U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2007–1230 

Prepared in cooperation with the U.S. Department of Housing and Urban Development

CHIPS: A New Way to Monitor Colonias Along the 

United States-Mexico Border
Covers. Housing structures located in colonias within Cameron and Hidalgo Counties, August 2005 (photographs by Jean W. Parcher, 

U.S. Geological Survey).
CHIPS: A New Way to Monitor Colonias 

Along the United States-Mexico Border

By Jean W. Parcher and Delbert G. Humberson

Prepared in cooperation with the U.S. Department of Housing and Urban Development

Open-File Report 2007–1230

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2007

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Although this report is in the public domain, permission must be secured from the individual copyright owners to 

reproduce any copyrighted materials contained within this report.

Suggested citation:

Parcher, J.W., and Humberson, D.G., CHIPS: A New Way to Monitor Colonias Along the United States-Mexico 

Border: U.S. Geological Survey Open-File Report 2007–1230, 23 p.
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Acknowledgments................................................................................................................................2

History of Colonia Development..................................................................................................................3

Colonia Legislation.........................................................................................................................................3

Secretary of State Colonia Initiatives................................................................................................4

Senate Bill 827.......................................................................................................................................4

Overview of Texas State Agency Involvement with Colonias ................................................................4

The Challenge of Tracking Colonia Progress ...................................................................................4

The CHIPS Methodology ..............................................................................................................................7

CHIPS Database Development...........................................................................................................7

CHIPS as a Shared Resource .............................................................................................................8

Database Improvement and Maintenance................................................................................................9

Improving the Geospatial Boundaries of the Colonias.................................................................10

Population and Structures ................................................................................................................10

Colonia Infrastructure Priority Results.....................................................................................................13

Conclusion.....................................................................................................................................................13

References Cited..........................................................................................................................................20

Appendix A....................................................................................................................................................21

Data Dictionary for CHIPS..........................................................................................................................21

Figures

1. Map showing the location of colonias in Texas with 100 miles of the United 

States-Mexico border, 2003 ........................................................................................................2

2. The demographic, infrastructure, and health criteria collected for each colonia as

determined by the Senate Bill 827 Workgroup ........................................................................5

3–5. Screen shots showing—

3. The database schema for the Colonia Health, Infrastructure, and Platting Status 

Tool .........................................................................................................................................8

4. The graphic user interface used to enter colonia data ................................................9

5. The custom report generator...........................................................................................10

6. Map showing an updated colonia boundary compared to its previous boundary in 

El Paso County.............................................................................................................................11

7. Graph showing the distribution of green, yellow, and red colonias within the six 

counties contained in the Colonia Health, Infrastructure, and Platting Status tool 

(CHIPS) .........................................................................................................................................12

8–13. Maps showing—

8. The distribution of green, yellow, and red colonias within Cameron County...................14

9. The distribution of green, yellow, and red colonias within El Paso County......................15

10. The distribution of green, yellow, and red colonias within Hidalgo County .....................16

11. The distribution of green, yellow, and red colonias within Maverick County ..................17

12. The distribution of green, yellow, and red colonias within Starr County ..........................18

13. The distribution of green, yellow, and red colonias within Webb County.........................19
iv

Tables

1. Colonia identification numbers...................................................................................................4

2. Classification criteria for colonias.............................................................................................6

3. Summary of Texas Legislative Grant and Loan Programs .....................................................6

4. Summary of Texas regulation and support agencies .............................................................6

Conversion Factors

Multiply By To obtain

Length

mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2

)

acre 0.4047 hectare (ha)

acre 0.4047 square hectometer (hm2

) 

acre 0.004047 square kilometer (km2

)
Abstract

Colonias, which are unincorporated border settlements in 

the United States, have emerged in rural areas without the governance and services normally provided by local government. 

Colonia residents live in poverty and lack adequate health 

care, potable water, and sanitation systems. These conditions 

create substantial health risks for colonias and surrounding communities. By 2001, more than 1,400 colonias were 

identified in Texas. Cooperation with the U.S. Department of 

Housing and Urban Development, Offices of the Texas Attorney General, Secretary of State, and the Texas Water Development Board has allowed the U.S. Geological Survey (USGS) 

to improve colonia Geographic Information System (GIS) 

boundaries and develop the Colonia Health, Infrastructure, 

and Platting Status tool (CHIPS). Together, the GIS boundaries and CHIPS aid the Texas government in prioritizing the 

limited funds that are available for infrastructure improvement. 

CHIPS’s report generator can be tailored to the needs of the 

user, providing either broad or specific output. For example, a 

congressman could use CHIPS to list colonias with wastewater 

issues in a specific county, whereas a health researcher could 

list all colonias without clinical access. To help cities along the 

United States-Mexico border manage issues related to colonias 

growth, CHIPS will become publicly available in an Internetenabled GIS as part of a cooperative study between the USGS, 

the U.S. Department of Housing and Urban Development, 

and the Mexican Instituto Nacional de Estadística Geografía e 

Informática.

Introduction

The Handbook of Texas Online (<http://www.tsha.utexas.

edu/handbook/online/>) defines colonias as unincorporated 

and unregulated settlements which emerged during the 1960s 

along the United States-Mexico border (Texas State Historical 

Association, 2003). Most colonias are located in Texas (more 

than 1,400 in 2001, fig. 1), but there are 80 in Arizona and 120 

in New Mexico (Ward, 1999; Norman and others, 2006). The 

emergence of colonias within the U.S.-Mexico border region 

can be traced to the rapid growth associated with the Mexican Border Industrial Program during the 1960’s. Increased 

economic growth on the Mexican side of the border fueled 

population expansion in the sister cities (Parcher, 2002). These 

transfrontier “sister” or “twin” cities are communities where 

a city in one country borders a city in another, creating a 

large urban area separated by administrative boundaries. This 

rapid population growth created a lack of affordable housing, 

causing new migrants in the United States to purchase rural 

homestead lots through a contract for deed program from land 

developers. Because of the need to keep prices affordable and 

the absence of effective land-use controls, these homesteads 

expanded into rural subdivisions without proper infrastructure 

(Davies and Holz, 1992). These substandard unincorporated 

subdivisions are commonly called colonias. Since the region 

is binationally interconnected economically, politically, and 

socially, the phenomenon of colonias in the United States is a 

transborder issue.

