan for improving the Mansfield Dam Low Water Crossing Recreation Area. The recreation area is located approximately 1,800 feet downstream of Mansfield Dam on Lake Austin’s southeast bank and is located on the north side of Low Water Crossing Road (see Figures 1 and 2 in Appendix A). The subject property is approximately 41 acres that is primarily bordered by densely vegetated, vacant land owned by LCRA, as well as Lake Austin to the northwest.

The existing Mansfield Dam Low Water Crossing Recreation Area consists primarily of a gravel parking lot that can accommodate approximately 30 vehicles; the recreation area also includes picnic tables, three portable restrooms, and a concrete boat launch ramp. The proposed construction at the recreation area would include an entrance gate and station that will include an automatic exit gate and a new paved turnaround driveway near Low Water Crossing Road and RM 620. Also along Low Water Crossing Road, LCRA proposes to construct a park host site adjacent to an existing circular gravel driveway. Along Lake Austin, LCRA proposes to construct a day-use parking lot that will accommodate approximately 75 cars and a permanent restroom structure with six stalls and an associated on-site sewage facility leach field.

Blanton & Associates, Inc. (B&A) completed this Environmental Resource Inventory (ERI) for LCRA to meet the City of Austin’s Land Development Code (LDC), Section 25-8-121 (A) and Title 30-5, and it is anticipated that this document will be used to help satisfy the City of Austin’s environmental quality requirements. This documentation is based on B&A’s examination of accessible Global Information System (GIS) layers, research of available literature, and fieldwork conducted at the project site on December 14 and 15, 2015. During the site visits, B&A evaluated areas of the proposed property that will be impacted by the proposed project (approximately 1.55 acres of proposed disturbed land). Maps of the proposed project site are included in Appendix A, the preliminary project plans are included in Appendix B, and photographs of the project site are included as Appendix C. Wetland data forms are included as Appendix D, and Appendix E includes a copy of the LCRA Balcones Canyonlands Conservation Plan (BCCP) Infrastructure Project – Habitat Assessment Application dated December 2, 2015.

2.0 TOPOGRAPHY

The subject property lies within the Mansfield Dam, Texas U.S. Geological Survey (USGS) topographic map quadrangle (Figure 1 in Appendix A). The subject property slopes gradually to the west-southwest towards the Colorado River at the western edge of the property. The elevation ranges from approximately 625 feet to 500 feet above mean sea level. Surface water generally travels north and west towards Lake Austin within the subject property.

3.0 LAND USE

Review of historic aerial photographs and topographic maps indicates that the subject property was historically undeveloped and has been used as an informal park and recreation area since the 1960s. According to TxDOT records, the existing bridge that serves as the low water crossing over Lake Austin was constructed in 1938, which is likely when Low Water Crossing Road was constructed. From west to


east, the subject property currently consists of a gravel parking area along the southeast bank of Lake Austin, on the north side of Low Water Crossing Road. Several metal signs are posted along the perimeter of the parking area. Dense vegetation surrounds the parking area. A dirt path leads from the parking area north through the vegetation to a small-craft concrete launch ramp that provides access to Lake Austin upstream of the low water crossing. As shown on the site plans included in the plan set and in the photographs included in Appendix C, there is a small detention feature north of the existing gravel parking lot. Associated with that feature are a wooden dock that extends into the feature, a concrete wall with metal sheeting and electric sensor, and a concrete slab and riprap adjacent to wall. It appears that two sampler wells (identified on the site plans as “monitoring wells”), a metal water tank, a small mechanical metal shed (identified on the site plans as “well house”), a gabion wall, and a concrete flume with wingwalls are all associated with this detention feature. According to a review of high-resolution aerial photographs, it appears that the detention feature was constructed between 1973 and 1985.

Approximately 0.1 mile east of the existing parking area along Low Water Crossing Road is a circular gravel driveway that is proposed as the future host site. It is heavily vegetated and is currently closed to the public. Approximately 450 feet to the east of the future host site is the site of the proposed turnaround driveway. This area consists of open, vacant land.

The area south of the subject property and directly adjacent to Low Water Crossing Road is heavily wooded and undeveloped land owned by LCRA. Other developments and land uses in the area include FM 620 (approximately 0.1 mile north of the proposed turnaround driveway) and Mansfield Dam (approximately 0.25 mile north of the proposed turnaround). The residential subdivisions of Montview Harbor and Montview Acres are located 0.15 mile south of the subject property.

There are no water wells located on the subject property according to the City of Austin’s 2013 GIS layer mapping the city’s water wells.

4.0 GEOLOGY

Two geologic formations are mapped as outcropping in the study area: the Glen Rose Formation (Kgr) on approximately the eastern third of the study area, and Lower Colorado River terrace deposits (Qlcr) on the remainder of the study area (Figure 3 in Appendix A).

The Glen Rose formation consists mostly of limestone, dolomite, and marl subdivided into two units by a Corbula bed, which vary in their resistance to erosion, thereby forming a distinctive stair-step topography. The limestone is aphanitic to fine grained, hard to soft and marly, and a light gray to yellowish gray color. The dolomite is fine grained, porous, and a yellowish brown color. The formation includes marine megafossils that include molluscan steinkerns, rudistids, oysters, and echinoids that are more numerous in the lower layer (about 220 feet thick). The lower part is more massive, about 160 feet thick including the top Corbula bed, and has abundant steinkerns of Corbula harveyi in an interval about five feet thick. The Glen Rose formation overall is approximately 380 feet thick (Bureau of Economic Geology (BEG) 1974).

The Lower Colorado River terrace deposits include sand, silt, clay, and gravel, and are yellow to orange-brown in color (Trippet and Garner 1976).


5.0 SOILS

Three soil units were mapped by the Soil Conservation Service (SCS) on the subject property: Brackett soils, rolling (BlD); Hardeman fine sandy loam, 5 to 12 percent slopes (HaE); and gravel pit (GP) (SCS 1974). Soils in the project area are shown in Figure 4 in Appendix A.

Brackett soils, rolling (BlD) are found in areas with slopes of generally five to 12 percent and on benches typically 100 to 500-ft wide. BlD soils are shallow and the surface layer is a generally a gravelly clay loam. Limestone fragments cover approximately 75 percent of the surface, and rock outcrops are present over approximately 20 percent of the surface area of the soil type. This soil type has a capacity for rapid runoff, is well drained, and is best suited for use as wildlife habitat or rangeland (SCS 1974).

Hardeman fine sandy loam, 5 to 12 percent slopes (HaE) typically occurs on single slopes in long narrow benches above floodplains, generally 20 to 40 acres in size. Hardeman series consists of deep, well-drained soils that develop over old alluvium. The surface layer of Hardeman fine sandy loam, 5 to 12 percent slopes is about 10 inches of brown fine sandy loam. The next layer is light-brown fine sandy loam to about 36 inches in depth. The underlying soil is reddish-yellow silty loam to a depth of about 60 inches. This soil is mostly used for pasture or rangeland (SCS 1974).

A small portion of the subject property was categorized by the SCS (1974) as Gravel Pit, in the area along Low Water Crossing Road (Figure 4).

6.0 HYDROLOGY

The subject property is located within the Trinity Aquifer (Outcrop) and the Lake Austin Watershed, and it is directly adjacent to the Bear Creek West Watershed (Figure 5 in Appendix A). Lake Austin borders the subject property to the northwest, and the surface water within the subject property flows in a north and west direction overland towards Lake Austin. The Federal Emergency Management Agency (FEMA) maps show the western portion of the subject property is located within the 100-year Floodplain (Federal Emergency Management Agency 2015).

The subject property also occurs within the City of Austin Water Supply Rural Zone. Adjacent to the subject property to the north and west, Lake Austin is considered a Critical Water Quality Zone (CWQZ), and adjacent to the subject property to the south is a Water Quality Transition Zone (WQTZ) associated with Bear Creek (Figure 6 in Appendix A) (City of Austin 2013).

7.0 VEGETATION

Vegetation observed in the study area included woodlands in the western portion and savannah in the eastern portion. A tree survey has been completed and is shown on the plan set (see sheets C4 and C16 in Appendix B).

