Delaware community action

Climate change in Delaware encompasses the effects of climate change, attributed to man-made increases in atmospheric carbon dioxide, in the U.S. state of Delaware.

According to the United States Environmental Protection Agency (EPA), "Delaware's climate is changing. The state has warmed two degrees (F) in the last century, heavy rainstorms are more frequent, and the sea is rising about one inch every seven years. Higher water levels are eroding beaches, submerging low lands, exacerbating coastal flooding, and increasing the salinity of estuaries and aquifers. In the coming decades, changing the climate is likely to increase coastal flooding; harm marine, wetland, and inland ecosystems; disrupt farming; and increase some risks to human health".

According to the EPA, "sea level is rising more rapidly along the Delaware coast than in most coastal areas because Delaware is sinking. If the oceans and atmosphere continue to warm, sea level is likely to rise between sixteen inches and four feet along the Delaware coast in the next century. As sea level rises, the lowest dry lands are submerged and become either tidal wetland or open water. Wetlands can createtheir own land and keep pace with a slowly rising sea. But if sea level rises three feet or more in the next century, most existing tidal wetlands in Delaware are unlikely to keep pace but will instead become tidal mud flats or shallow open water. Existing tidal flats will generally convert to open water as they are submerged".

The EPA further reports that "beaches also erode as sea level rises. A higher ocean level makes it more likely that storm waters will wash over a barrier island or open new inlets. The United States Geological Survey estimates that Fenwick Island could be broken up by new inlets or lost to erosion if sea level rises three feet by the year 2100, unless people take measures to reduce erosion. Estuarine beaches may also be eliminated in some areas. Many of Delaware Bay's beaches are narrow, with wetlands immediately inland. Along parts of Delaware Bay and the Delaware River, people have built walls or other shore protection structures that eliminate the beach once the shore erodes up to them". However, despite the state spending millions of dollars on beach restoration, experts project that shoreline erosion "will only intensify as sea levels rise from global warming".

According to the EPA, "rising temperatures and shifting rainfall patterns are likely to increase the intensity of both floods and droughts. Average annual precipitation in Delaware has increased a few percent in the last century, and precipitation from extremely heavy storms has increased in the eastern United States by more than 25 percent since 1958. During the next century, annual precipitation and the frequency of heavy downpours are likely to keep rising. Precipitation is likely to increase during winter and spring, but not change significantly during summer and fall. Rising temperatures will melt snow earlier in spring and increase evaporation, and thereby dry the soil during summer and fall. As a result, climate change is likely to intensify flooding during winter and spring, and drought during summer and fall.

According to the EPA, "the loss of tidal marshes could harm fish, reptiles, and birds that depend on a marsh for food or shelter. Blue crab, perch, weakfish, flounder, and rockfish rely on the tidal marshes in Delaware Bay to hide from predators and to feed on mussels, fiddler crabs, and other species. Sea turtles and shorebirds feed on some of the species that inhabit these marshes. Great blue herons, black ducks, ospreys, red-winged blackbirds, and several other bird species also use the salt marshes in Delaware Bay. As marshes erode, fish may benefit initially as more tidal channels form, which would make more marsh accessible. But after a point, erosion would make less marsh available, and populations of fish and birds would decline. The loss of bay beaches and tidal flats would also threaten some species. Delaware Bay is a major stopover area for six species of migratory shorebirds that feed on its beaches and tidal flats, including most of the Western Hemisphere’s red knot population. Nearly a million birds feed on the horseshoe crab eggs on the bay’s sandy beaches. Diamondback terrapin nest on estuarine beaches along Delaware’s inland bays".

The EPA further reports that "changing temperatures could also disrupt ecosystems. If water temperatures exceed 86°F during summer, eelgrass could be lost, which would remove a key source of food for many fish. Wildflowers and woody perennials are blooming—and migratory birds are arriving—sooner in spring. Not all species adjust in the same way, however, so the food that one species needs may no longer be available when that species arrives on its migration".

According to the EPA, "as sea level rises, salt water can mix farther inland or upstream in bays, rivers, and wetlands. Because water on the surface is connected to ground water, salt water can also intrude into aquifers near the coast. Soils may become too salty for the crops and trees that currently grow in low-lying areas".