Population growth along the United States-Mexico border 

followed the world trend from a rural to a more urban environment (14 percent urban in 1900, almost 50 percent urban in 

1990);(Douglas, 1994), with most of the population growth 

occurring in the major transfrontier cities. This uneven distribution of population growth left vast tracts of deserts, rangelands, and mountain regions with limited population (Forster 

and Cleveland, 2005). Demographic change within the border 

region is driven by United States and Mexican economic 

forces which are affected by global trends (Peach and Williams, 2003). Similar trends in United States and Mexican border demographics include greater than world average annual 

rates of growth (U.S. Census Bureau, 2006) during the 1990’s 

(5 percent average annual growth for the Chihuahua, Coahuila 

and Baja California border region, 4 percent average annual 

growth for the Texas border region) characterized by young 

Hispanic migrants (Peach and Williams, 2003). This population growth, fueled by a source of inexpensive labor desiring 

home ownership (Davies, 1992), created peri-urban (land area 

on the fringe of a city) expansion in barren areas outside of 

municipal boundaries. Land developers profited from subdividing marginal rural areas without providing basic infrastructure services. The lack of county enforcement of proper land 

administration procedures allowed for the expansion of these 

CHIPS: A New Way to Monitor Colonias Along the United 

States-Mexico Border

By Jean W. Parcher and Delbert G. Humberson
2 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

subdivided rural areas into colonias, which were affordable 

because of their rural location, but too costly for municipalities 

to provide infrastructure services. 

Formalized land administration systems are critical 

components for societies to increase their market economies, 

plan for sustainable development, and reduce land conflict 

issues (Enemark, 2004; Deininger, 2004). The process of 

implementing land administration systems includes official 

recording of land tenure, land value, land use, and land development for each parcel (Van der Molen, 2004). Efficient and 

legal land administration systems aid in reducing land conflicts for societal groups that traditionally are discriminated 

against, and provide an efficient structure for delivering basic 

public services (Deininger, 2004). Many factors contributed 

to a breakdown of the land administration system during the 

1970s and 1980s along the United States-Mexico border, 

which resulted in the explosion of colonias. These factors 

included: a lack of affordable housing opportunities, a largely 

migrant population without access to real-estate credit, differences in cultural practices, and insufficient county enforcement resources (Ward, 1999; Henneberger, 2000; Carter and 

Ortolano, 2004). Developers kept land prices affordable by 

restricting public infrastructure development; affordable pricing ensured a demand for colonia homesteads, even though 

the developers maintained the original title of the land until 

the contract for deed was paid in full (Ward, 1999; Carter 

and Ortolano, 2004). Therefore, in one of the richest countries in the world, the formalized land administration system 

was bypassed, which resulted in discrimination against the 

Hispanic migrant population, located in the poorest counties 

of the United States. 

 The unsanitary living conditions created by the lack of 

infrastructure in the colonias initiated a political movement 

by United States-Mexico border residents in the late 1980s. 

The goal of the movement was to lobby the Texas Legislature 

to support public funding for infrastructure improvements to 

alleviate third world settlements in the United States (Carter 

and Ortolano, 2004). 

Acknowledgments

The authors would like to acknowledge the support of the 

Office of the Texas Secretary of State, Office of the Attorney 

General of Texas, and the Texas Water Development Board. 

Also, special recognition is deserved by the Office of the 

Texas Secretary of State colonia ombudsmen, who dedicated 

their time to collect the infrastructure data needed for the 

Figure 1. The location of colonias in Texas with 100 miles of the United States-Mexico border, 2003.
Colonia Legislation 3

Texas Legislature report. Without the efforts of the aforementioned, this report would not have been possible.

History of Colonia Development 

The key elements for colonia development included the 

need for affordable housing and the lack of county enforcement of land administration procedures (Ward, 1999). Since 

these makeshift settlements materialized on marginal agricultural land located far from incorporated cities, developers were 

able to lure low-income families to purchase a lot through a 

contract for deed. This allowed the residents to purchase the 

land with little or no down payment and to construct the permanent housing unit as funds became available (Ward, 1999; 

Carter and Ortolano, 2004). The contract for deed ensured 

that the land title remained with the developer until the loan 

had been paid in full; therefore foreclosure resulted in the land 

developer repossessing the land. Since settlements had been 

established outside the formally sanctioned governance of 

nearby cities and towns, county enforcement resources were 

insufficient to enforce the verbal agreements of the developer 

to follow through with public utility infrastructure needs. 

Texas colonia demographics consist of a majority of lowincome residents of Hispanic origin, with at least 65 percent 

holding United States citizenship (Ward, 1999; Salinas and 

others, 1988). Most are located outside of municipal boundaries in rural areas; therefore colonia residents traditionally have 

struggled to gain access to basic infrastructure services such as 

water and sanitary systems. 

Lacking public infrastructure and suffering from extreme 

poverty, many colonia residents relied on unsanitary sources 

for water and wastewater disposal. Rapid population growth 

in the border region during the 1980s resulted in a population density too high to be supported by inadequate sanitary 

systems such as cesspools and septic systems. Medical professionals observed a rise in health issues such as dysentery, 

hepatitis, and tuberculosis among the colonia residents. The 

poverty, poor health, and lack of sanitation in the colonias 

became national issues during the public debates discussed 

during the passage of the North American Free Trade Agreement (NAFTA). Political pressure from local residents and 

non-governmental organizations (NGOs) to improve the living 

conditions of colonia residents resulted in the Texas state government taking action (Carter and Ortolano, 2004). 

Colonia Legislation

In 1989 state and federal laws were passed to limit the 

expansion of colonias, and to provide funding to address their 

infrastructure needs. This legislation addressed various legal 

and infrastructure issues, but did not alleviate the problem 

of lack of affordable housing. The 71st Texas Legislature 

passed Senate Bill 2 in 1989 to restrict future development of 

colonias in Texas (Ward, 1999; Carter and Ortolano, 2004). 