The woodlands in the western portion include plateau live oak (Quercus fusiformis), honey mesquite (Prosopis glandulosa), cedar elm (Ulmus crassifolia), and Texas sugarberry (Celtis laevigata). Trees growing near water included black willow (Salix nigra), American sycamore (Platanus occidentalis), and


cottonwood (Populus deltoids). Non-native woody species observed were wax-leaf privet (Ligustrum japonicum) and chinaberry (Melia azedarach). Ashe juniper (Juniperus ashei) is also common, particularly in the shrub layer. Other shrubs observed were false willow (Baccharis neglecta), Texas persimmon (Diospyros texana), gum bumelia (Sideroxylon lanuginosum), agarita (Berberis trifoliolata), and elbowbush (Forestiera pubescens). Prickly-pear cactus (Opuntia sp.) and twist-leaf yucca (Yucca rupicola) were also present.

Japanese honeysuckle (Lonicera japonicum) was abundant in the western portion of the study area, forming a dense cover over some areas. Other vines observed were saw greenbrier (Smilax bona-nox), southern dewberry (Rubus trivialis), and poison ivy (Toxicodendron radicans).

Grasses observed included King Ranch bluestem (Bothriochloa ischaemum), little bluestem (Schizachyrium scoparium), southwestern bristlegrass (Setaria scheelei), dallis grass (Paspalum sp.), and johnsongrass (Sorghum halepense). Other species noted in the herbaceous layer were Mexican hat (Ratibida columnaris), Texas snakeweed (Gutierrezia texana), and Turk’s cap (Malvaviscus drummondii).

The savannah in the eastern portion of the study area had a generally more open canopy, but was otherwise similar to the woodlands in the western portion. Species composition is mostly similar, but hydrophytic species were absent (e.g., black willow, cottonwood, and American sycamore). Honey mesquite was slightly more common in the eastern portion of the study area.

8.0 WILDLIFE

Wildlife on the subject property is typical of the surrounding area. The following paragraphs identify species that are likely to be present on the property based on their known occurrence in similar habitat in other parts of western Travis County (Kutac and Caran 1994), or that were observed on or adjacent to the tract during field surveys.

Amphibians that are expected to occur in on the subject tract are the Blanchard’s cricket frog (Acris crepitans blanchardii), coastal plain toad (Incilius nebulifer), western narrow-mouthed toad (Gastrophryne olivacea), Rio Grande leopard frog (Rana berlandieri), and cliff chirping frog (Eleutherodactylus marnockii).

Reptiles that are likely to be found in the area include lizards such as the green anole (Anolis carolinensis), six-lined racerunner (Cnemidophorus sexlineatus sexlineatus), Texas alligator lizard (Gerrhonotus liocephalus), Texas spiny lizard (Sceloporus olivaceus), prairie lizard (Sceloporus consobrinus), ground skink (Scincella lateralis), western diamondback rattlesnake (Crotalus atrox), Texas ratsnake (Elaphe obsoleta), coachwhip (Masticophis flagellum), Texas coralsnake (Micrurus tener), rough green snake (Opheodrys aestivus), black-necked gartersnake (Thamnophis cyrtopsis), checkered gartersnake (Thamnophis marcianus), and rough earth snake (Virginia striatula).

Common birds expected to occur on the subject property comprise a large, diverse group. According to data reviewed on the eBird website, 130 species have been reported on the Colorado River below Mansfield Dam, which is the nearest hotspot in the vicinity (eBird 2015). Common species include the turkey vulture


(Cathartes aura), mourning dove (Zenaida macroura), white-winged dove (Zenaida asiatica), chimney swift (Chaetura pelagica), black-chinned hummingbird (Archilochus colubris), yellow-rumped warber (Dendroica coronata), painted bunting (Passerina ciris), summer tanager (Piranga rubra), eastern phoebe (Sayornis phoebe), purple martin (Progne subis), western scrub jay (Aphelocoma coerulescens), Carolina chickadee (Poecile carolinensis), tufted titmouse (Baeolophus bicolor), ash-throated flycatcher (Myiarchus cinerascens), Carolina wren (Thryothorus ludovicianus), Bewick's wren (Thryothorus bewickii), blue-gray gnatcatcher (Polioptila caerulea), American kestrel (Falco sparverius), greater roadrunner (Geococcyx americana), northern mockingbird (Mimus polyglottos), northern cardinal (Cardinalis cardinalis), yellow-billed cuckoo (Coccyzus americanus), red-tailed hawk (Buteo jamaicensis), white-eyed vireo (Vireo griseus), great blue heron (Ardea Herodias), ladder-backed woodpecker (Picoides scalaris), cedar waxwing (Bombycilla cedrorum), lesser goldfinch (Carduelis psaltria), ruby-crowned kinglet (Regulus calendula), and rufous-crowned sparrow (Aimophila ruficeps).

Mammals that are likely to be found in the area include the Virginia opossum (Didelphis virginiana), Mexican free-tailed bat (Tadarida brasiliensis), nine-banded armadillo (Dasypus novemcinctus), eastern cottontail (Sylvilagus floridanus), rock squirrel (Spermophilus variegatus), eastern fox squirrel (Sciurus niger), white-footed mouse (Pero-myscus leucopus), hispid cotton rat (Sigmodon hispidus), gray fox (Urocyon cinereoargenteus), ringtail (Bassariscus astutus), common raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and white-tailed deer (Odocoileus virginianus).

9.0 FEDERALLY THREATENED AND ENDANGERED SPECIES

The following species are federally listed threatened or endangered (or candidates for such listing), with ranges covering Travis County (U.S. Fish and Wildlife Service (USFWS) 2015):

• Golden-cheeked warbler (Setophaga chrysoparia) – Bird, Federally Endangered;

• Black-capped vireo (Vireo atricapilla) – Bird, Federally Endangered;

• Whooping crane (Grus americana) – Bird, Federally Endangered;

• Bald eagle (Haliaeetus leucocephalus) – Bird, Delisted due to Recovery;

• Piping Plover (Charadrius melodus) – Bird, Federally Threatened;

• Barton Springs salamander (Eurycea sosorum) – Amphibian, Federally Endangered;

• Jollyville Plateau salamander (Eurycea tonkawae) – Amphibian, Candidate for Listing;

• Austin blind salamander (Eurycea waterlooensis) – Amphibian, Candidate for Listing;

• Bee Creek Cave harvestman (Texella reddelli) – Arachnid, Federally Endangered;

• Bone Cave harvestman (Texella reyesi) – Arachnid, Federally Endangered;


• Tooth Cave pseudoscorpion (Tartarocreagris texana) – Arachnid, Federally Endangered;

• Tooth Cave spider (Neoleptoneta myopica) – Arachnid, Federally Endangered;

• Warton's cave meshweaver (Cicurina wartoni) – Arachnid, Candidate for Listing;

• Kretschmarr Cave mold beetle (Texamaurops reddelli) – Insect, Federally Endangered;

• Tooth Cave ground beetle (Rhadine persephone) – Insect, Federally Endangered;

• Bracted twistflower (Streptanthus bracteatus) – Flowering Plant, Candidate for Listing; and

• Texas fatmucket (Lampsilis bracteata) – Clam, Candidate for Listing.

The study area does not provide suitable habitat for any of the species listed above, so none of these species is expected to occur there. The study area is in Zone 3 – “Not Known to be Habitat” for the golden-checked warbler. Records for the golden-cheeked warbler and the black-capped vireo were reported by Greg Lasley for the eBird hotspot referred to as “Colorado River below Mansfield Dam” in April 1981, but the precise locations are not known (eBird 2015).

The LCRA has submitted an application to the Balcones Canyonlands Conservation Plan (BCCP) for the proposed project (Appendix E).

10.0 CRITICAL ENVIRONMENTAL FEATURES

As defined by the City of Austin Land Development Code (COA LDC) in Section 25-8-1, critical environmental features (CEFs) include bluffs, canyon rimrocks, caves, faults and fractures, seeps, sinkholes, springs, and wetlands. None of these features is present in the study area.

During the field investigations, B&A staff identified an area that exhibited some of the characteristics of a wetland in the western portion of the subject property, including a shift in vegetation between hydrophytic vegetation and upland plant communities, and standing water (see Photos 9 through 11 in Appendix C and Figure 7 in Appendix A). Upon further inspection, it was determined that the areas did not meet the criteria for wetlands as would be necessary for them to be subject to regulation by the U.S. Army Corps of Engineers (USACE). Wetland evaluation data sheets for three observation points are included in Appendix D.