According to the EPA, "towns along the Delaware shore shore will be increasingly vulnerable to storms and erosion as sea level rises. While hurricanes are rare, their wind speeds and rainfall intensities are likely to increase as the climate warms. Rising sea level is likely to increase flood insurance rates, while more frequent storms could increase deductibles for wind damage in homeowner insurance policies. Storms can destroy coastal homes, wash out highways and rail lines, and damage essential communication, energy, and wastewater management infrastructure".

According to the EPA, "changing the climate will have both harmful and beneficial effects on farming. Hotter summers are likely to reduce yields of corn. But higher concentrations of atmospheric carbon dioxide increase crop yields, and that fertilizing effect is likely to offset the harmful effects of heat on soybeans, assuming that adequate water is available. Although most chickens are raised indoors, warmer temperatures could reduce the productivity of livestock raised outside".

In December 2019, Delaware joined consideration for a multi-state gasoline cap-and-trade program. The plan aims to reduce transportation-related tailpipe emissions, and would levy a tax on fuel companies based on carbon dioxide emissions. The most ambitious version of the plan is projected to reduce the area's tailpipe emissions by 25% between 2022 and 2032. The program is in the public comment phase, with individual states determining whether to participate. The program could begin as early as 2022.

• List of U.S. states and territories by carbon dioxide emissions
• Plug-in electric vehicles in Delaware

Dupigny-Giroux, L.A.; E.L. Mecray; M.D. Lemcke-Stampone; G.A. Hodgkins; E.E. Lentz; K.E. Mills; E.D. Lane; R. Miller; D.Y. Hollinger; W.D. Solecki; G.A. Wellenius; P.E. Sheffield; A.B. MacDonald; C. Caldwell (2018). "Northeast". In Reidmiller, D.R.; C.W. Avery; D.R. Easterling; K.E. Kunkel; K.L.M. Lewis; T.K. Maycock; B.C. Stewart (eds.). Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment, Volume II (Report). Washington, DC, USA: U.S. Global Change Research Program. pp. 669–742. doi:10.7930/NCA4.2018.CH18.—this chapter of the National Climate Assessment covers Northeast states

Delaware ( DEL-ə-wair) is a state in the Mid-Atlantic region of the United States. It borders Maryland to its south and west, Pennsylvania to its north, New Jersey to its northeast, and the Atlantic Ocean to its east. The state's name derives from the adjacent Delaware Bay, which in turn was named after Thomas West, 3rd Baron De La Warr, an English nobleman and the Colony of Virginia's first colonial-era governor.

Delaware occupies the northeastern portion of the Delmarva Peninsula, and some islands and territory within the Delaware River. It is the 2nd smallest and 6th least populous state, but also the 6th most densely populated. Delaware's most populous city is Wilmington, and the state's capital is Dover, the 2nd most populous city in Delaware. The state is divided into three counties, the fewest number of counties of any of the 50 U.S. states; from north to south, the three counties are: New Castle County, Kent County, and Sussex County. The southern two counties, Kent and Sussex counties, historically have been predominantly agrarian economies. New Castle is more urbanized and is considered part of the Delaware Valley metropolitan statistical area that surrounds and includes Philadelphia, the nation's sixth most populous city. Delaware is considered part of the Southern United States by the U.S. Census Bureau, but the state's geography, culture, and history are a hybrid of the Mid-Atlantic and Northeastern regions of the country.

Before Delaware coastline was explored and developed by Europeans in the 16th century, the state was inhabited by several Native American tribes, including the Lenape in the north and Nanticoke in the south. The state was first colonized by Dutch traders at Zwaanendael, near present-day Lewes, Delaware, in 1631. Delaware was one of the Thirteen Colonies that participated in the American Revolution and American Revolutionary War, in which the American Continental Army, led by George Washington, defeated the British, ended British colonization and established the United States as a sovereign and independent nation. On December 7, 1787, Delaware was the first state to ratify the Constitution of the United States, earning it the nickname "The First State".

Since the turn of the 20th century, Delaware has become an onshore corporate haven whose corporate laws are deemed appealing to corporations; over half of all New York Stock Exchange-listed corporations and over three-fifths of the Fortune 500 are legally incorporated in the state.

Delaware was named after Delaware Bay, which in turn derived its name from Thomas West, 3rd Baron De La Warr (1577–1618), the first governor of the Colony of Virginia. The Delaware people, a name used by Europeans for Lenape people Indigenous to the Delaware Valley, also derive their name from the same source.