Senate Bill 2 established the Economically Distressed Area 

Program (EDAP), which is administered by the Texas Water 

Development Board (TWDB). EDAP assistance grants can 

be obtained for communities with inadequate water or sewer 

systems located in counties with 25 percent unemployment 

and a per capita income 25 percent below state average. These 

grants provided the incentives for municipalities and utility 

companies to provide water and sewer systems to the colonias, 

many of which were located far from urbanized areas. Senate 

Bill 2 also enforced Model Subdivision Rules (MSR), which 

had to be adopted and enforced to receive EDAP funding. The 

MSR require that new subdivisions of land subdivided into 

tracts of 5 acres or less must provide adequate water and sewer 

infrastructure. MSR regulations apply to all subdivisions created after county adoption of the rules.

Another major reform was the Colonia Fair Land Sales 

Act that was passed as Senate Bill 336 during the 74th Texas 

Legislature Session, 1995 (Ward, 1999; Carter and Ortolano, 

2004). Senate Bill 336 restricts the recession and foreclosure 

clauses and requires disclosure and bi-lingual availability of 

transactional documents for all contracts for deed legal affairs. 

Senate Bill 336 also allowed for converting the contract for 

deed to a mortgage when 40 percent of the purchase price, or 

48 monthly installments, have been paid. This greatly reduced 

the number of foreclosures. 

Even though the 10th Amendment to the Constitution in 

the United States empowers local governments to preside over 

land-use decisions, legislation was passed at the federal level 

to provide financial resources to alleviate extreme poverty in 

the colonias along the international border. In 1990 the U.S. 

Congress passed the Cranston-Gonzalez Affordable Housing Act, which stipulated that 10 percent of all Housing and 

Urban Development Community Development Block Grants 

be awarded to colonias project developments in the United 

States-Mexico Border states. The funding was passed to state 

government for distribution to local entities to improve colonia 

infrastructure and quality of life conditions. Even with proper 

legislation and financial assistance grants, the definition of a 

colonia was never agreed upon in Texas or within the United 

States. Each federal or state agency providing funding to a 

colonias initiative maintains their own definition of a colonia. 

This inconsistency is shown on the Office of the Texas Secretary of State colonias Web site: http://www.sos.state.tx.us/

border/colonias/what_colonia.shtml. 

All definitions agree that colonias lack adequate water 

and sewer systems, but disagree on the geographic location 

of the colonias (within 150 miles of the border or in a county 

with per capita income 25 percent below state average) or on 

the size of a colonia (five or more housing units or population less than 10,000). On another issue, if a colonia receives 

sufficient infrastructure development, proper access to health 

care and education opportunities, and becomes incorporated 

into county or city governance, does it become a subdivision 

instead of a colonia? In other words, when is a colonia no 

longer a colonia?
4 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Secretary of State Colonia Initiatives

In 1999, Texas legislators passed Senate Bill 1421 in an 

effort to manage colonia infrastructure priorities for water 

and wastewater services. As a result, positions were created 

for a Director of Colonia Initiatives and six ombudsmen to 

serve under the Office of the Texas Secretary of State. The 

ombudsmen work in the six Texas counties with the highest 

colonia populations: Hidalgo, El Paso, Starr, Webb, Cameron 

and Maverick (Office of the Texas Secretary of State, 2006). 

Working with colonia residents, federal and state agencies, 

local governments, non-profit organizations, and utility 

companies, the ombudsmen coordinate meetings, monitor 

the status of water/wastewater projects, collect household 

information, and aid in the collection and review of required 

documents for agencies funding an infrastructure project. In 

addition to this, ombudsmen organize collaborative initiatives 

to provide needed services to colonia residents, such as medical and dental services (Office of the Texas Secretary of State, 

2006). 

Senate Bill 827 

With the passing of Senate Bill 827 by the 79th Texas 

Legislature in 2005, the state was mandated to create a colonia 

identification system, and track the progress of state funded 

colonia improvement projects. These efforts were spearheaded 

by the Office of the Texas Secretary of State, and the Senate 

Bill 827 workgroup was formed. This workgroup consists of 

the Department of State Health Services, Health and Human 

Services Commission, Office of the Attorney General of 

Texas, Office of Rural Community Affairs, Texas Commission on Environmental Quality, Texas Department of Housing 

and Community Affairs, Texas Department of Transportation, 

Texas Water Development Board, and the Office of the Texas 

Secretary of State (Office of the Texas Secretary of State, 

2006). To create a colonia identification system, the Office of 

the Texas Secretary of State adopted an existing identification system from the TWDB. With this system, each colonia 

is identified by a unique eight digit code beginning with the 

letter “M” followed by a seven digit numerical value. The first 

three numerical digits are the Texas county number for the 

colonia’s county; the last four digits are numbers assigned in 

sequential order to the colonias (table 1).

To track the progress of state funded projects, the Senate 

Bill 827 workgroup created a set of infrastructure, demographic, and health-related criteria for the ombudsmen to 

collect in the six counties. These criteria were grouped into 

five sections (fig. 2), and aided in classifying colonias by the 

degree of health hazard that they pose, as well as track the 

overall progress of state-funded projects that have benefited 

colonias within 62 miles of the border. The ombudsmen collected data from a variety of sources, including site visits, 

utility companies, county appraisal districts, and the Office of 

the Attorney General of Texas.

Table 1. Colonia identification numbers.

County name 

(Texas county 

number ) Possible colonia identification numbers

Cameron (031) {M0310001, M0310002, M0310003,..., M0319999}

El Paso (071) {M0710001, M0710002, M0710003,..., M0719999}

Hidalgo (108) {M1080001, M1080002, M1080003,..., M1089999}

Maverick (162) {M1620001, M1620002, M1620003,..., M1629999}

Starr (214) {M2140001, M2140002, M2140003,..., M2149999}

Webb (240) {M2400001, M2400002, M2400003,..., M2409999}

Once the classification information was collected by the 

ombudsmen, colonias were to be classified based on health 

risk. This classification was interpreted by the Senate Bill 827 

workgroup to mean a classification based on the status of their 

infrastructure (table 2). 