11.0 CULTURAL RESOURCES

In March 2015, LCRA completed An Intensive Cultural Resources Survey of LCRA’s Mansfield Dam Low Water Crossing Park, Travis County, Texas. This report documented LCRA’s intensive cultural resources survey of approximately 75 acres of LCRA land, which included the 41-acre project area. As part of the LCRA’s findings, six sites were discussed, including two previously recorded sites and four previously unrecorded sites. All sites were determined to have unknown status for formal State Antiquities Landmark (SAL) designation or were recommended as being fully documented and not eligible for formal SAL status.


LCRA cultural resources staff recommended that park development proceed. A copy of this cultural resources survey is available at LCRA.

12.0 POLLUTANT ATTENUATION

According to Section 1.3.4 of the City of Austin’s July 2015 Environmental Criteria Manual, a pollutant attenuation plan is required for all industrial development projects not enclosed in a building. The proposed project does not meet the definition of industrial use and therefore a pollutant attenuation plan is not required for this proposed project.

13.0 REFERENCES

Bureau of Economic Geology. 1974. Geologic atlas of Texas, Austin sheet. Bureau of Economic Geology, University of Texas-Austin. Austin, Texas. 10 pp. and map.

City of Austin. 2013. Buffers, Setbacks, Critical Water Quality Zone, and Water Quality Transition Zone.

Vector digital data, City of Austin GIS data sets. ftp://ftp.ci.austin.tx.us/GIS-Data/Regional/coa_gis.html (accessed December 14, 2015).

City of Austin. 2015. Environmental Criteria Manual (Supplement 7 – 2015; online content updated on July 29, 2015). <https://www.municode.com/library/tx/austin/codes/environmental_ criteria_ manual> (accessed on December 15, 2015).

eBird. 2015. Data for Colorado R. below Mansfield Dam (Travis Co.), Travis, US-TX. http://ebird.org/ebird/hotspots (accessed December 16, 2015).

Federal Emergency Management Agency. 2015. 100-year Floodplain. Vector digital data. http://www.fema.gov/ (accessed December 14, 2015).

Kutac, E. A. and S. C. Caran. 1994. Birds and other wildlife of south central Texas. University of Texas Press, Austin, Texas. 203 pp.

Lower Colorado River Authority. 2015. Balcones Canyonlands Conservation Plan, available from the LCRA Austin office.

NETR Online. 2015. HistoricAerials.com. www.historicaerials.com (accessed on December 15, 2015).

Soil Conservation Service. 1974. Soil survey of Travis County, Texas. U.S. Department of Agriculture. 123 pp. and 83 maps.

Trippet, A. R. and L. E. Garner. 1976. Guide to points of geologic interest in Austin. Guidebook no. 16. Bureau of Economic Geology, University of Texas at Austin. 38pp. and figures.

U.S. Fish and Wildlife Service. 2015. Environmental Conservation Online System (ECOS) species list for Travis County, Texas. http://ecos.fws.gov/tess_public/reports/species-by-current-range-county?fips=48453 (accessed December 16, 2015).

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Project 9.15 An Intensive Cultural Resources Survey of LCRA’s Mansfield Dam Low Water

Crossing Park, Travis County, Texas

By

John W. Arnn

Andrew F. Malof

Matthew J. Larsen

Casey Hanson

and

Daniel J. Prikryl

Andrew F. Malof

Principal Investigator

TAC Permit 7131

Interim Report 10.15

Lower Colorado River Authority

Real Estate Services

September 2015

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MANAGEMENT SUMMARY

In February and March of 2015 the Lower Colorado River Authority (LCRA) conducted an intensive

cultural resources survey of the Mansfield Dam Low Water Crossing Park improvement project. Several

additions and improvements are proposed for this park necessitating a cultural resources review and site

revisits of previously documented archaeological sites as well as the documentation of any previously

unrecorded cultural resources.

The park property consists of approximately 41 acres located immediately south of the Mansfield Dam

along the left bank of the Colorado River (Figure 35). The proposed additions and improvements include

the construction of an entry station, park host site, parking lot and restrooms within existing LCRA

property, and rebuilding an existing fence between the park and neighboring private land to the south

(Figure 36). No hiking trails are planned at this time. Although the park remains designated as 41 acres

out of a total 302-acre parcel, evolving design, based in part on input from members of the public, has

reduced the infrastructure and activity footprint to about 12 acres immediately adjacent to the Colorado

River (Lake Austin) and less than an acre set aside for a park host site along the entry road. An additional

34 acres was surveyed based on preliminary park plans, for a total survey area of approximately 75 acres.

All present development is within areas previously disturbed by dam construction, or, in the case of the

park host site, at the base of an upland ridge with shallow soils.

Two previously recorded sites, 41TV525 and 41TV527, were revisited and reassessed. Four previously

unrecorded sites, 41TV2481-41TV2484, were documented. Site 41TV525 was described previously as a

minor lithic procurement site. The present investigations determined the site has deeply buried prehistoric

cultural material. Site 41TV527 was previously documented as an early twentieth century homestead and

minor prehistoric lithic scatter. The present investigation confirmed these observations, but also

uncovered the potential for buried prehistoric components. Site 41TV2481 is an early- to mid- twentieth

century homestead associated with the Fritz and Fannie Hughes ownership. It also has a minor prehistoric

lithic scatter. Site 41TV2482 is a prehistoric open camp with a burned rock midden located on Bear

Creek, well outside any presently proposed improvements. The site has suffered from looting activities.

Site 41TV2483 consists of a pair of small cement structures used for explosives storage, almost certainly

dating to the time of dam construction. Site 41TV2484 is the ruined foundation of Cooper’s Bait Shop, a

local institution during the latter part of the twentieth century.

As discussed below, sites 41TV525 and 41TV527, or portions thereof, are recommended as having

unknown status for formal State Antiquities Landmark (SAL) designation. Site 41TV2482 is considered

to be eligible for formal SAL status as a threatened site. Sites 41TV2481, 41TV2483 and 41TV2484 are

recommended as being fully documented and ineligible for formal SAL status.

All work was conducted under the terms of and in accordance with LCRA’s annual blanket State

Antiquities Permit Number 7131 issued to the LCRA under the terms of the Memorandum of

Understanding between the LCRA and the Texas Historical Commission (THC). There is no federal

funding or permitting involved that requires a Section 106 review. No artifacts were collected during the

survey.

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Figure 35. Location of project area on Mansfield Dam USGS quad.

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Figure 36. Consultant’s representation of park improvements.

ENVIRONMENTAL BACKGROUND

The survey area is located on the Edwards plateau on the western edge of Travis County along an inside

bend of the Colorado River immediately below Mansfield Dam. The park acreage is composed primarily

of gently sloping terraces along the Colorado River and Bear Creek. However, there are areas of abrupt

topographic relief located along Bear Creek and parallel to the river due to dam construction.

The survey area is underlain by Quaternary geology (Pleistocene age) consisting of mudstone, limestone,

dolomite, and shale. Parent soil material was formed in plains outwash (Barnes 1976).

Soils in the proposed project area are mapped primarily as Brackett-Rock outcrop complex, described as

gravelly clay loam and clay loam on 1 to 12 percent slopes, and Hardeman fine sandy loam on 5 to 12

percent slopes. Brackett-Rock outcrop complex is found on ridges with depth to bedrock varying between

18 and 48 inches. Hardeman fine sandy loam occurs on stream terraces as a fine sandy loam from 0 to 36

inches and as a silt loam from 36 to 60 inches. In terms of area the next most prevalent soil is Brackett-

Rock outcrop-Real complex on 8 to 30 percent slopes and described as gravelly clay loam found on

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ridges with a depth to bedrock varying between 14 and 60 inches. Approximately 12 percent of the

project area is classified as gravel pits and, thus, considered profoundly disturbed with little or no

potential to contain intact buried cultural deposits. Finally, Altoga silty clay, 3 to 6 percent slopes,

represents approximately seven percent of the project area and varies from moderately eroded silty clay to

a silty clay loam found on stream terraces (Web Soil Survey 2015).

The proposed project area lies in the Balcones Canyonlands Ecoregion of Texas, with vegetation types

characterized by Live Oak-Ashe Juniper Parks (Figure 37). In the absence of any agricultural and range

management much of the area has become overgrown with dense stands of juniper, white brush or bee

brush, and poison ivy. Live oak, mesquite, pecan, black walnut, Chinese tallow, and Chinaberry trees are

also present in small numbers.

