Tidal Creek Habitats

Sentinels of Coastal Health
Valuing Tidal Creeks 

Studying Tidal Creeks 

Relating Data to a Conceptual Model

Conclusions

Recommendations

Additional Resources

Glossary

Table of Contents

5

7

14

15

16

18

20

Photos/George Steele, George Riekerk, Anne Blair

Publication of this booklet is sponsored by the National Oceanic and

Atmospheric Administration through a grant administered by the S.C. Sea Grant 

Consortium, National Ocean Service Agreement MOA-2006-025/7182.
Tidal creek ecosystems are the primary aquatic link 

between stormwater runoff from the land and estuaries. 

Small tidal creeks begin in upland areas and drain into 

larger creeks forming a network. The creeks increase in 

size until they join a tidal river, sound, bay, or harbor 

that ultimately connect to the coastal ocean. The upper 

regions or headwaters of tidal creeks are “first responders” 

to stormwater runoff and are an important habitat for 

evaluating the impacts of coastal development on aquatic 

ecosystems.

Coastal development has a negative impact on tidal 

creeks and ultimately impacts public health and the 

quality of coastal living. When the amount of impervious 

cover from development, including roads, parking lots 

and roofs, in coastal watersheds exceeds 10-30 percent, 

the physical, chemical, and biological processes in tidal 

creeks are impaired and potential human uses of these 

important habitats decrease. Properties along the shores 

of developed tidal creeks become more vulnerable to 

flooding as impervious cover levels increase. 

This booklet is based on a synthesis of over 15 years of 

research in tidal creek systems. It is designed to inform 

local and state decision-makers and citizens about 

the consequences of rapid, poorly planned coastal 

development on tidal creeks and coastal communities.

Preface

Photo/George Steele

4

Many have

the attitude 

toward 

development 

that we once 

had toward 

smoking:

sure it’s bad,

but it won’t

be a problem 

for me. 

Anna

Quindlen’s 

article,

Put ‘Em in a 

Tree Museum, 

2004 

“

”
Our coastlines are alluring places for millions of people, 

residents and visitors alike. Currently, over 50 percent of 

the U.S. population lives along the coasts. With its mild 

climate and scenic vistas of tidal creeks and salt marshes, the 

Southeast is one of the fastest growing regions of the country. 

Historically, southeastern coastal development occurred on 

higher ground with deep water access. Lower elevation areas 

were sparsely developed because of their vulnerability to 

flooding, disease, and limited access to deep water. As more 

people have moved to the southeastern coast, the shores of 

low lying tidal creeks and salt marshes have become popular 

locations for building homes, resorts, and recreational 

facilities. Coastal resources annually contribute almost a 

trillion dollars to the U.S. economy. The Southeast is no 

exception with South Carolina’s coastal economy accounting 

for $40 billion in economic output in 2000 and 25 percent of 

the state’s employment growth.

Coastal ecosystems also provide society with many goods 

and services including seafood, shipping routes, recreation, 

and waste treatment. These free goods and services are critical 

for sustaining coastal communities and their economies. For 

example, tidal creeks and salt marshes are important aquatic 

nurseries providing refuge and food for juvenile fish, shrimp, 

and crabs. Red drum, spotted sea trout, spot, croaker, white 

and brown shrimp, and blue crabs represent some of the 

economically important tidal creek inhabitants. Tidal creeks 

and salt marshes also protect adjacent lands from flooding 

and the scenic vistas they provide enhance property values 

and the quality of life of homeowners. 

Regrettably, most current coastal development is proceeding 

in a manner that is costly and wasteful. For example, coastal 

growth in Charleston, S.C., is consuming forested and 

agricultural land at a rate six times greater than the growth of 

the human population. This pattern of development, called 

urban sprawl, creates communities that are highly reliant 

upon automobile use. About 65 percent of the impervious 

cover in suburban areas is for infrastructure such as roads, 

driveways, and parking lots.

Valuing Tidal Creeks 

Tidal Creek Habitats

5

Urban growth

projections for the year 

2030 (yellow) in the 

Charleston, S.C., area. 

Projections were

developed by

Clemson University

using an integrated 

modeling approach

(see Additional Resources).