Overview of Texas State Agency 

Involvement with Colonias

With the inception of the 1989 EDAP financial assistance 

legislation authorizing the TWDB to provide grants for water 

and wastewater projects, various other state agencies in Texas 

have become involved in colonias initiatives. To monitor the 

effectiveness of the programs, Senate Bill 827 requires the 

Office of the Texas Secretary of State to submit a report every 

2 years to the legislature. The first report was submitted in 

December 2006. To develop the report and tracking system, 

the Senate Bill 827 workgroup and other invited agencies such 

as the USGS and the Center for Housing and Urban Development (CHUD) of the College of Architecture at Texas A&M 

University met regularly on a monthly basis during 2006. The 

final report can be accessed at: http://www.sos.state.tx.us/

border/colonias/reports.shtml.

Section 4.0 of the Senate Bill 827 report provides detailed 

information concerning state agency legislative grant and loan 

programs for colonias (table 3). 

In addition to financial support, various state agencies 

provide economic and community development assistance 

(table 4). For example, CHUD maintains three regional offices 

and 19 community resource centers along the border. These 

community resource centers provide social infrastructure services such as education, work force development, health and 

human services, and programs for youth, women, and elderly 

to enhance the ability of colonia residents to become self sufficient (Center for Housing and Urban Development, 2006). 

The Challenge of Tracking Colonia Progress

The first comprehensive colonias database compilation 

for Texas was undertaken by the TWDB in 1992. Their
Overview of Texas State Agency Involvement with Colonias 5

 1) Identification

County_________________________

Colonia ID # __________________

Colonia Name (s)________________

Est. Colonia Population ___________

 2) Platting

*If not in the TWDB/OAG Database, has the colonia been platted? (Y/N/Unknown)

If yes, has the plat been recorded? (Y/N/Unknown)

If yes, please provide the date it was recorded. ______________

If no, does a map exist? (Y/N/Unknown)

If no, when was the community first established? ______________

 3) Infrastructure

Water

*How is potable water provided in this colonia?

_____ Public water distribution system (Y/N/Partial)

_____ Private wells? (Y/N/Partial)

_____ Hauled in? (Y/N/Partial)

*Do all lots have a potable water supply? (Y/N)

Wastewater

*Is a wastewater collection system available in the colonia? (Y/N/Partial)

*Are there lots not served by adequate wastewater disposal? (Y/N/Partial)

Solid Waste Disposal

*Is a trash collection system available in the colonia? (Y/N/Partial)

Drainage

*Does the colonia flood during rainfall? (Y/N/Partial)

*Is any part of the colonia in a flood plain? (Y/N/Partial)

Roads

*Are the streets and roads passable in all weather conditions? (Y/N/)

*Are access roads from the colonia to public roads paved? (Y/N/Partial)

 4) Access to, and Information about, Health

*Is it a health professional shortage area? (Y/N)

*Is there access to a Texas A&M Community Resource Center, a clinic, mobile clinic or transportation

to a clinic available? (Y/N)

*Are promotoras or a comparable outreach program available in the area? (Y/N/Partial)

 5) Financial Availability

*List the federal and/or state agencies, non-profit organizations and other entities that are currently servicing the 

colonia and the type of project/service they are/will be providing.

Name of Agency Type of Project Service to be/being provided

1.________________________________________________________________

2.________________________________________________________________

3.________________________________________________________________

Figure 2. The demographic, infrastructure, and health criteria collected for each colonia as determined by the Senate Bill 

827 Workgroup.
6 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Table 2. Classification criteria for colonias.

Degree of health risk Classification level Criteria

High health risk Red Satisfies at least one of the following: 

1. Either all or some lots have inadequate wastewater disposal (cesspools).

2. All lots do not have a potable water supply.

3. Not platted.

Medium health risk Yellow Platted colonias with a potable water supply and adequate wastewater disposal, and 

satisfy at least one of the following:

1. Either all or some lots lack solid waste disposal (trash collection).

2. Not all roads are paved.

3. Not all roads are passable in all weather conditions.

4. It floods during a precipitation event.

Low health risk Green All lots satisfy all of the following criteria:

1. Platted.

2. Have a potable water supply.

3. Have adequate wastewater disposal.

4. Have solid waste disposal.

5. All roads are paved.

6. All roads are passable in all weather conditions.

7. It doesn’t flood during a precipitation event.

Table 3. Summary of Texas Legislative Grant and Loan Programs.

Agency Program Federal cooperators Date began Services

Texas Water Development 

Board

EDAP NadBank, Environment Cooperation 

Commission, Environmental Protection Agency, U.S. Department 

of Agriculture 

1989 Water and wastewater 

grants

Office of Rural and Community AffairsCommunity Block Grants Housing and Urban Development 2002 Infrastructure

Texas Department of 

Transportation

General Obligation Bonds Federal Highways 2002 Road paving and drainage

Department of State 

Health Services

Office of Border Health Center for Disease Control, The 

Rensselaerville Institute

1993 Public Health

Texas Department of 

Housing and Community Services

Texas Bootstrap Program Housing and Urban Development Not available Mortgage assistance, 

home repairs

Table 4. Summary of Texas regulation and support agencies.

Agency Support services

Office of the Texas Secretary of State Ombudsmen program

Office of the Attorney General of Texas Enforcement of legislation, cartography

Health and Human Services Human health services

Texas Commission of Environmental Quality Certificates of convenience and necessity, Regulation of onsite sewerage, water 

quality, and model subdivision rules

Texas A&M Center for Housing and Urban Development Community resource centers
The CHIPS Methodology 7

goal was to identify eligible areas for water and wastewater 

infrastructure assistance under the EDAP. In the 37 border 

counties located within 100 kilometers of the border, the 

TWDB identified 1,193 colonias with an estimated population of 279,863 (Office of the Texas Secretary of State, 

2006). This comprehensive report provided a baseline of 

water and wastewater infrastructure needs for state and 

federal policy makers to identify the scope of the problem. 