The name de La Warr is from Sussex and of Anglo-French origin. It came probably from a Norman lieu-dit La Guerre. This toponymic likely derived from Latin ager, the Breton gwern or from the Late Latin varectum (fallow). The toponyms Gara, Gare, Gaire, (the sound [ä] often mutated in [æ]) also appear in historical texts cited by Lucien Musset, where the word ga(i)ra means gore. It could also be linked with a patronymic from the Old Norse verr.

Before Delaware was settled by European colonists, the present-day state was home to the Eastern Algonquian tribes known as the Unami Lenape, or Delaware, who lived mostly along the coast, and the Nanticoke who occupied much of the southern Delmarva Peninsula. John Smith also shows two Iroquoian tribes, the Kuskarawock and Tockwogh, living north of the Nanticoke—they may have held small portions of land in the western part of the state before migrating across the Chesapeake Bay. The Kuskarawocks were most likely the Tuscarora.

The Unami Lenape in the Delaware Valley were closely related to Munsee Lenape tribes along the Hudson River. They had a settled hunting and agricultural society, and they rapidly became middlemen in an increasingly frantic fur trade with their ancient enemy, the Minqua or Susquehannock. With the loss of their lands on the Delaware River and the destruction of the Minqua by the Iroquois of the Five Nations in the 1670s, the remnants of the Lenape who wished to remain identified as such left the region and moved over the Allegheny Mountains by the mid-18th century. Generally, those who did not relocate out of the state of Delaware were baptized, became Christian and were grouped together with other persons of color in official records and in the minds of their non-Native American neighbors.

The Dutch were the first Europeans to settle in present-day Delaware in the middle region by establishing a trading post at Zwaanendael, near the site of Lewes in 1631. Within a year, all the settlers were killed in a dispute with Native American tribes living in the area. In 1638, New Sweden, a Swedish trading post and colony, was established at Fort Christina (now in Wilmington) by Peter Minuit at the head of a group of Swedes, Finns and Dutch. The colony of New Sweden lasted 17 years. In 1651, the Dutch, reinvigorated by the leadership of Peter Stuyvesant, established a fort at present-day New Castle and, in 1655, they conquered the New Sweden colony, annexing it into the Dutch New Netherland. Only nine years later, in 1664, the Dutch were conquered by a fleet of English ships by Sir Robert Carr under the direction of James, the Duke of York. Fighting off a prior claim by Cecil Calvert, 2nd Baron Baltimore, Proprietor of Maryland, the Duke passed his somewhat dubious ownership on to William Penn in 1682. Penn strongly desired access to the sea for his Pennsylvania province and leased what then came to be known as the "Lower Counties on the Delaware" from the Duke.

Penn established representative government and briefly combined his two possessions under one General Assembly in 1682. However, by 1704 the province of Pennsylvania had grown so large their representatives wanted to make decisions without the assent of the Lower Counties, and the two groups of representatives began meeting on their own, one at Philadelphia, and the other at New Castle. Penn and his heirs remained proprietors of both and always appointed the same person Governor for their province of Pennsylvania and their territory of the Lower Counties. The fact that Delaware and Pennsylvania shared the same governor was not unique; from 1703 to 1738, New York and New Jersey shared a governor. Massachusetts and New Hampshire also shared a governor for some time.

Dependent in early years on indentured labor, Delaware imported more slaves as the number of English immigrants decreased with better economic conditions in England. The colony became a slave society and cultivated tobacco as a cash crop, although English immigrants continued to arrive.

Like the other middle colonies, the Lower Counties on the Delaware initially showed little enthusiasm for a break with Britain. The citizenry had a good relationship with the Proprietary government, and generally were allowed more independence of action in their Colonial Assembly than in other colonies. Merchants at the port of Wilmington had trading ties with the British.

New Castle lawyer Thomas McKean denounced the Stamp Act in the strongest terms, and Kent County native John Dickinson became the "Penman of the Revolution". Anticipating the Declaration of Independence, Patriot leaders Thomas McKean and Caesar Rodney convinced the Colonial Assembly to declare itself separated from British and Pennsylvania rule on June 15, 1776. The person best representing Delaware's majority, George Read, could not bring himself to vote for a Declaration of Independence. Only the dramatic overnight ride of Caesar Rodney gave the delegation the votes needed to cast Delaware's vote for independence.