[

Urban 1973

70 sqare miles

Urban 1994

180 sqare miles

Urban 2030

618 sqare miles

Non-Urban

Water
Large amounts of impervious cover in a watershed prevent 

the percolation of water into the soil and channels it 

quickly into tidal creeks. This runoff carries with it whatever 

pollutants are on the hard surfaces, including sediments, 

chemicals, bacteria, and viruses. These pollutants come from 

many hard-to-identify sources, called non-point sources, and 

impair the health of tidal creeks. The chemicals accumulate 

in creek sediments and can reach levels that harm marine 

life in developed areas. Swimming in creeks with high levels 

of fecal bacteria or eating fish and shellfish from degraded 

creeks may adversely affect human health. 

Local and state governments are responsible for approving 

almost every aspect of coastal development. As a result,

public officials control coastal development. If these officials 

and the governments they represent support a sprawl-like

growth pattern and do not conserve open space, the 

productivity, quality, beauty, and services of tidal creeks and 

other marine habitats will be impaired – possibly forever. More 

importantly, the quality of coastal living will not be sustained 

for future generations. 

Tidal creeks as sentinels

Conceptually, sentinels provide early warning of unseen threats. 

When we think of sentinel species, the canary in the coal mine 

comes to mind. Canaries were used to give miners a warning 

that the air in mines contained lethal levels of toxic gases, 

providing the miners a chance to exit before they were harmed. 

Tidal creeks, particularly their headwater areas, serve a similar 

function for our coasts and provide the first evidence of the 

impact coastal development is having on marine ecosystems and 

human health and well-being. These headwater creeks are the

primary aquatic link between land environments and estuaries 

and have limited capacity to dilute non-point source pollutants 

in runoff. Tidal creeks are, therefore, sentinel habitats that provide 

early warning of the degradation of coastal environments years 

to decades before system-wide impairment occurs.

6

[

 Impervious cover levels in the

 Charleston, S.C., area. Data source:

National Land Cover Database 2001.

0

1-10

11-20

21-30

31-100

% Impervious Cover
Tidal Creek Habitats

Over the past decade, researchers have studied more than 

40 creeks in South Carolina. Recently the research has been 

expanded into Georgia and North Carolina using sites in the 

National Estuarine Research Reserve System (NERRS) as 

representative undeveloped tidal creek habitat. Suburban 

and urban areas adjacent to NERRS sites were also sampled. 

In future years, researchers plan to include NERRS sites and 

adjacent developed areas in the Gulf of Mexico. 

Studying Tidal Creeks 7

Identify and understand the effects of

coastal development on tidal creek habitats.

Evaluate the benefits of using tidal creeks as a sentinel 

habitat for monitoring and assessment activities. 

Obtain information and develop tools to forecast the 

impacts of coastal development on tidal creek habitats. 

Develop a conceptual model linking coastal

development, tidal creek environmental quality,

and human uses to alternative management actions.

Identify ways to reduce development impacts on valued 

resources and human uses.

1.

2.

3.

4.

5.

Primary Objectives

To accomplish their objectives, tidal creek

researchers measured the following parameters

for each creek and the associated watershed. 

Development and land-use patterns including

impervious cover levels.

Water and sediment quality including nutrients,

pathogen indicators, and chemical contaminants. 

The kinds and abundance of aquatic life including

valued species like fish and shrimp as well as their prey.

Human uses including the potential to harvest shellfish. 

1.

2.

3.

4.

Measurements

Photo/George Riekerk
Coastal development and related population growth 

are the major stressors identified for tidal creek 

habitats. Coastal development stress is measured 

using human population density, land cover, and the 

amount of impervious cover in a watershed. Forested 

watersheds have less than 10 percent impervious cover 

and a population density of less than 4 people per 

acre. In contrast, suburban watersheds average about 

30 percent impervious cover and have a population 

density of about 25 people per acre. Industrial 

watersheds have low population densities (less than 

10 people per acre) compared to urban watersheds 

(greater than 40 people per acre); however, they have 

similar impervious cover levels (greater than

50 percent). In Charleston, S.C., the amount of 

impervious cover increased by about 10 percent 

between 1992 and 1999 in suburban watersheds.

This trend is expected to continue in the future for 

much of the state and region. 

8 Stressors

Observed change from 

a forested watershed 

in 1994 to a suburban 

watershed in 1999.