According to documents in the LCRA archives, in 1937 Fritz Hughes described land use within his

former 320 parcel as 40 acres in cultivation, 30 acres in brush, and 250 acres in pasture. This description

is also supported by an aerial photo taken shortly after the construction of the dam in which at least two

large fields (possibly cultivated), several structures, and a garden are clearly visible in the project area.

Although it is uncertain if this property was historically utilized in the same fashion, it is clear from the

height and density of trees and brush present today that since the removal of the house, barn, and

outbuildings in the 1980s, the entire property has been fallow.

Figure 37. Typical woods/parks setting in project area.

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PREVIOUS INVESTIGATIONS

The first archaeological investigations in the area around Mansfield Dam were conducted in the 1930s in

association with the construction of the dam itself, then known as Marshall Ford Dam. Once the dam was

completed in 1941, there were few investigations until the 1980s, when suburban neighborhoods, and

their attendant infrastructure, began to be developed; a trend which has continued and intensified since.

500

In the Mansfield Dam Low Water Crossing Park (MDLWC) project area itself, there are three previously

recorded sites. In 1980, LCRA hired Prewitt & Associates, Inc. to conduct an archeological survey of the

project area in advance of planned brush clearing (Kotter 1980). The survey was conducted by Steven

Kotter on the 24th of September and resulted in the recordation of two prehistoric sites, 41TV25 and

41TV526, and one multi-component site, 41TV527.

Site 41TV525 is a lithic procurement site located on an upper ridge slope approximately 150m southeast

from the Colorado River channel and consisting of cortex flakes and battered cobbles. Kotter described it

as “surficial and thinly distributed” (Kotter 1980), requiring no further investigation.

Site 41TV526 is a 10mx20m site situated upslope from and north of Bear Creek, a tributary on the left

bank of the Colorado. At 41TV526 Kotter found scattered burned rocks, several interior flakes, and

mussel shell, which was surficial and disturbed by a road (Kotter 1980).

Site 41TV527 is a multi-component site roughly 400m east of the Colorado, also upslope from and just

north of Bear Creek. The historic component artifacts recovered consisted of possible foundation stones

for a structure and scattered metal, glass, and ceramics, all of which are consistent with a farmstead dating

to the early to mid 20th century. The prehistoric artifacts consisted of a light lithic scatter, possible burned

rock, and a distal tip biface fragment. The report described the site as “apparently surficial; does not

contain a high information yield potential” (Kotter 1980). In 2013, LCRA cleared vegetation as part of a

fire break lane, which ran through 41TV527.

In the project area, surveys were conducted for the construction of a 1300-ft fence in 1977, and for the

installation of a subsurface water pipeline for the nearby Montview subdivision in 1992. Neither survey

yielded any sites.

Given that there are only three recorded sites in the Mansfield Dam Low Water Crossing Park project

area, it may be useful to explore some of the archaeological sites in the wider vicinity.

In the 1930s, the WPA, with the University of Texas, recorded a number of sites in relation to the

construction of Mansfield Dam. The sites near the dam were mostly prehistoric open campsites or burned

rock middens (BRM), most of which are now submerged under the Lake Travis reservoir pool (elevation

681 ft AMSL).

Site 41TV32, located m offshore from Hudson Bend, consisted of three burned rock middens

(BRMs) 75-100 ft in diameter and 3-4 ft high, with lithic tools, mussel shell and faunal remains found in

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association. Site 41TV36, now submerged just northeast of Sometimes Island (known as Horseshoe Bend

before being inundated), is located near a large spring and encompassed ten burned rock middens, also

with lithic tools and mussel found associated. 41TV207 is an open campsite, where debitage, mussel

shell, and quartzite manos were found near the mouth of a small stream, all of which is also now

submerged.

Site 41TV31 is a BRM site just above the Lake Travis reservoir pool. Located in the north portion of

Mansfield Dam Park, which is leased to and run by Travis County, 41TV31 was revisited in March of

1998 during a survey of the park, ahead of a park improvement project. It was decided in 2000 to cap

41TV31 with sterile fill to protect the site.

Between 1941 and 1980, only two sites were recorded in the near vicinity of the MDLWC project area. In

1968, in the Apache Shores subdivision, site 41TV121, a BRM 100x60 ft, was bulldozed through its

center before it was examined, revealing mussel shell and lithic tools, including a Travis point and plano-

convex scrapers. This site is 1.5km west and across the Colorado River from the MDLWC project area. In

1970, 41TV179, a borrow pit in an alluvial terrace 1 km southwest of the MDLWC project area, yielded

mussel shell, burned rocks, faunal remains, and lithics, including a possible Nolan point.

From 1985-1988, surveys were conducted by Espey, Huston, & Associates of the new Steiner Ranch

subdivision yielding several sites. Sites 41TV1227-41TV1230 are lithic scatters and open campsites, as

well as one historic dump, located between 1 and 2 km east of the MDLWC project area along Bear

Creek. Site 41TV1403 is an open campsite and burned rock hearth 500 m east of the MDLWC project

area, where cores, lithic tools, debitage, and a projectile point were found, centered around the hearth

feature. Site 41TV1234 and 41TV1235 are both historic house sites 700 m to 1 km south of the MDLWC

project area. Site 41TV1233, situated 1.4 km southeast of the MDLWC project area, is a historic

cemetery, consisting of four children of the Hancock family, buried between 1900 and 1912 (Voellinger,

1986).

In 1988, several open campsites and two BRM (sites 41TV1385-41TV1388) were recorded at Windy

Point, 3 km north of the MDLWC project area; artifacts included: lithic tools, debitage and an Ensor-Frio

dart point.

During the aforementioned 1998 Mansfield Dam Park improvement project survey seven other sites were

recorded, numbering 41TV1837-41TV1843. Site 41TV1837 is the site of a house built in 1946, and

which burned down in the 1980s. Sites 41TV1838-41TV1843 are all lithic scatter sites near a small

drainage into the Colorado River and within 400 m of the BRM at 41TV31. The sites generally had

flakes, lithic tools, and mussel shell fragments. The sites are an “indicator of, rather than locus of

prehistoric activities” (Malof and Prikryl 1999:71) and indicate a wider area was in use than previously

thought. Site 41TV1842 was the westernmost site in the survey and yielded an end scraper, possibly

indicative of the Toyah, perhaps dating this site to the Late Prehistoric. This area would have provided

occupants an excellent vantage point over Horseshoe Bend, a narrow jut of land formed by a meander of

the Colorado River (Malof and Prikryl 1999). These sites were determined to have little further research

value, as there was no real vertical or horizontal deposition.

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In 1999, also at Mansfield Dam Park, a concrete foundation was uncovered 45m northeast of the dam and

determined to have been part of the dam construction project. In the same year, LCRA Cultural Resources

staff surveyed the area east and northeast of the MDLWC project area along Bear Creek in the Steiner

Ranch property and recorded two open campsites (41TV1402 and 41TV1403), one in association with a

BRM, finding lithics and a projectile point.

In 2004, LCRA archaeologists surveyed along the T-160 electrical transmission line, east of the MDLWC

project area, before maintenance work conducted on the line. They revisited 41TV1227, a lithic scatter

previously recorded by Espey, Huston & Associates. Investigators also recorded 41TV2109, a lithic

scatter consisting of debitage, burned rock and ground stone, which may be a part of 41TV1228.

In 2006, Jerry Henderson, a private contractor, conducted several shovel tests at the North Shore Water

Treatment Plant, and recorded a multi-component site, 41TV2182. This site encompasses the remains of a

government workers’ camp erected for the construction of the dam. The prehistoric component was a

lithic scatter, which yielded a Uvalde and a Nolan dart point.

In 2011, the water levels in Lake Travis were low enough to allow a survey on Sometimes Island, where

both historic and prehistoric sites were recorded. 41TV2399 is a historic site of concrete piers and

counterweights from the tramway system used in the construction of Mansfield Dam. These were

removed after investigation as they posed a boating hazard. Site 41TV2401 is a prehistoric campsite

where investigators found moderate to dense mussel shell, burned rocks, and debitage. This site sits

submerged 40’ below the normal Lake Travis pool elevation.

In 2013, Lake Travis water levels remained low, allowing LCRA Cultural Resources employees to record

a historic farmstead (41TV2446) with a cistern on the north shore of Horseshoe Bend and a historic site

(41TV2443) related to dam construction including concrete slabs, as well as cigarette and newspaper

vending machines.

The historic sites recorded in the vicinity of the Mansfield Dam Low Water Crossing Park project are

generally small farmsteads from the late nineteenth to mid twentieth centuries or part of the massive

construction effort of building the dam, which dominates the recent archaeological record in this area.