Initially led by John Haslet, Delaware provided one of the premier regiments in the Continental Army, known as the "Delaware Blues" and nicknamed the "Blue Hen's Chicks". In August 1777 General Sir William Howe led a British army through Delaware on his way to a victory at the Battle of Brandywine and capture of the city of Philadelphia. The only real engagement on Delaware soil was the Battle of Cooch's Bridge, fought on September 3, 1777, at Cooch's Bridge in New Castle County, although there was a minor Loyalist rebellion in 1778.

Following the Battle of Brandywine, Wilmington was occupied by the British, and State President John McKinly was taken prisoner. The British remained in control of the Delaware River for much of the rest of the war, disrupting commerce and providing encouragement to an active Loyalist portion of the population, particularly in Sussex County. Because the British promised slaves of rebels freedom for fighting with them, escaped slaves flocked north to join their lines.

Following the American Revolution, statesmen from Delaware were among the leading proponents of a strong central United States with equal representation for each state.

Many colonial settlers came to Delaware from Maryland and Virginia, where the population had been increasing rapidly. The economies of these colonies were chiefly based on labor-intensive tobacco and increasingly dependent on African slaves because of a decline in working class immigrants from England. Most of the English colonists had arrived as indentured servants (contracted for a fixed period to pay for their passage), and in the early years the line between servant and slave was fluid.

Most of the free African-American families in Delaware before the Revolution had migrated from Maryland to find more affordable land. They were descendants chiefly of relationships or marriages between white servant women and enslaved, servant or free African or African-American men. Under slavery law, children took the social status of their mothers, so children born to white women were free, regardless of their paternity, just as children born to enslaved women were born into slavery. As the flow of indentured laborers to the colony decreased with improving economic conditions in England, more slaves were imported for labor and the caste lines hardened.

By the end of the colonial period, the number of enslaved people in Delaware began to decline. Shifts in the agriculture economy from tobacco to mixed farming resulted in less need for slaves' labor. In addition local Methodists and Quakers encouraged slaveholders to free their slaves following the American Revolution, and many did so in a surge of individual manumissions for idealistic reasons. By 1810, three-quarters of all blacks in Delaware were free. When John Dickinson freed his slaves in 1777, he was Delaware's largest slave owner with 37 slaves. By 1860, the largest slaveholder owned 16 slaves.

Although attempts to abolish slavery failed by narrow margins in the legislature, in practical terms the state had mostly ended the practice. By the 1860 census on the verge of the Civil War, 91.7% of the black population were free; 1,798 were slaves, as compared to 19,829 "free colored persons".

An independent black denomination was chartered in 1813 by freed slave Peter Spencer as the "Union Church of Africans". This followed the 1793 establishment in Philadelphia of the African Methodist Episcopal Church by Richard Allen, which had ties to the Methodist Episcopal Church until 1816. Spencer built a church in Wilmington for the new denomination. This was renamed as the African Union First Colored Methodist Protestant Church and Connection, more commonly known as the A.U.M.P. Church. In 1814, Spencer called for the first annual gathering, known as the Big August Quarterly, which continues to draw members of this denomination and their descendants together in a religious and cultural festival.

Delaware voted against secession on January 3, 1861, and so remained in the Union. While most Delaware citizens who fought in the war served in the regiments of the state, some served in companies on the Confederate side in Maryland and Virginia Regiments. Delaware is notable for being the only slave state from which no Confederate regiments or militia groups were assembled. Delaware essentially freed the few slaves who were still in bondage shortly after the Civil War but rejected the 13th, 14th, and 15th Amendments to the Constitution; the 13th Amendment was rejected on February 8, 1865, the 14th Amendment was rejected on February 8, 1867, and the 15th Amendment was rejected on March 18, 1869. Delaware officially ratified the 13th, 14th, and 15th amendments on February 12, 1901.

During the Reconstruction Era that followed the Civil War, Democratic Redeemer governments led by the South's Bourbon aristocracy continued to dominate the region and imposed explicitly white supremacist regimes in the former slave states. The Delaware legislature declared Black people to be second-class citizens in 1866, and restricted their voting rights despite the 15th Amendment, ensuring continued Democratic success in the state throughout most of the 19th century. Fearful that the 1875 Civil Rights Act passed by Congress might establish racial equality, Delaware legislators passed Jim Crow laws that mandated segregation in public facilities. The state's educational system was segregated by operation of law. Delaware's segregation was written into the state constitution, which, while providing at Article X, Section 2, that "no distinction shall be made on account of race or color", nonetheless required that "separate schools for white and colored children shall be maintained."