Aerial photos provided by 

S.C. Department of Natural 

Resources.

1994

1999
Coastal development creates two types of pollution: point 

source (originating from a discharge pipe) and non-point 

source (everything else). State and federal laws effectively 

control the amount and quality of pollution originating 

from point-source discharges. Non-point source pollution, 

called stormwater runoff, originates from many different 

sources including impervious surfaces, lawns, parks, 

and golf courses. Because non-point source pollution 

originates from diffuse sources, it is difficult to control. 

When the amount of impervious cover in a tidal creek 

watershed exceeds 10 to 20 percent, measurable 

increases in the volume and rate of stormwater runoff 

occur, resulting in impaired water quality, excessive 

amounts of harmful chemicals in sediments, and 

increases in pathogens in water and shellfish. 

Increased stormwater runoff 

Stormwater runoff is episodic or “flashy” with increasing 

levels of impervious cover. For instance, a one-acre 

parking lot produces 16 times the runoff as a one-acre 

meadow. Vegetated environments reduce the amount 

and rate of runoff and improve water quality by allowing 

runoff to percolate into the soil. In the soil, natural 

processes trap and transform pollutants into harmless 

decay products. In forested settings, only about 10 to 20 

percent of the rain that falls on the watershed enters tidal 

creeks as stormwater runoff. In suburban and urban areas, 

15 to 75 percent of rain that falls on the watershed enters 

the creek.

Highly variable water quality

The episodic runoff occurring in suburban and urban areas 

causes large fluctuations in water quality, creating poor 

nursery habitat for sensitive juvenile fish, shrimp, and 

crabs. As a result, these organisms are frequently not as 

abundant and may not develop normally in creeks with 

impaired water quality. Nutrients, such as nitrogen, which 

are abundant in runoff from suburban lawns and golf 

courses, are also more abundant in suburban and urban 

creeks in comparison to forested creeks. Excessive levels 

of nutrients can result in noxious and harmful algal blooms 

and decreases in dissolved oxygen levels.

Increased chemical contaminants in sediments 

Chemical pollutants in creek sediments provide an 

integrated measure of the chemicals that occur in the 

water over many years. The amount and kinds of chemical 

pollutants in sediments also provide an indication of 

the amount of chemical pollutants that may accumulate 

Tidal Creek Habitats

Environmental Exposures 9
10

Forested Watershed

Rainfall Evapotranspiration

Surface flow

Groundwater recharge

Stormwater 

runoff

u

u

u

Developed Watershed

Rainfall Evapotranspiration

Surface flow

Groundwater recharge

Stormwater u runoff

u

u

Visual representation of the differences in the volume and rate of stormwater runoff between an undeveloped forested watershed and a developed

urban environment. The magnitude of the differences is represented by the size of the arrows as well as the height and width of the peaks in the graphs.

2

1

0

Time (hours) 0 6 12 18 24 30 36 42 48 54 60 66

Runoff

(cubic feet

 per second )

u

u

u

u

2

1

0

Time (hours) 0 6 12 18 24 30 36 42 48 54 60 66

Runoff

(cubic feet

 per second )
in seafood. The chemicals found in tidal creek 

sediments include substances that are harmful to 

marine animals as well as chemicals that are a risk 

to human health should they occur in seafood. In 

general, the levels of sediment chemicals are slightly 

higher in suburban creeks than in forested creeks. 

However, sediment trace metal concentrations 

(copper, cadmium, lead, zinc, and mercury) are 2 to 

10 times higher in urban creeks than in suburban and 

forested creeks. Urban creeks also have substantially 

higher organic contaminants, including products from 

automobile exhausts, such as Polycyclic Aromatic 

Hydrocarbons (PAHs). The chemical contamination 

of creek sediments increases in a predictable manner 

as the amount of impervious cover in the watershed 

increases.

Tidal creek sediments were also tested for 

Polybrominated Diethyl Ethers (PBDEs) which are 

used as flame retardants in clothing, furniture, tires, 

and building materials. Although these chemicals have 

been developed to protect us, they escape from the 

products in which they are placed and accumulate in 

the environment. Once in the environment PBDEs are 

a threat to marine life and humans. PBDEs occur in 

the sediments of urban and a few suburban creeks but 

do not occur in forested creeks. 