The prehistoric sites are mostly open campsites, lithic scatters and burned rock middens. Artifacts from

these sites range temporally from the Early Archaic to the Late Prehistoric periods and likely into the

Historic era as well.

METHODOLOGY

The survey was designed to identify unrecorded archaeological sites and assess them and the two

previously recorded sites for potential status as State Antiquities Landmarks. An intensive archeological

survey was carried out within the 41 acres designated for park and another 35 acres which may see future

use, excluding areas that were previously scraped bare by dam construction related activities (Figure 38).

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Adjacent high probability areas along Bear Creek that might be affected by future hiking trails were also

assessed.

The assessment consisted of a pedestrian survey (walking over the property and inspecting the ground for

cultural material) and subsurface excavations. A total of 54 shovel tests were excavated in areas where

archeological sites were previously recorded, surface visibility was poor and the potential for buried

cultural material existed (e.g. undisturbed level terraces with intact soils). In general, ground visibility

was observed to be good at about 75 percent. Therefore, shovel tests tended to cluster in the footprint of

previously recorded sites and along terraces of Bear Creek. The number of shovel tests exceeds the

suggested standard for a project of this size. Figure 55 illustrates the locations of all shovel tests.

Shovel test locations and other spatial data was collected on GPS and transferred to a GIS. Other records

included photographs, field notes and field-based sketch maps. Archival research was conducted at

LCRA’s Central Files and online. Site sketch maps with shovel test locations are at the end of this report,

and shovel test information can be cross-referenced with the table attached as an appendix.

Figure 38. 1945 imagery of Mansfield Dam. Note construction impacts below dam and south/southeast of LowWater Crossing Bridge. Looking northeast. Photo courtesy of LCRA Archives.

RESULTS OF INVESTIGATIONS

Two previously recorded sites, 41TV525, previously described as a prehistoric lithic procurement site,

and 41TV527, a historic homestead and prehistoric lithic scatter were revisited and reassessed. Four

previously undocumented sites were recorded. Site 41TV2481 is the Fritz and Fannie Hughes homestead,

dating to the 1920s, which overlies a minor prehistoric lithic scatter. Site 41TV2482 is a prehistoric open

camp and apparent burned rock midden located on Bear Creek, well outside any planned park

development areas. Site 41TV2483 consists of two small cement structures used to store explosives

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during construction of Mansfield Dam. Site 41TV2484 is the foundation of a bait shop that was in

operation from between perhaps the 1950s until the mid 1980s. Of these six sites, three, 41TV525,

41TV527, and 41TV2482 are considered to have deposits of unknown eligibility for SAL status. Sites

41TV2481, 41TV2483 and 41TV2484 are considered to be fully documented and ineligible for formal

SAL determination. Figure 39 illustrates the sites that were investigated.

Archival Summary

Research conducted at the LCRA archives revealed a continuous chain of title abstracted from Travis

County Deed Records. Beginning in 1859 this property was first assigned to Elzey Stockton from the

John Choate Survey, changing hands to R.W. Riley in 1862, from Riley to Hiram Hartson in 1866, and

from the Hartson family to the last private owners, Fritz and Fannie Hughes, in 1934. LCRA acquired the

property in 1936 shortly before construction of Mansfield Dam began. The section below summarizes

information from census and deed records, newspapers, books and other online sources and is relevant to

sites 41TV527 AND 41TV2481.

Figure 39. Location of archaeological sites in project area.

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John Choate and Elzey Stockton

The 320-acre Choate Survey, which includes the entirety of the proposed park development, was granted

to John S. Choate and his assignee Elzey Stockton by a preemption deed dated in March, 1854. An

affidavit associated with the grant states that Choate and Stockton had both resided on the parcel and had

farmed it, making them eligible for receiving the previously unoccupied public domain, a program which

had been in effect between 1845 and 1854 (General Land Office 2015). U.S. census records show a John

S. Choate (age 45), wife Lucinda and four children residing in Tennessee in 1850. In 1860 the family is in

Titus County, Texas. A Benjamin Choate (Choate – age 35, born in Tennessee) witnessed some of the

documents, and was living in Travis County in 1850. The interpretation is that Benjamin Choate enticed

his older brother to Texas, where John Choate took up residence on the land in question.

An Elzey Stockton from Shelby County, Texas (approximately 200 miles east/northeast of this site)

appears on a list of petitioners from Milam County (approximately 40 miles northeast of this location),

Texas requesting the United States Congress to move Indian trading posts beyond the Texas frontier in

1846 (Texas GenWeb 2015). Elzey Stockton appears again on the 1850 census from Henderson County,

Texas (approximately 150 miles northeast of this site) indicating he was a farmer living on property

(valued at $320) with his wife, four children (three boys age 2, 7, 9 and one girl 4), and another woman

(U.S. GenWeb 2015).

He is not found on 1850 census records, although he is listed as a signatory on an 1846 petition requesting

the U. S. government move Indian trading posts westward from Milam and surrounding counties. In

1860, E. Stockton and wife Ann, both 39, along with their nine children, are listed in the Merriltown

District of Travis County. By 1868 they had moved to California, where Elzey Stockton is found on

voting rolls.

R. W. Riley

In 1859, the Choate survey was patented to Stockton, who sold to R. W. and Sarah M. Riley in 1862.

Choate’s time in Travis County was therefore relatively short-lived, from after 1850 to sometime prior to

1860. An R.W. Riley is shown on the 1860 census as a single 23-year-old attorney from Illinois living in

Llano. In 1861 Riley formed the Llano State Guards a county militia company created for protection

against Indians (Crutchwilliams.com 2015). This type of militia was common throughout many parts of

Texas during this period as many frontier forts were abandoned and/or under strength due to the personnel

demands of the Civil War (Crutchwiliams.com 2015). According to an article in the Llano News, Riley

became a Captain in the Llano State Guard and was responsible for sending out patrols and scouting

parties. Riley also shows up on the roll for the 1st Regiment, Reserve Militia: Company H (Capt. R. W.

Riley), in December 31, 1870. This is probably the same R. W. and Sarah Riley who in 1880 is listed as a

married farmer in Travis County. Riley sold the property in 1866 to Hiram Hartson.

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Hiram Hartson

Hiram Hartson was born in Ohio in 1838 and moved to Texas in 1857 (Find A Grave 2015). He

purchased the Choate Survey for $800. Census records from 1870 show him, apparently widowed with

five children, in Austin. In 1880 he is in Travis County with a new wife, Mary Alice and two young

daughters. In 1900 he is in the Precinct 4 (McNeil) area, as well as in 1910, when a precinct map suggests

the property in question is in Precinct 7. Hartson is also shown in Austin on Bull Creek Road in 1910,

indicating double residency. Also, in 1900, he appears to be neighbors with Emery Hughes, whose

nephew Fritz later purchased the Choate Survey. By 1920, the Hartsons were divorced, with Mary Alice

living on Avenue C in Austin. Hiram Hartson died in 1920 near Teck. He was found in his front yard

dead at the age 81 of an apparent heart attack, according to his death certificate.

Fritz Hughes

Claud Hartson, Hiram’s son, sold land containing the park property to Fritz Hughes in 1922, although the

sale was not formalized until 1934. The abstracted title on file at LCRA indicates Hughes and wife Fannie

“homesteaded” the property in 1933, and in a letter from 1968 referencing a property dispute mentions his

“old homestead.” In 1937 improvements included a “box house,” barn, fences, a cistern valued at $100,

40 acres in cultivation, 30 acres in brush and 250 acres in pasture, as well as a young pecan orchard. In

condemnation proceedings he claims he paid or invested over $9,000 in the property. LCRA had offered

him $4,500, and he was asking $20,000. The difference was eventually split.

Fritz Hughes was the nephew of John R. Hughes, a well-known Texas Ranger (Parsons 2011). Emery

Hughes, as mentioned above, was a neighbor of Hiram Hartson. John and Emery had started a horse

Ranch in western Travis County known as the Long Hollow Ranch, which was apparently a successful

enterprise. Emery married Selma Bastain in 1882, and their children including Tom and Fritz. Travis

County has parks named for Selma, Fritz and Tom. The parks may be on donated land. As a side note,

John Hughes shot himself at the Austin home of his niece in 1947, at the age of 92 (Parsons 2011, p. 285).