Beginning in the late 19th century, the Wilmington area grew into a manufacturing center. Investment in manufacturing in the city grew from $5.5 million in 1860 to $44 million in 1900. The most notable manufacturer in the state was the chemical company DuPont, which to this day is heavily credited with making the state what it is today in many ways. Because of Wilmington's growth, local politicians from the city and New Castle County pressured the state government to adopt a new constitution providing the north with more representation. However, the subsequent 1897 constitution did not proportionally represent the north and continued to give the southern counties disproportionate influence.

As manufacturing expanded, businesses became major players in state affairs and funders of politicians through families such as the Du Ponts. Republican John Addicks attempted to buy a US Senate seat multiple times in a rivalry with the Du Ponts until the passage of the 17th Amendment. The allegiance of industries with the Republican party allowed them to gain control of the state's governorship throughout most of the 20th century. The GOP ensured black people could vote because of their general support for Republicans and thus undid restrictions on Black suffrage.

Delaware benefited greatly from World War I because of the state's large gunpowder industry. DuPont, the most dominant business in the state by WWI, produced an estimated 40% of all gunpowder used by the Allies during the war. It produced nylon in the state after the war and began investments into General Motors. Additionally, the company invested heavily in the expansion of public schools in the state and colleges such as the University of Delaware in the 1910s and 1920s. This included primary and secondary schools for Black people and women. Delaware suffered less during the Great Depression than other states, but the depression spurred further migration from the rural south to urban areas.

Like in World War I, the state enjoyed a big stimulus to its gunpowder and shipyard industries in World War II. New job opportunities during and after the war in the Wilmington area coaxed Black people from the southern counties to move to the city. The proportion of blacks constituting the city's population rose from 15% in 1950 to over 50% by 1980. The surge of Black migrants to the north sparked white flight, in which middle class whites moved from the city to suburban areas, leading to de facto segregation of Northern Delaware's society. In the 1940s and 1950s, Delaware attempted to integrate its schools, although the last segregated school in the state did not close until 1970. The University of Delaware admitted its first black student in 1948, and local courts ruled that primary schools had to be integrated. Delaware's integration efforts partially inspired the US Supreme Court's decision in Brown v. Board of Education, which found racial segregation in United States public schools to be unconstitutional. The result of the Brown ruling was that Delaware became fully integrated, albeit with time and much effort.

In October 1954, the city of Milford became the scene of one of the country's first pro-segregation boycotts after eleven Black students were enrolled in the previously all-white Milford High School. Mass protests continued in Milford; the school board eventually ceded to the protestors, expelling the Black students. The ensuing unrest, which included cross burnings, rallies, and pro-segregation demonstrations, contributed to desegregation in most of Southern Delaware being delayed for another ten years. Sussex County did not start closing or integrating its segregated schools until 1965, 11 years after the Brown ruling. Throughout the state, integration only encouraged more white flight, and poor economic conditions for the black population led to some violence during the 1960s. Riots broke out in Wilmington in 1967 and again in 1968 in response to the assassination of Martin Luther King Jr, after which the National Guard occupied the city for nine months to prevent further violence.

Since WWII, the state has been generally economically prosperous and enjoyed relatively high per capita income because of its location between major cities like Philadelphia, New York, and Washington, DC. Its population grew rapidly, particularly in the suburbs in the north where New Castle county became an extension of the Philadelphia metropolitan area. Americans, including migrants from Puerto Rico, and immigrants from Latin America flocked to the state. By 1990, only 50% of Delaware's population consisted of natives to the state.

Delaware is 96 miles (154 km) long and ranges from 9 to 35 miles (14 to 56 km) across, with a land area of 1,982 square miles (5,130 km²) and a total area of 2,489 square miles (6,450 km²), making it the second-smallest state by either metric in the United States after Rhode Island. Delaware is bounded to the north by Pennsylvania; to the east by the Delaware River, Delaware Bay, New Jersey, and the Atlantic Ocean; and to the west and south by Maryland. Small portions of Delaware are also situated on the eastern side of the Delaware River sharing land boundaries with New Jersey. The state of Delaware, together with the Eastern Shore counties of Maryland and two counties of Virginia, form the Delmarva Peninsula, which stretches down the Mid-Atlantic Coast.

The definition of the northern boundary of the state is unusual. Most of the boundary between Delaware and Pennsylvania was originally defined by an arc extending 12 miles (19.3 km) from the cupola of the courthouse in the city of New Castle. This boundary is often referred to as the Twelve-Mile Circle. Although the Twelve-Mile Circle is often claimed to be the only territorial boundary in the U.S. that is a true arc, the Mexican boundary with Texas includes several arcs, and many cities in the South (such as Plains, Georgia) also have circular boundaries.