Similarly, pharmaceuticals have been developed to treat 

human and animal diseases. Unfortunately, we do not 

fully utilize the drugs we take, and sewage treatment 

facilities and septic systems are not designed to remove 

pharmaceuticals or their decay products from wastewater 

before it is released into creeks and rivers. People often 

dispose of excess pharmaceuticals by flushing them into 

wastewater systems. Once released into the environment 

pharmaceuticals can harm marine life. A potentially 

important consequence of excessive release of antibiotics 

is an increase in the abundance of antibiotic resistant 

bacteria in the environment. Antibiotic resistant bacteria, 

as well as trace levels of pharmaceuticals, are found in 

tidal creeks as well as in some shellfish.

Indicators of human pathogens 

Fecal coliform bacteria are found in the digestive tracts of 

warm-blooded animals including mammals and birds as well 

as some cold-blooded animals. These bacteria are used as 

indicators of the presence of pathogens in the environment. 

Humans typically ingest pathogens from eating contaminated 

shellfish and by ingesting contaminated water during 

swimming. Most states close shellfish grounds to 

harvesting when the number of fecal coliform bacteria 

exceeds about 50 colony forming units (CFU) per

Tidal Creek Habitats

1 1
100 ml of water, and water contact recreation is 

generally prohibited when fecal coliform levels exceed 

about 400 CFU per 100 ml of water. 

The level of fecal coliform contamination increases 

when the amount of impervious cover in tidal creek 

watersheds increases. Most of the creeks, including 

many undeveloped forested creeks, do not meet the 

fecal coliform standard for shellfish harvesting or 

swimming. The source of most of the fecal coliform 

contamination at forested sites is wildlife. The high fecal 

coliform levels in suburban areas are most likely due to 

pets and wildlife. Extremely high fecal coliform levels 

in urban creeks are from multiple sources, including 

human sewage. Because many human diseases originate 

from pathogens associated with domestic animals and 

wildlife, consumption of seafood or swimming in water 

containing large numbers of fecal bacteria represents a 

human health risk.

Biological Responses

Tidal creeks and their associated salt marshes are 

important nursery habitats for juvenile fish, shrimp, 

and crabs. Organisms living in tidal creeks respond to 

increases in pollution associated with coastal development in a 

variety of ways. The abundance of pollution-sensitive animals, 

such as edible shrimp and important food items in the diets of 

fish, decline as impervious cover levels in watersheds increase. 

Impairment to marine life is most severe when impervious 

cover levels exceed 20-30 percent. Pollution-tolerant worms 

are very abundant in urban creeks and accumulate high levels 

of contaminants in their bodies which may be transferred to 

the fish and shellfish that eat them. Highly developed urban 

creeks also have simple food webs, low abundances of edible 

marine life, and are poor nursery habitats.

A number of pollution tolerant

worms are found in higher numbers

in developed creeks. Photo/John Weinstein

White and brown shrimp rely on 

tidal creek nursery habitats.

Photo/George Riekerk

12

Almost

one-third of 

South Carolina 

shellfish 

harvesting areas 

are closed 

because the 

consumption 

of oysters from 

these areas 

could pose 

health risks. 

Webster et al., 

2004

“

”
Societal Responses 

As impervious cover levels and coastal 

development increase, human uses of tidal 

creek habitats decrease, adversely affecting the 

quality of coastal living. These changes ultimately 

impact the attitudes and values society places on 

coastal environments. For example, degradation 

of tidal creek water quality decreases seafood 

harvesting opportunities and the recreational use 

of these beautiful and accessible habitats. Almost 

none of the developed creeks studied support 

shellfish harvesting and most suburban and urban 

creeks do not meet the water quality criteria for 

recreational use. In addition, higher levels of 

impervious cover increase the vulnerability of 

adjacent land to flooding after large rain events. 

This episodic flooding adversely affects traffic 

infrastructure and homeowners. Correction 

of flooding problems will be at a substantial 

economic cost to coastal communities because 

they will require modifications to stormwater 

infrastructure. Increases in homeowner insurance 

costs and decreases in property values are likely 

consequences over the long term.