Discussion

A 1938 aerial photo (LCRA archive file #WOO395) shows at least two structures and, perhaps, two or

three smaller structures and two roads present on the former Hughes property (Figure 40). The two largest

structures appear to be a shed barn (backing Low Water Crossing Road) and a residence. According to the

court documents filed in Travis County in 1936, Hughes listed several improvements he made to the 320

acre property between 1934 and its acquisition by LCRA 1936. Among the listed improvements is a barn,

house, and fences—all of which are clearly visible in the 1938 aerial.

There are two structures located on the Choate Survey on the 1896 Austin USGS quad. When

georeferenced, one structure’s location corresponds very well with the location of 41TV527. The other’s

is located underneath Mansfield Dam. The 1936 topographic map shows only the Hughes homestead

(41TV2481 - Figure 41), as does a 1959 1:62,500-scale topographic map of Lake Travis. However, in

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1968, 1973 and 1984 USGS maps structures are seen at both the Hughes place and at 41TV527, and in

1973 two outbuildings have been added in the vicinity of the Hughes place, but are gone by 1986.

The evidence indicates that 41TV527 was occupied in the 1850s by either John Choate or Elzey Stockton.

R. W. Riley may have lived there during the Civil War years. The Hartson era, from 1866 to 1922,

probably saw occupation by the Hartson family, although census data is ambiguous, and it is possible

they lived elsewhere and rented or otherwise managed the property. The Hughes place (41TV2481) was

probably built in the early 1920s. A smattering of early artifacts, (a piece of blue featheredge, a hand-

wrought carriage bolt) are probably the result of curated materials.

Figure 40. 1938 photo showing the Hughes homestead. Courtesy of LCRA Archives.

The fact that there is no structure mapped at 41TV527 in 1936 is curious, as these maps were highly

detailed and very accurate. A local resident mentioned that a hunting cabin had been located in the

vicinity of 41TV527, so it is possible that the site had been reestablished, probably by LCRA employee

Ed (Emmett Edwin) Hamilton, who leased the Hughes place after LCRA acquisition up until shortly

before the house was demolished in the mid 1980s. A historically diverse artifact assemblage at 41TV527

supports this interpretation.

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Figure 41. 1936 topographic map with project area overlaid. Note Hughes farmstead in center.

Archaeological Summary

41TV525 (Figure 49)

Site 41TV525 is located on a terrace of the Colorado River in the northernmost portion of the survey area

closest to Mansfield Dam. Much of the western edge of this terrace is bounded by an eroding bank that

falls to a lower terrace immediately adjacent to the Colorado River. To the east the terrace on which the

site is located rises gently into limestone bedrock outcrops. The north portion of the site is bounded by the

Mansfield Dam substation, and the south is bounded by Low Water Crossing Road. Although this site

was described by Kotter (1980) as a small prehistoric lithic procurement site with “surficial and thinly

distributed” cultural materials, the results of the 2015 survey indicate at least one, and possibly two,

buried prehistoric component(s).

Beginning approximately one meter below the terrace surface, several mussel shells, chert flakes (both

primary and secondary), terrestrial snail shell, and a concentration of fire cracked rock were clearly

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visible (Figure 42). Of the eight shovel tests excavated at this site only two contained definitive

prehistoric artifacts (chert flakes), however, most of the other shovel tests contained possible prehistoric

cultural material (chert chunks and/or shatter, burned rock, mussel shell) and several contained primarily

historic refuse (e.g. metal fragments, wire, clear and brown bottle glass, and half a horseshoe) primarily

between 0-20 cmbs. Three of the four positive shovel tests were excavated in the northwest portion of the

site in the terrace east of the cutbank where the exposed cultural material was observed and the fourth

shovel test was excavated in the eastern portion of the site.

Figure 42. Possible hearth feature approximately one meter below surface, along with mussel shell, chert flakes,terrestrial snail shell, and pieces of fire cracked rock eroding from the cutbank.

Surface observations along the eastern boundary of this site revealed exposed bedrock indicating an

extremely shallow depositional setting and observations of surface artifact frequencies were generally

consistent with the light surface scatter of lithic material observed during the 1980 survey. Of the three

shovel tests excavated in the southeastern portion of this site, only one contained artifacts. Shovel Test 50

was excavated to a depth of 85cmbs and contained half a horseshoe in Level one, mussel shell in Level

two, and a single flake each in Levels three, four, and five. Although the vertical and temporal

distribution of artifacts in ST-50 suggests deeply buried intact cultural deposits, the absence of artifacts in

surrounding shovel tests as well as the observation of surficial bedrock in the eastern portion of the site is

puzzling.

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Observations of the surrounding terrain, aerial photos, as well as the soils survey for this area indicate that

this site straddles two different elevations, landforms, and two different soil associations, Brackett and

Hardeman (Werchan et al. 1974).

While Hardeman soils (HaE) are deep well drained soils on top of older alluvial soils found along narrow

benches above flood plains, Brackett soils tend to be shallow and benched between outcroppings of

underlying bedrock. In fact, this latter situation is readily visible on the surface in the easternmost

portions of site 41TV525. Outcroppings of bedrock divided by bands of vegetation growing in these

benched Brackett soils are easily visible in aerial photos of the surrounding terrain. When combined these

data suggest that site 41TV525 was likely much larger in the past extending from pockets of Brackett

soils benched among exposed bedrock in the east portion of the site west on to what was once a much

broader terrace of Hardeman soils. This terrace has experienced significant disturbance due to periodic

flooding of the Colorado River and down-slope erosion from adjacent higher elevations resulting in

scouring and outwash of the western portion of this site.

41TV527 (Figure 50)

This site is located approximately 700m south of the Mansfield Dam Power Plant. It is lies on the north

(right) bank of Bear Creek and is bounded to the east by Fitz Hughes Park Drive and to the north by Blue

Jay Lane. The site is situated on a structural terrace approximately 15 m above a large deep pool in Bear

Creek (Bear Creek is deeply incised at this point in the drainage). The terrace and surrounding area is

covered by dense stands of juniper with occasional oaks and very little underbrush and begins to rise

slightly in elevation as one moves further north.

Beneath the juniper tree cover ground visibility was generally good and concentrations of historic refuse

and cut stone blocks, indicating the former location of an historic residence, and chert flakes and mussel

shell, indicating a former prehistoric campsite, were clearly visible. Based on these surface observations

twelve shovel tests were excavated and cultural material was observed in eight of the twelve shovel tests.

Historic artifacts (e.g. pieces of metal, glass, and a bottle cap) were only recovered in the upper 20 cm of

three shovel tests. More than half of all shovel tests excavated during the site revisit contained prehistoric

artifacts (chert flakes) that appeared to be concentrated in the southern portion of the site.

Although recovery of prehistoric artifacts was also greatest near the surface (upper 40 cm) some recovery

occurred between 40 and 80 cm. One possible prehistoric feature was observed, a concentration of fire

cracked rock in Shovel Test 17 which was excavated within the only historic feature observed—a small

structure consisting of 1.5 x 2 ft metal panels propped up with large stones. This feature was at and just

above 20 cm (Figure 42).

The historic portion of site 41TV527 is represented primarily by a concentration of early twentieth

century refuse. “Clabber Girl Double Acting Baking Powder” cans were observed, numerous (dozens) of

tobacco tins, sardine cans, paint cans, white ware with various impressions (e.g. fish-scale), whiteware

polychrome floral pattern, glassware (much of it solarized), a Jergens lotion bottle, and flat as well as

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bottle glass (all clear) scattered over the surface of the southern portion of the site. These artifacts are

consistent with items used in a residential context (e.g. food preparation, dining, recreation, and toiletry).

At the center of this historic refuse scatter there is a concentration of several (six to eight) large (30cm x

25cm) cut stone blocks that may represent foundation stones for a structure, possibly a house that is no

longer present at this location. This is observation is consistent with the USGS Mansfield Dam 7.5 minute

topographic map depicting a structure at this approximate location. Kotter (1980) also noted large stone

blocks and concluded a structure was once present at this location but was moved sometime prior to his

survey.

Approximately 7 m northwest of the cut stone block concentration is a deer stand. Approximately 10m

west of the cut stone block concentration and just 3m from the deer stand is a structure 1.5m x 1.5m

square constructed of stone blocks supporting irregularly cut panels of sheet and corrugated metal. At

least one piece of corrugated metal panel appears to have been a portion of a tin roof with a hole cut in it

for a stove pipe. The other metal panels could not be identified but all material associated with this feature

could have been constructed from the remnants of a late nineteenth century to early twentieth century

residential structure. The burned wood, metal panels and stone block also suggest it may have been used

as some sort of thermal feature, perhaps a field expedient hearth for hunters. Although the purpose of this

historic feature is unclear, it’s condition and location next to the tree stand suggest very later human

activity, perhaps mid twentieth century, at this site.