This border extends all the way east to the low-tide mark on the New Jersey shore, then continues south along the shoreline until it again reaches the 12-mile (19 km) arc in the south; then the boundary continues in a more conventional way in the middle of the main channel (thalweg) of the Delaware River.

To the west, a portion of the arc extends past the easternmost edge of Maryland. The remaining western border runs slightly east of due south from its intersection with the arc. The Wedge of land between the northwest part of the arc and the Maryland border was claimed by both Delaware and Pennsylvania until 1921, when Delaware's claim was confirmed.

Delaware is on a level plain, with the lowest mean elevation of any state in the nation. Its highest elevation, located at Ebright Azimuth, near Concord High School, is less than 450 feet (140 m) above sea level. The northernmost part of the state is part of the Piedmont Plateau with hills and rolling surfaces.

The Atlantic Seaboard fall line approximately follows the Robert Kirkwood Highway between Newark and Wilmington; south of this road is the Atlantic Coastal Plain with flat, sandy, and, in some parts, swampy ground. A ridge about 75 to 80 feet (23 to 24 m) high extends along the western boundary of the state and separates the watersheds that feed Delaware River and Bay to the east and the Chesapeake Bay to the west.

Since almost all of Delaware is a part of the Atlantic coastal plain, the effects of the ocean moderate its climate. The state lies in the humid subtropical climate (Köppen Cfa) zone. Despite its small size (roughly 100 miles (160 km) from its northernmost to southernmost points), there is significant variation in mean temperature and amount of snowfall between Sussex County and New Castle County. Moderated by the Atlantic Ocean and Delaware Bay, the southern portion of the state has a milder climate and a longer growing season than the northern portion of the state.

Summers are long, hot, and humid in Delaware, often with intense (but brief) late day thundershowers. Delaware averages 2,300 hrs of sunshine annually (higher than the USA average). Winters are modestly cool to cold in northern Delaware, and cool to mild in southern Delaware. The normal seasonal snowfall ranges from about 20.0 inches in Wilmington to only 10.0 inches in Lewes. In many winters no snow will fall in coastal Delaware. Northern Delaware falls into USDA Garden Zone 7a, while southern and coastal areas fall into USDA zone 7b and 8a. The milder climate in southern Delaware allows for subtropical flora such as the windmill palm, needle palm, and dwarf palmetto.

Delaware's all-time record high of 110 °F (43 °C) was recorded at Millsboro on July 21, 1930. The all-time record low of −17 °F (−27 °C) was also recorded at Millsboro, on January 17, 1893. The hardiness zones are 7B and 8A at the Delaware Beaches.

The transitional climate of Delaware supports a wide variety of vegetation. In the northern third of the state are found Northeastern coastal forests and mixed oak forests typical of the northeastern United States. In the southern two-thirds of the state are found Middle Atlantic coastal forests. Trap Pond State Park, along with areas in other parts of Sussex County, for example, support the northernmost stands of bald cypress trees in North America.

Delaware provides government subsidy support for the clean-up of property "lightly contaminated" by hazardous waste, the proceeds for which come from a tax on wholesale petroleum sales.

Wilmington is the state's most populous city (70,635) and its economic hub. It is located within commuting distance of both Philadelphia and Baltimore. Dover is the state capital and the second most populous city (38,079).

The table below lists the ten largest municipalities in the state based on the 2020 United States census.

The United States Census Bureau determined that the population of Delaware was 989,948 on April 1, 2020, an increase from the 2010 census figure of 897,934.

Delaware's history as a border state has led it to exhibit characteristics of both the Northern and the Southern regions of the United States. Generally, the rural Southern (or "Slower Lower") regions of Delaware below the Chesapeake and Delaware Canal embody a Southern culture, while densely-populated Northern Delaware above the canal—particularly Wilmington, a part of the Philadelphia metropolitan area—has more in common with that of the Northeast and the North. The U.S. Census Bureau designates Delaware as one of the South Atlantic States, but it is commonly associated with the Mid-Atlantic States or northeastern United States by other federal agencies, the media, and some residents.