Tidal Creek Habitats

13

Acceptable Marginally 

Impaired Impaired

Watershed

Forested

Suburban

Urban

Industrial

Water Bacterial Sediment Aquatic 

Life

Human 

Use

Tidal Creek Habitat Report Card
14 Relating Data to a Conceptual Model

A conceptual ecosystem model is a visual 

representation of the relationships between an 

environmental stressor (coastal development) 

and the physical, chemical, and biological 

components and processes that make up an 

ecosystem, including humans. The adjacent 

diagram is a conceptual model that identifies the 

important connections and relationships between:

This model provides planners and decisionmakers a tool for understanding how alternative 

management actions may affect the goods and 

services society wants to preserve and sustain in 

tidal creeks.

coastal development

and population growth,

physical and chemical changes

including water quality,

biological responses of fish

and shellfish, and

societal responses such as not allowing 

humans to harvest the shellfish.

•

•

•

•

Conceptual Model of Tidal Creek Watershed Linkages

Coastal

Development

Activities

PhysicalChemical

Changes

Health

and

Well Being

Stressor Exposure

u u u

Biological

Response

Societal

Response

Increases 

population density

Alters land cover

Increases 

impervious surface

Alters water quality 

and hydrography

Increases microbial 

contamination

Increases chemical 

contamination

Reduces biological 

productivity

Alters food webs

Impairs animal 

health

Increases beach 

and shellfish bed 

closures

Increases

flooding

Increases public 

health risk and 

economic impact

10-20%

Impervious cover

20-30%

Impervious cover

Being

determined

Management Actions

u

u

uuu

Living

Resources

Impacts
Tidal Creek Habitats

15

In conclusion, tidal creeks, particularly the headwater 

portions, provide early warning of the impacts from 

coastal development on estuaries. The message derived 

from recent studies of tidal creeks is straightforward: 

The types and levels of watershed development greatly 

influence the amount of stormwater runoff and pollution 

that is released into coastal waters. Poorly planned or 

sprawling development patterns that create large amounts 

of impervious cover adversely affect the biological 

integrity and human uses and benefits derived from 

tidal creek habitats. The following impacts have been 

documented:

Conclusions

u

u

u

Changes in the kinds and abundance 

of food web organisms indicate the 

degree to which creeks can no longer 

support the production of fish and 

shellfish. 

Decreased abundance of harvestable 

shrimp indicates the degree to which 

nursery grounds have been harmed.

Increased vulnerability of headwater 

creeks to flooding indicates potential 

property depreciation and lessened 

quality of life in coastal communities.

Episodic or “flashy” runoff indicates the 

extent to which natural creek flow has 

been altered.

Increased amounts of chemicals 

in sediments indicate the extent of 

chemical contamination and the degree 

to which seafood may be contaminated. 

Increased pathogen levels indicate the 

degree to which swimming and shellfish 

harvesting opportunities have been 

impaired.

u

u

u
A concerted public education effort will foster and encourage 

permanent protection of watersheds and the important goods 

and services they provide society. The best strategy for conserving 

tidal creek environmental quality is planning for development 

at a variety of scales, including regional, watershed, community, 

and site level, with the goal of minimizing the amount of 

stormwater runoff and maximizing the quality of runoff. 

Regionally, infrastructure planning and zoning are the most 

effective approaches for determining where new development 

should occur; however, zoning and ordinances only protect 

the land until the next Land-Use Plan or until a new municipal 

official is elected.

Recommendations

Purchasing Development Rights (PDR) 

programs and land conservation easements to 

provide permanent land protection. 

Encouraging or requiring alternative and 

mixed-use designs that maximize street and 

community connectivity, protect open space, 

and minimize vehicle use. 

Recommendations at the municipality u and county scale 

16

Planning development activities that: 

• limit alterations to freshwater inflows into

tidal creeks, 

• minimize the amount of impervious surface, 

• require naturally vegetated buffers, and • maximize the amount of vegetated open space. 

Preparing and publishing guidelines and standards 

for development that prevent pollution from 

entering valuable tidal creek and marsh habitats. 

Creating a land conservation ethic that encourages 

stewardship of tidal creeks and marshes. 

Evaluating development on a watershed basis. 

Limiting the amount and kind of pollutants 

released into tidal creeks. 

Establishing permanent land trusts for critical 

habitats within tidal creek watersheds. 

Considering implementing an impervious cover 

trading program similar to air pollution trading.