Further updates were made to the database in 1995 and 1996 

by the TWDB. 

To provide a geographic context, the Office of the 

Attorney General of Texas produced an extensive colonias 

geographic database with online maps at http://maps.oag.

state.tx.us/colgeog/. This geographic database used original 

plat maps and digital transportation files to georeference 

the location of the colonia boundaries. The TWDB comprehensive database was integrated into the Office of the 

Attorney General of Texas’s geographic database by using 

similar unique colonia identifiers. The Office of the Attorney General of Texas worked with the U.S. Census Bureau 

in 2000 to include colonia areas in the census enumeration 

programs.

In 2003, the TWDB performed a revision of water 

and wastewater needs for colonias located in their EDAP 

designated counties. Procedures used to revise the database 

included contacting county local officials for infrastructure 

needs, integrating data from the county comprehensive data 

studies (produced through grants obtained from the Office 

of Rural Community Affairs), and contractor site visits. This 

revision identified 2,333 distressed areas with an estimated 

population of 484,892. Of these distressed areas, 1,409 were 

identified, with an estimated population of 212,709 having 

inadequate water or substandard wastewater processes/treatments. 

In 2003, the USGS began a study in cooperation with 

the U.S. Department of Housing and Urban Development 

(HUD) to build binational geospatial databases for select 

sister city areas along the United States-Mexico border. The 

project integrated the colonias geographic and infrastructure 

data into a regional context to provide city planners with the 

necessary information to estimate funding needs from federal agencies. In recognizing that Mexican border cities play 

an important economic role for the United States border cities, the binational aspect of the project provided information 

for regional planning. The USGS incorporated the TWDB 

and Office of the Attorney General of Texas databases into 

their project, and partnered with local government to share 

utility, transportation, and appraisal district data. These 

partnerships provided the mechanism to maintain local data 

and to improve the geographical boundaries for the colonias. 

The EDAP database provided an excellent foundation 

for monitoring colonia development. Yet the different criteria collected to classify health risk level in the colonias for 

Senate Bill 827 required the development of a new database 

to store and analyze the current (2006) colonias data. Based 

on requirements outlined in Senate Bill 827, and in cooperation with the Office of the Texas Secretary of State, the USGS 

developed The Colonia Health, Infrastructure, and Platting 

Status tool (CHIPS) database of colonia conditions, using 

local government data initiatives and local ombudsmen information. 

The CHIPS Methodology

Since colonias are not uniquely represented within the 

census geography, an explicit long term working database 

is needed to monitor progress, set infrastructure priorities, 

and measure quality of life indicators within the colonias. 

CHIPS uses a relational database to house the colonias data, 

which provides many benefits. For example, gathering data 

tables from multiple sources does not require manipulation 

of the datasets to force them into one table; instead, new 

tables remain their own separate entity. In addition to making data more manageable, this also helps prevent duplication 

of information because of repeated copying and pasting. The 

relational database also allows the use of Structured Query 

Language (SQL). Using SQL, users can manipulate how data 

are displayed without altering the original data tables. Another 

benefit is the database’s open ended design, which facilitates 

the addition of data from other sources. 

CHIPS Database Development

The classification criteria created by the Senate Bill 827 

workgroup served as a template for the CHIPS’s database 

schema. Essentially, the five classification categories were 

translated into five separate tables. For each table, a field was 

specified for each individual criterion and the tables were 

linked together by the unique identification numbers (fig. 3). 

Note that the five tables and their fields correspond with the 

criteria outlined by the Senate Bill 827 workgroup.

Under this schema, data entry rules and drop-down 

menus were created to facilitate data entry within a graphical user interface, which allows rapid data entry regardless 

of the user’s level of familiarity with database structure (fig. 

4). Using dropdown boxes ensures that all data are entered 

consistently, which allows for rapid querying. The top part 

of the graphical user interface contains the identification 

information and is always visible. The tabs labeled “Platting”, 

“Infrastructure”, “Health Care”, “Financial Availability”, 

and “Create Report” allow the user to choose the category to 

manipulate. 

Because Senate Bill 827 requires a biennial report to be 

submitted by December 1st on even years, it is imperative 

that the data are stored in a format that is easily updatable and 

capable of generating custom reports rapidly. To accommodate 

this, two other functions were added to CHIPS. The first function provides CHIPS with the capability of updating the color 

classification of every colonia with a click of a single button. 
8 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

This automated process eliminates any human error associated 

with attempting to manually classify thousands of colonias. 

This procedure is designed to be altered easily if the classification criteria change.

The second function is a custom report generator that is 

integrated into the graphical user interface. This allows users 

with little or no knowledge of SQL or database queries to 

extract information with ease. The report generator is flexible, 

and its output can be tailored to be either broad or specific. 

For example, a congressman could use CHIPS to list colonias 

with wastewater issues in a specific county, while a health 

researcher could list all colonias without clinical access (fig. 

5).

Although CHIPS does not currently (2006) maintain 

a database of funds spent for infrastructure development, 

it has been designed to readily accept a financial data table 

with links to each colonia. This information could be entered 

and displayed by clicking on the fourth tab in the upper left 

corner labeled “Financial Ability”. This is the next step in the 

database’s development, and is being explored by the Office 

of the Attorney General of Texas and the Office of the Texas 

Secretary of State. Finally, although CHIPS is a powerful tool, 

it would have been impossible without the dedication and hard 

work of the Colonia Ombudsmen.

CHIPS as a Shared Resource

The USGS provided technical support by developing 

CHIPS’s database and report generator for the Senate Bill 827 

Colonias Initiative report. The Office of the Texas Secretary 

of State’s Colonia Initiative populated CHIPS with data, and 

incorporated the results into the Senate Bill 827 Colonias 

Initiative report for the Texas Legislature. As of February 

2007, CHIPS is under the auspices of the Office of the Texas 

Secretary of State. The Office of the Attorney General of 

Figure 3. The database schema for the Colonia Health, Infrastructure, and Platting Status Tool.
Database Improvement and Maintenance 9

Texas plans to incorporate the infrastructure information with 

their Colonias geographic database. The version of CHIPS 

used for the Senate Bill 827 Colonias Initiative report can be 

downloaded from http://borderhealth.cr.usgs.gov/datalayers.

html.