Delaware is the sixth most densely populated state, with a population density of 442.6 people per square mile, 356.4 per square mile more than the national average, and ranking 45th in population. Delaware is one of five U.S. states (Maine, Vermont, West Virginia, Wyoming) that do not have a single city with a population over 100,000 as of the 2010 census. The center of population of Delaware is in New Castle County, in the town of Townsend.

According to HUD's 2022 Annual Homeless Assessment Report, there were an estimated 2,369 homeless people in Delaware.

According to the 2010 United States census, the racial composition of the state was 68.9% White American (65.3% Non-Hispanic White, 3.6% White Hispanic), 21.4% Black or African American, 0.5% American Indian and Alaska Native, 3.2% Asian American, 0.0% Native Hawaiian and other Pacific Islander, 3.4% some other race, and 2.7% of multiracial origin. People of Hispanic or Latino origin, of any race, made up 8.2% of the population.

The 2022 American Community Survey estimated the state had a racial and ethnic makeup of 60.6% non-Hispanic whites, 23.6% Black or African American, 0.7% American Indian or Alaska Native, 4.2% Asian, 0.1% Pacific Islander, 2.9% multiracial, and 10.1% Hispanic or Latin American of any race.

In the Native American community, the state has a Native American group, called in their own language Lenape, which was influential in the colonial period of the United States and is today headquartered in Cheswold, Kent County, Delaware. A band of the Nanticoke tribe of American Indians today resides in Sussex County and is headquartered in Millsboro, Sussex County, Delaware.

Delaware's population mainly consisted of people from the British Isles, African slaves, Germans and a few remaining Native Americans during the colonial era. Irish, Germans, Italians, Poles, and Russian Jewish immigrants were attracted by the industries in the Wilmington area. In the late 20th century a Puerto Rican community formed in Wilmington. Guatemalan people migrated to Sussex county to work in Delaware's poultry industry. A group of Native Americans in Delaware of mixed ethnicity, the Moors, live in Cheswold. The descendants of the Nanticoke people live around Millsboro. There is also a small numbers of Asians in New Castle county who work as scientific and engineering professionals.

The top countries of origin for Delaware's immigrants in 2018 were Mexico, India, Guatemala, China, and Jamaica.

Note: Births in table do not add up because Hispanics are counted both by their ethnicity and by their race, giving a higher overall number.

• Since 2016, data for births of White Hispanic origin are not collected, but included in one Hispanic group; persons of Hispanic origin may be of any race.

In 2000, 91% of Delaware residents of age 5 and older spoke only English at home; 5% spoke Spanish. French was the third most spoken language, used by 0.7% of the population, followed by Chinese (0.5%) and German (0.5%). Legislation has been proposed in both the House and the Senate in Delaware to designate English as the official language. Neither bill was passed in the legislature.

A 2012 Gallup poll found that Delaware's proportion of lesbian, gay, bisexual, and transgender adults stood at 3.4% of the population. This constitutes a total LGBT adult population estimate of 23,698 people. The number of same-sex couple households in 2010 stood at 2,646. This grew by 41.65% from a decade earlier. On July 1, 2013, same-sex marriage was legalized, and all civil unions were converted into marriages.

The predominant religion practiced in Delaware is Christianity. A 2014 estimate by the Pew Research Center found that members of Protestant churches accounted for almost half of the population, though the Roman Catholic Church was the largest single denomination in the state. By 2020, the Public Religion Research Institute determined 61% of the population was Christian. In 2022, the Public Religion Research Institute's survey revealed 60% were Christian, followed by Jews (3%), Hindus (1%), and New Agers (1%).

The Association of Religion Data Archives reported in 2010 that the three largest Christian denominational groups in Delaware by number of adherents are the Catholic Church at 182,532 adherents, the United Methodist Church with 53,656 members reported, and non-denominational evangelical Protestants, who numbered 22,973. In 2020, the Association of Religion Data Archives reported the largest Christian denominations were the Catholic Church with 197,094; non-denominational Protestants with 49,392, and United Methodists with 39,959.

The Roman Catholic Diocese of Wilmington and the Episcopal Diocese of Delaware oversee the parishes within their denominations. The A.U.M.P. Church, the oldest African-American denomination in the nation, was founded in Wilmington. It still has a substantial presence in the state. Reflecting new immigrant populations, an Islamic mosque has been built in the Ogletown area, and a Hindu temple in Hockessin.

Delaware is home to an Amish community which resides west of Dover in Kent County, consisting of nine church districts and about 1,650 people. The Amish first settled in Kent County in 1915. In recent years, increasing development has led to the decline in the number of Amish living in the community.