Periodically monitoring and assessing the status 

and trends of tidal creeks and reporting their 

condition to the public. 

Recommendations at the watershed or u neighborhood planning scale

•

•

•

•

•

•

•

•

•

•
Tidal Creek Habitats

17

Minimizing the amount of new impervious cover

that is created on one’s property.

Using pervious alternatives such as porous concrete

and pavers.

Directing surface water runoff into swales and vegetated 

buffers to trap pollutants and increase infiltration, 

allowing slower movement of stormwater to creeks. 

Maintaining naturally vegetated open spaces and buffers 

to decrease the amount and rate of runoff. 

Designing and implementing bioretention cells, rain 

gardens, and/or constructed wetlands to provide added 

treatment of stormwater.

Following label directions when applying fertilizers and 

pesticides as well as properly storing and disposing of 

these hazardous household products.

Disposing of trash properly and recycling when possible. 

Picking up and properly disposing of pet wastes

(pooper scooper programs). 

u Recommendations at the site or homeowner scale

•

•

•

•

•

•

•

•

Depressing, brutal, 

ugly, unhealthy, 

and spiritually 

degrading. 

James Kunstler 

1944

Sprawl is bad 

aesthetics; it is 

bad economics. 

Five acres is 

being made to 

do the work of 

one, and do it 

poorly. This is bad 

for the farmers, 

it is bad for the 

communities, it is 

bad for industry, 

it is bad for 

utilities, it is bad 

for recreational 

groups, it is 

even bad for the 

developers. 

William Whyte 

1958

“

”

“

”

...a form of 

urbanization 

distinguished by 

leapfrog patterns 

of development, 

commercial 

strips, low density, 

separated land 

uses, automobile 

dominance and a 

minimum of public 

open space. 

Oliver Gillham 

2002

Sprawl is a costly 

and wasteful form 

of development 

that unnecessarily 

degrades natural 

systems, adversely 

affects human 

safety and 

health, and is not 

economically 

sustainable. Sprawl 

represents a poor 

quality of life.

Fred Holland

2007

“

”

“

”

Sprawling development through the years
Many organizations support programs that provide information 

about the impacts of development on coastal environments 

and communities. The following entities provide information 

related to protecting and studying tidal creeks. 

The Hollings Marine Laboratory (HML) is one of NOAA’s 

five National Centers for Coastal Ocean Science (NCCOS) 

and is a partnership among the South Carolina Department 

of Natural Resources, Medical University of South Carolina, 

National Oceanic and Atmospheric Administration,

the National Institute of Standards and Technology, and

the College of Charleston. The tidal creeks conceptual

model serves as an integrative framework for

environmental and public health research at the 

laboratory. For more information, visit HML at

www.hml.noaa.gov or call 843.762.8811. 

The Oceans and Human Health Initiative (OHHI) seeks to 

improve our understanding and management of the coasts 

to enhance benefits to human health and reduce public 

health risks. This is achieved by developing new methods 

and approaches to identify and characterize chemical and 

microbial threats to marine ecosystems and human health

as well as to evaluate the health responses of marine 

organisms and ecosystems to stress. For more information, 

visit www.eol.ucar.edu/projects/ohhi.

The Center for Coastal Environmental Health and 

Biomolecular Research (CCEHBR) is also one of NCCOS’s 

five national centers and conducts interdisciplinary 

research to resolve issues related to coastal ecosystem 

health, environ-mental quality, and related public health 

impacts. Visit CCEHBR at www.chbr.noaa.gov.

The South Carolina Sea Grant Consortium (SCSGC) is 

a science-based state agency that seeks to enhance the 

practical use and conservation of South Carolina’s coastal 

and marine resources through research, education, and 

extension programs. Contact the SCSGC for a homeowner’s 

water-quality guide, Coast-A-Syst, for information about the 

S.C. Nonpoint Education or Municipal Officials (SCNEMO) 

program. Visit the SCSGC at www.scseagrant.org. 

The South Carolina Department of Natural Resources

(SCDNR) is a state agency that is an advocate for and 

steward of the state’s natural resources by regulating fishing, 

boating, and hunting. Visit SCDNR at www.dnr.sc.gov. 