In 2007, the 80th Texas Legislature passed Senate Bill 99, 

which mandates state agencies to report the status of water, 

wastewater, and other infrastructure projects in colonias to the 

Office of the Texas Secretary of State, and requires an updated 

report to the Texas legislature concerning the progress of statefunded colonia projects every even number of years (Texas 

Legislature Online, 2007). CHIPS could serve as the database 

for storing the new infrastructure project information, and for 

generating reports. 

Database Improvement and 

Maintenance 

The dynamic nature of colonias requires a strategy 

for maintaining current information. Data collected at the 

county level should provide the most up-to-date source. The 

challenge is to incorporate current county level data in the 

maintenance and improvement of CHIPS, thereby alleviating 

the need for large sums of funding to update the database. 

The use of the M number (table 1) as a standard colonia 

identification system within Texas allows other agencies to 

collect specific information, such as health statistics, and link 

it to CHIPS. 

Figure 4. The graphic user interface used to enter colonia data.
10 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Improving the Geospatial Boundaries of the 

Colonias

In addition to CHIPS, accurate colonia boundaries are 

needed to monitor demographic changes, housing densities, 

and to serve as spatial references to existing infrastructure 

development. When the original GIS boundaries were created 

by the Office of the Attorney General of Texas, plat maps were 

used to get colonia outlines, which were georeferenced with 

electronic Emergency Medical Services maps. However, with 

the availability of more precise 2004 Digital Ortho Quarter 

Quad (DOQQ) imagery from the National Agriculture Imagery Program (NAIP), inaccuracies in the colonia locations 

were revealed. Working closely with the Office of the Attorney 

General of Texas, Maverick County Appraisal District, and El 

Paso County Appraisal District, the USGS updated the colonia boundaries in Maverick and El Paso counties. This was 

accomplished by using a combination of 2004 NAIP imagery 

and local appraisal district plat data (fig. 6).

Population and Structures

Accurately assessing demographic information for 

colonias is difficult. Because of confidentiality issues, colonia 

boundaries are not used for census enumeration units. Migrant 

employment creates absentee ownership and a mobile population. Various methods have been used to estimate population 

statistics for colonias. These include using aerial photos and 

remote sensing interpretation to count occupied structures and 

apply an average population estimate for each dwelling (Holz 

and Davies, 1992), door to door surveys (Ward, 1999), or a 

statistical allocation of 2000 census data based on proximity 

to transportation routes (Xiong, 2005). One of the limitations 

that exist for each method is the difficulty to track changes 

each year. The USGS piloted the use of digital county appraisal 

district data to estimate the number of occupied lots, which 

was suggested by the Maverick County Appraisal District (P. 

Medellin, oral commun., 2005). Appraisal district data are used 

to generate tax revenue; therefore, even economically disadvantaged counties invest in automated digital practices and maintain an up-to-date database. The USGS received a database 

listing of subdivisions in Maverick county with all platted lots, 

including information on whether or not an improvement exists 

on the lot. Matching the received subdivision names with a list 

of colonia names provided a method by which to count the total 

lots in each colonia and the number of improved lots in each 

colonia. Although this is not an explicit count of the number 

occupied lots, these data enabled us to derive an estimate by 

assuming that an improved lot is an occupied lot. To estimate 

Figure 5. The custom report generator.
Database Improvement and Maintenance 11

Figure 6. An updated colonia boundary compared to its previous boundary in El Paso County.
12 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Figure 7. The distribution of green, yellow, and red colonias within the six counties contained in the Colonia Health, Infrastructure, and 

Platting Status tool (CHIPS).
Conclusion 13

population, calculate the average population for each household 

and apply it to the number of improved lots.

Colonia Infrastructure Priority Results

The color classification of the colonias is fully automated by CHIPS. CHIPS calculates which colonias are red 

(high health risk), yellow (medium health risk) and green 

(low health risk) by using the health and infrastructure criteria 

provided by the Senate Bill 827 workgroup. The results of 

this classification display the distribution of the colors among 

the counties included in CHIPS, which are Cameron, El Paso, 

Hidalgo, Maverick, Starr, and Webb counties (fig. 7). Of the 

1,786 colonias identified in CHIPS, 36 percent are identified 

as green, which is higher than the percentage of colonias identified as red (24.2 percent) or yellow (22.5 percent), but still 

less than the combined percentage of red and yellow colonias 

(46.7 percent). The report generator of CHIPS allows a quick 

comparison of the distribution of colonias between counties. 

For example, 10 percent of the colonias are located in Cameron county, but Cameron county has 14.5 percent of the green 

colonias; conversely, Maverick county has 4.1 percent of the 

colonias, but only 2.3 percent of the green colonias. 

The results generated by CHIPS indicate where funds 

for colonia projects are most needed (fig. 8). Hidalgo County 

accounts for 84.5 percent of the unknown colonias in the 

six counties. This percentage represents 261 colonias where 

funding should be spent to collect current infrastructure data 

to properly classify the colonias. Once they are classified, a 

more meaningful distribution can be created and used to direct 

future funding.

Individual county maps depict the distribution of green, yellow, and red colonias within them (fig. 9–13). These maps show 

the trends within a single county rather than between different 

counties. With the exception of Cameron County, red colonias 

tend to be located away from major urban areas and transportation routes. This is not surprising since many red colonias are 

not connected to city water mains because of heavy construction 

costs; however, several red colonias are intermingled with green 

ones in Cameron County. These warrant extra investigation since 

the costs involved with connecting them to adequate water and 

wastewater lines would be relatively minimal.