Figure 43. Photo of ST-17 showing a buried concentration of fire cracked rock exposed in the wall of the excavationunit.

The historic component of this site may date to the 1850s, but has suffered from overprinting that would

make any archaeological work supporting the archival investigations difficult. The historic component is

not considered to be eligible for formal SAL status. The prehistoric component, however, may have intact

features, particularly to the southeast near Bear Creek. The prehistoric component is considered to be of

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unknown status for formal SAL designation. There are no expected impacts to the site from park

development.

41TV2481–The Hughes Homestead (Figure 51)

This is a historic homestead with a minor prehistoric component. The prehistoric component consists of a

few pieces of lithic debitage found in shovel tests. The site is within mapped Brackett rock outcrop soils,

although the actual soil more closely resembles Hardeman series. Vegetation consists of tall grass and

scattered oak and other trees, as well as various cacti and shrubs. The area is clearly reclaimed pasture.

Features reconstructed from the 1936 topographic map show a barn-like structure to the north, a smaller

outbuilding near the site center, and the primary house to the south (Figure 44). These structures are

confirmed by 1930s aerial imagery (see Figure 40).

Eighteen shovel tests were placed across the site, focusing on the structure locations and to define the

prehistoric component. Only seven of the tests were positive for cultural material. Recovery consisted of

standard mid-twentieth century debris along with a very small amount of prehistoric lithic debitage. Two

pieces of blue featheredge ceramic and an apparent hand-forged spike were exceptions but based on

archival information do not appear to represent an earlier occupation and are more likely to be pieces of

inherited materials.

The northern barn was of simple shed construction with an extended porch. It is possible it was once a

residence. The central structure is not visible in aerial or other images, but is assumed to be a relatively

minor structure. The house was of box-form board-and-batten, pyramidal-roofed construction. The house

was standing until the 1980s when LCRA employee Ed Hamilton stopped leasing the house from LCRA.

Shortly after, it was demolished due to its poor condition.

As discussed above, the earliest occupation of the park tract was either by Elzey Stockton, R. W. Riley, or

their designates, at 41TV527. There is some possibility the Hartsons occupied this site, perhaps at the

northern barn location, however the statement by Fritz Hughes regarding his “homestead” suggests he is

responsible for the development here. This is further supported by 1896 map evidence, which does not

show structures at this location.

During the pedestrian survey two concrete slabs were uncovered just south of Low Water Crossing Road,

immediately south of the fence line, and approximately half way between Fritz Hughes Barn and the old

access road to the subdivision. These slabs are directly beneath a large live oak tree, perhaps the largest in

the area, and surface inspection revealed cut stone blocks, sheet metal panels (perhaps engine

compartment covers), and other mid-late twentieth century refuse. The largest slab is located on the east

side of the Oak tree and measures 32 x 44.5 ft with the long axis aligned to magnetic north/south. The

northwest corner of the slab begins approximately 2 ft north of the fence line into the right-of-way for

Low Water Crossing Road. This slab has ramped edges along the north side and a ramped edge extending

from the north side south along the west side for 20 ft. The smaller slab is located on the west side of the

oak tree, approximately four ft south of the fence line, and measures 12 x 18 ft. The long axis of this slab

is oriented approximately north/south (approximately 10 degrees off magnetic n/s) with straight edges.

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The purpose of these slabs is unclear, although the ramped edges and likely engine compartment panels

suggest they may have been related to mechanic activities. This is supported somewhat by aerial photos

from 1940 and 1951 indicating roads leading directly to and vehicular activity around the large oak tree.

However, due to tree cover, no structures are visible in these aerial photos. The aerial photos also

document a general decline through time in agricultural activity that corresponds with a decline in

vehicular activity around the live oak tree suggesting it is likely that these slabs were related to operations

on the Fritz Hughes farm/ranch. Based on their location adjacent to the road, the vehicular activity evident

in the aerial photos, ramped edges on at least one slab, and their location immediately beneath the largest

tree in the area, it seems likely that these slabs could quite literally have been associated with a “shade

tree mechanic” operation. Even if these slabs were never covered they would have provided a stable work

surface and the limbs of the oak tree would have provided shade as well as support for hoisting relatively

large heavy objects (e.g. small motors).

Figure 44. 1983 photograph of the Hughes house, shortly before its demolition.

Both components of this site are considered to be fully documented. The prehistoric component is a

minor, buried lithic scatter perhaps associated with 41TV525 to the north. The historic component lacks

structural integrity and is unlikely to produce archaeological data that would enhance what is already

known about the site through archival data. The site is not considered to be eligible for formal SAL status.

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41TV2482 (Figure 52)

Site 41TV2482 is located on a landform overlooking Bear Creek, 730 m east of the Colorado River and

120 m south of Low Water Crossing Road. Bear Creek generally runs east to west and the site is located

approximately 50 m north of the creek on a gently sloping landform leading to the creek and bordered by

a steep incline to the north. Vegetation in the area includes post cedar, hardwoods, and short grasses

lending to good ground visibility (70 percent or better). Soils in the vicinity of Temp Site 1 are composed

of a shallow to moderately deep (15-50 cm) zone of silty clay loam zone overlying limestone bedrock.

LCRA archaeologists initially recognized the site due to evidence of looting activities that included

excavated pits, large back dirt piles, discarded screens, a broken shovel, and a broken hand tape (Figure

45). The site appears to be a heavily looted burned rock midden measuring approximately 30 m x 35 m

composed of fire cracked limestone and chert with a high concentration of mussel shell and chert

artifacts. Cultural materials on the surface and in the backdirt piles included chert flakes and core

fragments, but no formal tools were observed.

Figure 45. Central portion of 4TV2482

Looting activities at are centralized in two areas on the south side of the feature and consist of a single

looter’s pit that measures about 2 m x 2 m and a large concentration of pits and back dirt piles that

measures approximately 10 m x 10 m. LCRA archaeologists performed five shovel tests to examine the

depth of the feature and delineate the site’s boundaries. Shovel Test 32 was placed between the two

looting activity areas and attempted to assess the depth of the burned rock midden. Shovel Test 32

revealed a shallow (15 cm) zone of silty clay over limestone bedrock that contained five burned limestone

rocks and two mussel shells. Shovel Test 33 was placed approximately 7 m west of the single looter’s pit

to locate the western boundary of the feature. The shovel test was excavated to a depth of 32 cm and

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revealed two zones of silty clay loam over limestone bedrock and no cultural materials. Shovel Test 34

was located approximately 30 m north of the burned rock midden, and excavation revealed two zones of

silty clay loam totaling 53 cm over limestone bedrock. One burned rock limestone and one mussel shell

fragment were recovered from the top 20 cm of the shovel test. Limestone bedrock outcrops

approximately 5 m south and 5m east of the burned rock midden defined the respective boundaries of the

site, and a sketch map utilizing these data was made in the field. The site was revisited after the initial

discovery and one more shovel test (54) was placed in an area upslope from the midden where an

abundance of mussel shell and debitage was seen on the surface. This test was positive for cultural

material to a depth of 60 cm. One other test, 31, was placed about 80 m to the west where possible burned

rock was seen on the surface. This test was negative and the site is not considered to extend to that point.

Looting activities appear to have severely impacted 41TV2482. Although only a little over 10 percent of

the site’s total area was directly impacted by looters, the 10 m x 10 m area of pits and back dirt piles was

the looters’ focus and was likely the most concentrated portion of the feature. The site is eligible for

formal SAL status due to impacts by looting; however, the research value of the site remains unknown.

There are no anticipated impacts to the site from park development.

41TV2483 – Explosives storage buildings (Figure 53)

There are two explosives storage buildings along an old service road that was once access to the

subdivision to the south. The one closest to Low Water Crossing Road is rectangular, 32 inches wide, 28

inches tall and 48 inches deep. It is made of formed concrete with 3 inch side walls and 4.5 inch floor and

ceiling (Figure 46). The structure faces approximately west. The door (now gone) was framed with 1.5

inch angle iron and the interior walls are lined with corrugated steel. A short 2-inch galvanized vent pipe

with rain cap is approximately centered in the roof. The structure backs into the base of the slope of the

hill to the east, about 30 meters east of the road.