The South Carolina Department of Health and 

Environmental Control’s Office of Ocean and Coastal 

Resource Management (SCDHEC-OCRM) is a state agency 

that is responsible for protecting South Carolina’s coastal 

environment while promoting responsible development

Points of Contact

Dr. Fred Holland 

Fred.Holland@

noaa.gov 

Dr. Denise Sanger

Denise.Sanger@

scseagrant.org

Additional Resources

u

18
along the state’s coast. Visit SCDHEC-OCRM at

www.scdhec.gov/environment/ocrm. 

The South Atlantic Bight Land Use-Coastal Ecosystem Study

(LU-CES) was an interdisciplinary S.C. Sea Grant research program 

designed to understand the effects of changing land-use 

patterns on coastal resources. Visit LU-CES at www.lu-ces.org. 

The Urbanization and Southeastern Estuarine Systems (USES) 

Project was a study that assessed and modeled the effects of 

urban development on small, high salinity estuaries on the 

southeastern coast of the United States. Visit USES at

www.urbanestuary.org. 

The Growth Projection Study was a modeling effort by 

Clemson University’s Strom Thurmond Institute of Government 

and Public Affairs to predict the future urban growth in the 

Charleston area. The predictions were based on an integrated 

GIS model. It is not expected that real growth will exactly 

follow the predicted patterns. Visit www.strom.clemson.edu/

teams/dctech/urban.html for additional information.

The National Estuarine Research Reserve System (NERRS) is a 

network of protected areas established for long-term research, 

education, and stewardship. For more information, visit NERRS 

at www.nerrs.noaa.gov.

Tidal Creek Habitats

19

An Ocean Blueprint for the 21st Century is a 2004 

report by the U.S. Commission on Ocean Policy 

which provides recommendations for a new national 

policy for the ocean. Visit www.oceancommission.gov

to review the document.

Photo/

George Steele

Photo/

George Steele
Ecosystems are systems formed by complex communities 

of organisms and their physical environment. Tidal creeks 

research includes humans as part of the coastal ecosystem.

Estuaries are diverse, semi-enclosed coastal bodies of 

water where seawater and freshwater mix. 

Fecal coliform bacteria are a collection of microorganisms 

that live in the intestines of humans and other warm- and 

cold-blooded animals. High fecal coliform concentrations 

can indicate the presence of harmful viruses and bacteria. 

Impervious cover is the percentage or ratio of impervious 

surfaces such as roofs, roads, parking lots, and other hard 

materials that water cannot penetrate, relative to the total 

land area. 

Land cover is the nature of the surface of a 

watershed which includes forests, suburban and 

urban areas, rivers and lakes, and wetlands. There 

are two primary methods for obtaining information 

on land cover: field surveys and analysis of remotely 

sensed images of the landscape.

Non-point source pollution cannot be traced to a 

specific source but comes from multiple generalized 

sources, such as residential developments, 

farmlands, stormwater ponds, and parking lots that 

drain from watersheds into the receiving water 

bodies. 

Polycyclic aromatic hydrocarbons (PAHs) are 

carcinogenic chemicals that are formed when fossil 

fuels are not completely combusted. 

Purchase of development rights (PDR) programs 

channel development from rural areas into already 

developed areas by using public funds to purchase 

the development rights for rural properties in 

perpetuity. 

Stressors are agents that cause stress to an organism, 

population, or ecosystem. 

20 Glossary

Photo/

George 

Steele
Urban sprawl is the spreading out of development into 

rural lands in a manner where residents tend to live in 

single-family homes and commute by automobile to work. 

Vegetated buffers are areas covered in vegetation 

generally occurring between the development and a 

water body. The vegetation slows down stormwater runoff, 

promotes groundwater recharge, and filters pollutants. 

Watersheds are the land area surrounding a particular 

water body – streams, rivers, ponds, and lakes – into 

which runoff drains. Watershed boundaries are generally 

based on elevation.

Swales are engineered drainage areas that are low, 

narrow tracts of land which allow water to percolate 

into the ground as they convey water to a receiving 

water body.

Tidal creeks connect uplands and marshes to larger 

estuarine and coastal water bodies. 

Tidal Creek Habitats

21

Photo/

George 

Riekerk

Photo/

April 

Turner

Photo/

SCDHECOCRM
22

Photo/Anne Blair
SCSGC-G-08-04