In addition to the spatial distribution of the colonias, the 

maps also display the numerical distribution of the green, yellow, and red colonias. Cameron and El Paso counties have most 

of their colonias classified as green (52 percent and 55 percent, 

respectively), which reflects the progress that has been made 

in those counties as far as infrastructure improvement; however, more than 40 percent of the colonias in Cameron and El 

Paso counties still need improvement. Hidalgo County is more 

evenly distributed with 29 percent green, 29 percent yellow, 

and 15 percent red; but it is too early to estimate for Hidalgo 

County since 28 percent of the colonias remain classified as 

unknown. Maverick, Starr, and Webb counties have more 

colonias classified as red than any other color (43 percent, 44 

percent, and 92 percent, respectively). Of the six counties in 

CHIPS, Maverick and Webb counties have the lowest number 

of colonias. If the state of Texas previously invested in projects 

for areas of large colonia density, these low numbers could 

explain the high ratio of red to green colonias. Should this be 

the case, CHIPS can help policy makers determine when to 

invest in these lesser populated areas as well.

Conclusion 

As shown by Texas legislation, there is a need to track 

infrastructure, health, and quality of life indicators for colonia 

residents. This tracking system needs to measure performance 

of financial expenditures against actual improvements, and 

provide a method to determine future priorities. CHIPS can 

provide information to support infrastructure priorities. The 

output reports provide the information needed for planning and 

funding purposes. The maps and graphs created from CHIPS’s 

database provide an intuitive manner to compare the distribution of red, yellow, and green colonias between counties, as 

well as within counties. The current (2006) results display the 

critical need to provide resources to identify the infrastructure 

status for the unknown colonias in Hidalgo County.

CHIPS’s graphical user interface provides an easy 

method to analyze the data and update the information, even 

for those with limited database experience. The color classification process is fully automated, thus preventing human 

errors. The statewide colonias identification system provides 

a method to link other state agency databases to each individual colonia. Therefore, other agencies can maintain their 

own working database and link the information to CHIPS as 

needed for reporting purposes. For example, the Texas Department of Health Services can maintain disease statistics for a 

county with a summary of cases linked to the colonia identification system. Each agency in the Senate Bill 827 workgroup 

can track colonia financial expenditures in their agency database using the colonia identification system. Therefore, for 

the next biannual legislation, the financial expenditures could 

be generated easily for each colonia. To improve cooperation 

and reduce duplication, it is recommended that a single state 

agency be designated as the steward of the database. 

Improvement to CHIPS could include better defined criteria for subjective information, such as road conditions during 

a flood. Also, inconsistencies exist between earlier databases 

and the information in CHIPS. Thus, ongoing quality-assessment and quality-control processes need to be continued to 

ensure the integrity of the database. As the data are revised, 

historical reports should be maintained for analyzing colonia 

improvement or deterioration. 

Since the underlying issue for colonias is a lack of 

affordable housing, ongoing legislation may not have sufficiently addressed this problem. For example, with the 

conversion of the contract for deed into land title, and less 
14 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Figure 8. The distribution of green, yellow, and red colonias within Cameron County.
Conclusion 15Figure 9. The distribution of green, yellow, and red colonias within El Paso County.
16 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Figure 10. The distribution of green, yellow, and red colonias within Hidalgo County.
Conclusion 17

Figure 11. The distribution of green, yellow, and red colonias within Maverick County.
18 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

Figure 12. The distribution of green, yellow, and red colonias within Starr County.
Conclusion 19Figure 13. The distribution of green, yellow, and red colonias within Webb County.
20 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

opportunities for new settlements because of the Model Subdivision Rule, colonia residents began to subdivide each colonia 

into smaller plats of land, many times occupied by related 

family members. With proper water and sanitation services, 

this would not result in overcrowding, but with cesspools and 

septic systems, a health hazard has resulted. This illustrates the 

need to closely monitor colonia infrastructure with a flexible 

tool capable of recording infrastructure changes and rapidly 

generating reports to monitor progress, which is a role wellsuited for CHIPS. 

References Cited

Carter, N., and Ortolano, L., 2004, Implementing government 

assistance programs for water and sewer systems in Texas 

colonias: International Journal of Water Resources Development, v. 20, no. 4, p. 553–564.

Center for Housing and Urban Development, College of 

Architecture, Texas A&M University, accessed July 7, 2007, 

at http://archone.tamu.edu/chud/Overview.html

Davies, C.S., and Holz, R.K., 1992, Settlement evolution of 

“colonias” along the US-Mexico border, the case of the 

Lower Rio Grande Valley of Texas: Habitat International, 

v. 16, no. 4, p. 119–142. 

Deininger, K.W., 2004, Land policies for growth and poverty 

reduction: Key issues and challenges ahead: Inter-regional 

Special Forum on the Building of Land Information Policies 

in the Americas: Aguascalientes, Mexico, October 26–27, 

2004: accessed July 6, 2007, at http://www.fig.net/pub/

mexico/papers_eng/ts2_deininger_eng.pdf

Douglas, Ian, 1994, Human settlements: In Changes in Land 

Use and Land Cover: A Global Perspective: Press Syndicate 

of the University of Cambridge, p. 149–170.

Enemark, Stig, 2004, Building land information policies: 

Inter-regional Special Forum on the Building of Land Information Policies in the Americas: Aguascalientes, Mexico, 

October 26–27, 2004: accessed July 6, 2007, at http://www.

fig.net/pub/mexico/papers_eng/ts2_enemark_eng.pdf

Forster, C.B., and Cleveland, N.L., 2005, Dynamics of 

human - environment interaction in the U.S.-Mexican 

border region: Southwest Consortium of Environmental 

Research and Policy Monograph 11: The U.S.-Mexico 

Border Region: Dynamics of Human-Environment Interactions: accessed July 5, 2007, at http://scerp.org/pubs/m11/

chapter%201-1.pdf

Henneberger, John, 2000, Affordable housing on the border: 

Borderlines 65, v. 8, no. 3, accessed July 5, 2007, at http://

www.irc-online.org/us-mex/borderlines/2000/bl65/bl65.html

Holz, R.K., and Davies, C.S., 1992, Remote sensing techniques for population estimation of colonias in the Lower 

Rio Grande Valley of Texas: Geocarto International (2), 

p. 21–32.

Norman, L.M., Donelson, A.J., Pfeifer, E.L., and Lam, A.H., 

2006, Colonia development and land use change in Ambos 

Nogales, United States – Mexican Border: U.S. Geological 

Survey Open-File Report 2006–1112, 121 p.