The second is about 75 m to the south, and is likewise placed at the back of the hillslope, about 14 m east

of the road and also facing generally west. This structure is Quonset-shaped and is built with formed walls

and back and three precast, half-round, belled roof sections (Figure 47). These fit one into the other and

are mortared together. The rectangular base of the structure is made of 6.5-inch-thick concrete and is 50

inches wide, 5 feet tall and 9.5 feet deep. It has five 2-inch galvanized vent pipes on the back wall. Two

heavy hinge pins are present on the right side of the opening, and the door is likewise missing.

There are very few artifacts in this area, and these are limited to a few cans, except at the smaller of the

two structures where nearby are lengths of very heavy iron pipe, about 5 inches in diameter, a metal panel

from some sort of appliance, a little bit of sheet steel. The pipe may have come from the road, where a

narrow trench appears to have been cut and then backfilled.

According to a 1973 document on file at LCRA the road was discontinued, probably about 1969, and

what is now Blue Jay Lane provided access to the two structures. The smaller one is referenced as a

“dynamite cap cache” and the larger as a “dynamite cache.” There is no indication that the structures were

in use at this time, nor can it demonstrated that they were actually in place during dam construction.

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However, the document mentions the original service road, and a road is visible at that location on 1940

aerial imagery, and the structures likely date to dam construction. Although no shovel tests were

excavated, the site is considered to be fully documented and not eligible for formal SAL designation.

Figure 46. Smaller of two explosives storage buildings.

Figure 47. Larger of two explosives storage buildings.

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41TV2484–Coopers Bait Shop (Figure 54)

This twentieth century historic site is the ruins of a former fishing bait shop and store that is located on a

low terrace on the east side of Lake Austin. The northern end of the site lies just 9 m south of Low Water

Crossing Road, and northwest edge of the site is about 20 m southeast of the eastern end of the actual low

water bridge that crosses the lake. The site is situated in an area that has recently been cleared of

vegetation, principally poison ivy.

The main feature at the site consists of the western and northern sides of a foundation wall that is located

at the northwest end of the site. This feature is thought to represent the remains of the actual bait

shop/store. A small separate rubble pile of foundation material and bricks is visible on the ground about

25 m southeast of the foundation walls. The foundations and the rubble pile appear to match the locations

of two buildings that are depicted on the 1986 Mansfield Dam, Texas 7.5’ USGS map.

The north and west foundation walls of the former bait shop consist of raised limestone and cinder blocks

that indicate that the main structure measured 51.5 x 51.5 ft. in plan view. There is a 5.25 x 13.5 ft

extension near the north end of the west wall that probably represents a live bait well (Figure 48). Most of

the foundation wall on the west side of the building has a height of about 4 ft and consists of 10 horizontal

courses of limestone rock. The foundation wall at the northwest end of the building consists of cinder

blocks rather than limestone. The south and east foundation walls are not visible on ground surface and

the interior of the structure is filled with sandy sediment up to the top of the visible foundations.

Figure 48. Looking north across west wall and live well of former bait shop.

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According to the previously referenced USGS map, the second structure would have been centered about

10 m southeast of the southeast edge of the first structure. Aside from the concrete and brick rubble at this

approximate location, no other evidence of the second structure was seen. Artifacts observed on the

ground in the site area are restricted to a few broken pieces of clear glass and brown beer bottle glass.

These materials may be associated with general park usage rather than related to the bait shop.

A building may be present on an aerial map dating to 1940 at the location of the bait shop/store site. Two

or more building are definitely present on an aerial map dating to 1951 at the site location. Archival

research and oral history indicates that the business had a succession of three owners. From earliest to

these were Preston Cooper, Bob Whiteside and Ray Carter. According to an interview of local resident

Pat Kimbrough in 1995 by Carole Sikes of the Lake Travis View newspaper, the bait shop was most

commonly called Cooper’s Bait Shop and it had the first TV set in the area. Mr. Kimbrough remembered

watching Gun Smoke on the TV, and he also stated that in those days it was the only place on the lake

where a person could watch football on TV. Later, in the 1970s, the bait shop/store gained attention as a

business that was frequented by motorcycle gangs. LCRA records indicate that the bait shop went out of

business in 1981. By 1983, the building(s) had been demolished by LCRA.

In conclusion, the physical remains still present at site 41TV2484 consist of foundation walls and a rubble

pile of building materials. Few artifacts are apparent. Although no shovel tests were excavated, based on

these facts and the relatively recent age of the site, it is considered to have little further research potential

and is assessed as not eligible for formal designation as an SAL.

SUMMARY AND RECOMMENDATIONS

LCRA proposes limited improvements to its Mansfield Dam Low Water Crossing Park, located just

below Lake Travis in western Travis County. The improvements will consist of a park host site and entry

station, improved parking and a restroom. There will be no overnight facilities, and no hiking or other

trails are planned at this time. An intensive cultural resources survey was initiated when a more intensive

development plan was proposed. As a result, approximately 75 acres were surveyed or otherwise

assessed.

Previously recorded sites 41TV525 and 41TV527 were revisited and reassessed, and sites 41TV2481,

41TV2482, 41TV2483 and 41TV2484 were recorded. Sites 41TV2481, 41TV2483 and 41TV2484 are all

primarily historic component sites dating to from the early to late twentieth century. Site 41TV2481 also

has a minor prehistoric lithic scatter. These sites are all recommended as being ineligible for formal SAL

designation.

Sites 41TV525, 41TV527, and 41TV2482 all have prehistoric buried prehistoric materials that are of

unknown eligibility for formal SAL designation. However, burned rock midden site 41TV2482 has been

subjected to unauthorized excavation, and is therefore eligible for formal SAL status due to its threatened

location on LCRA lands.

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Only one site, 41TV2484 (Cooper’s Bait Shop), is located where direct impacts may occur. It is likely the

remaining foundation will eventually be removed.

LCRA cultural resources staff recommends the park development project be allowed to proceed as

described. Should future plans include development activities not described in this report then those

activities will be assessed under any antiquities permit LCRA holds at the time and/or provisions of the

Antiquities Code of Texas. Of particular interest should be the contour ridge that contains 41TV525.

Emergency discovery protocols will be in place for this project.

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Figure 49. Site 41TV525 sketch.

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Figure 55. Locations of shovel tests, red=positive, green=negative.

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REFERENCES CITED

Barnes, V. E.

1981 Geologic Atlas of Texas, Llano Sheet. Bureau of Economic Geology, The University of

Texas at Austin.

Find A Grave

2015 Hiram Hartson (1835-1920). http://www.findagrave.com/cgi-

bin/fg.cgi?page=gr&GRid=13930378. Accessed May, 2015

General Land Office

2015 Categories of Land Grants in Texas. www.glo.texas.gov/what-we-do/.../categories-of-

land-grants.pdf. accessed May 27, 2015.

Kotter, Steve

1980 An Archeological Survey of LCRA Tracts TN-1 and TN-2 (Mansfield Dam Tract), Letter

Report No. 48, Prewitt and Associates.

Malof, Andrew F., and Daniel J, Prikryl

1999 LCRA Annual Report of Investigations for 1998. Parks and Conservation Services

Department, Lower Colorado River Authority, Austin.

Parsons, Chuck

2011 Captain John R. Hughes, Lone Star Ranger. University of North Texas Press.

Texas State Library Archives Collection

2015 Reserve Militia military rolls, Reconstruction military rolls, Military rolls, Texas

Adjutant General's Department. Archives and Information Services Division, Texas State

Library and Archives Commission, Austin.

http://www.lib.utexas.edu/taro/tslac/30074/tsl-30074.html%20, Accessed April 16, 2015

Texas GenWeb

2015 Milam County, Texas. http://www.lksfriday.com/MILAM/milam-870c05.htm Accessed

April 16, 2015

U. S. GenWeb

2015 Henderson County Texas, 1850 Census.

http://www.rootsweb.ancestry.com/~txhender/Census/1850/hend1850.html Accessed

April 22, 2015.

Web Soil Survey

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2015 U.S. Department of Agriculture, NRCS Web Soil Survey.

http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx accessed 5/12/2015

Werchan, Leroy E., A. C. Lowther, and Robert N. Ramsey

1974 Soil Survey of Travis County, Texas. United States Department of Agriculture

Soil Conservation Service.

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