Office of the Texas Secretary of State, 2006, Tracking the 

progress of state-funded projects that benefit colonias: 

accessed February 13, 2007, at http://www.sos.state.tx.us/

border/colonias/reports.shtml

Parcher, J.W., 2002, Remote sensing method for estimating 

impervious cover for hydrologic modeling applications, A 

Case Study of the Brownsville, Matamoros Area: Masters 

Thesis, University of Texas, 158 p.

Peach, J., and Williams, J., 2003, Population and economic 

dynamics on the U.S.-Mexican border: past, present, and 

future: Southwest Consortium of Environmental Research 

and Policy Monograph 1: the U.S.-Mexico Border Region: 

A Road Map to a Sustainable 2020, accessed July 5, 2007, 

at http://scerp.org/pubs/m1c4.pdf

Salinas, E., Besenberg, M., Amazeen, J. 1988, The colonias 

factbook: A survey of living conditions in rural areas of 

south Texas and west Texas border counties: Texas Department of Human Services, 68 p.

Texas Legislature Online, 2007, Senate Bill 99: accessed July 

31. 2007, at ftp://ftp.legis.state.tx.us/bills/80R/billtext/doc/

senate_bills/SB00001_SB00099/

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Texas online: accessed February 13, 2006, at http://www.

tsha.utexas.edu/handbook/online/

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world: accessed July 9, 2007, at http://www.census.gov/ipc/

www/worldpop.html

Van der Molen, Paul, 2004, Good administration of land in 

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Land Information Policies in the Americas: Aguascalientes, 

Mexico October 26–27, 2004: accessed July 6, 2007, at 

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pdf

Ward, P.M., 1999, Colonias and public policy in Texas and 

Mexico: Urbanization by stealth: Austin: University of 

Texas Press. 298 p.

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Oak Ridge National Laboratory, Oak Ridge, Tennessee, 

51 p.
Data Dictionary for CHIPS 21

Appendix A

Data Dictionary for CHIPS
22 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border Identification Field name Data type Length of field Description Colonia_ID Text 8 The TWDB M number. The format is the Letter “M” followed by a 7 digit code. This is a unique identifier that serves as the primary key that links this table with all the others. County Text 50 The county the colonia is located in. Primary_Precinct Text 1 Although the data type is text, it must be a number (ex. 3). It is the primary precinct that the colonia is in. Additional_Precincts Text 20 Additional precincts that the colonia may span. Please enter data in the following format: (2,3,4,etc.). Colonia_Name Text 50 The name of the colonia. Alternate Name(s) Text 50 A list of alternate names the colonia may have. Est Colonia Population Number Estimated population of the colonia. Color_Code Text 10 The classification of the colonia’s status. Entries are limited to {Red,Yellow,Green,Unknown} Platting Field name Data type Length of field Description Colonia_ID Text 8 The TWDB M number. The format is the Letter “M” followed by a 7 digit code. This is a unique identifier that serves as the primary key that links this table with all the others.

TWDB_OAG_DB_Status Text 10 Is the colonia in the TWDB/OAG database? Entries are limited to {Yes, No, Unknown}Is_Platted Text 10 Is the colonia platted? Entries are limited to {Yes, No, Unknown}Is_Recorded Text 11 Is the plat recorded? Entries are limited to {Yes, No, Unknown}Date_Plat_Recorded Text 20 Date the plat was recorded.Is_Mapped Text 10 Is the colonia mapped? Entries are limited to {Yes, No, Unknown}Date_Established Text 20 Date the community was established.Comments Text 255 Any additional comments regarding the platting information.
Data Dictionary for CHIPS 23

 Infrastructure

Field name Data type Length of field Description

Colonia_ID Text 8 The TWDB M number. The format is the Letter “M” followed by a 7 digit code. This is a unique identifier that 

serves as the primary key that links this table with all the others.

Public_Distribution Text 50 Does the Colonia have a public water distribution system? Entries limited to {Yes, No, Partial, Unknown}Private_Wells Text 50 Do private wells provide potable water in this colonia? Entries limited to {Yes, No, Partial, Unknown}Hauled_In Text 50 Is potable water hauled into the colonia? Entries limited to {Yes, No, Partial, Unknown}All_Lots_Potable_W Text 50 Do all lots have a potable water supply? Entries limited to {Yes, No, Unknown}WW_Collect_Avail Text 50 Is a wastewater collection system available in the colonia? Entries limited to {Yes, No, Partial, Unknown}Inadequate_WW_Disp Text 50 Are there lots served by inadequate wastewater disposal? Entries limited to {Yes, No, Partial, Unknown}Trash_Collect_Avail Text 50 Is a trash collection system available in the colonia? Entries limited to {Yes, No, Partial, Unknown}Rainfall_Flood Text 50 Does the colonia flood during rainfall? Entries limited to {Yes, No, Partial, Unknown}In_Floodplain Text 50 Is any part of the colonia in a flood plain? Entries limited to {Yes, No, Partial, Unknown}Rds_Passable Text 50 Are the streets and roads passable in all weather conditions? {Yes, No, Unknown}Rds_Paved Text 50 Are access roads from the colonia to public roads paved? {Yes, No, Partial, Unknown}Comments Text 255 Any additional comments regarding the infrastructure information.

Health Care

Field name Data type Length of field Description

Colonia_ID Text 8

The TWDB M number. The format is the Letter “M” followed by a 7 digit code. This is a unique identifier that 

serves as the primary key that links this table with all the others.

Promotoras_Avail Text 50 Are promotoras or a comparable outreach program available? Entries limited to {Yes, No, Partial, Unknown}Health_Shortage Text 50 Is it a health professional shortage? Entries limited to {Yes, No, Unknown}AM_Clinic_Avail Text 50 Is there access to an A&M Center, a clinic, mobile clinic or transportation to a clinic available? Entries limited to 

{Yes, No, Unknown}

Comments Text 255 Any additional comments regarding the health care information.
24 CHIPS: A New Way to Monitor Colonias Along the United States-Mexico Border

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