A 2012 survey of religious attitudes in the United States found that 34% of Delaware residents considered themselves "moderately religious", 33% "very religious", and 33% as "non-religious". At the 2014 Pew Research survey, 23% of the population were irreligious; the 2020 Public Religion Research Institute's survey determined 31% of the population were irreligious. In 2022, the same study showed 33% of the population as irreligious.

According to a 2020 study by Kiplinger, Delaware had the 17th most millionaires per capita in the United States; altogether, there were 25,937 such individuals. The median income for Delaware households as of 2020 was $64,805.

Delaware's agricultural output consists of poultry, nursery stock, soybeans, dairy products and corn.

As of October 2019, the state's unemployment rate was 3.7%.

The state's largest employers are:

• government (State of Delaware, New Castle County)
• education (University of Delaware, Delaware Technical Community College)
• banking (Bank of America, M&T Bank, JPMorgan Chase, Citigroup, Deutsche Bank)
• chemical, pharmaceutical, technology (DuPont de Nemours Inc., AstraZeneca, Syngenta, Agilent Technologies)
• healthcare (ChristianaCare (Christiana Hospital), Bayhealth Medical Center, Nemours Children's Hospital, Delaware)
• farming, specifically chicken farming in Sussex County (Perdue Farms, Mountaire Farms, Allen Family Foods)
• retail (Walmart, Walgreens, Acme Markets)

Since the mid-2000s, Delaware has seen the departure of the state's automotive manufacturing industry (General Motors Wilmington Assembly and Chrysler Newark Assembly), the corporate buyout of a major bank holding company (MBNA), the departure of the state's steel industry (Evraz Claymont Steel), the bankruptcy of a fiber mill (National Vulcanized Fiber), and the diminishing presence of AstraZeneca in Wilmington.

In late 2015, DuPont announced that 1,700 employees, nearly a third of its footprint in Delaware, would be laid off in early 2016. The merger of E.I. du Pont de Nemours & Co. and Dow Chemical Company into DowDuPont took place on September 1, 2017.

More than half of all U.S. publicly traded companies, and 63% of the Fortune 500, are incorporated in Delaware. The state's attractiveness as a corporate haven is largely because of its business-friendly corporation law. Franchise taxes on Delaware corporations supply about a fifth of the state's revenue. Although "USA (Delaware)" ranked as the world's most opaque jurisdiction on the Tax Justice Network's 2009 Financial Secrecy Index, the same group's 2011 Index ranks the U.S. fifth and does not specify Delaware. In Delaware, there are more than a million registered corporations, meaning there are more corporations than people.

Title 4, chapter 7 of the Delaware Code stipulates that alcoholic liquor be sold only in specifically licensed establishments, and only between 9:00 a.m. and 1:00 a.m. Until 2003, Delaware was among the several states enforcing blue laws and banned the sale of liquor on Sunday.

Two daily newspapers are based in Delaware, the Delaware State News, based in Dover and covering the two southern counties, and The News Journal covering Wilmington and northern Delaware. The state is also served by several weekly, monthly and online publications.

No standalone television stations are based solely in Delaware. The northern part of the state is served by network stations in Philadelphia and the southern part by network stations in Salisbury, Maryland. Philadelphia's ABC affiliate, WPVI-TV, maintains a news bureau in downtown Wilmington. Salisbury's CBS affiliate, WBOC-TV, maintains bureaus in Dover and Milton. Three Philadelphia-market stations—PBS member WHYY-TV, Ion affiliate WPPX, and MeTV affiliate WDPN-TV—all have Wilmington as their city of license, but maintain transmitters at the market antenna farm in Roxborough, Philadelphia and do not produce any Delaware-centric programming.

There are a numerous radio stations licensed in Delaware. WDDE 91.1 FM, WDEL 1150AM, WHGE-LP 95.3 FM, WILM 1450 AM, WVCW 99.5, WMPH 91.7 FM, WSTW 93.7 FM, WTMC 1380 AM and WWTX 1290AM are licensed from Wilmington. WRDX 92.9 FM is licensed from Smyrna. WDOV 1410AM, WDSD 94.7 FM and WRTX 91.7 FM are licensed from Dover.

Delaware is home to First State National Historical Park, a National Park Service unit composed of historic sites across the state including the New Castle Court House, Green, and Sheriff's House, Dover Green, Beaver Valley, Fort Christina, Old Swedes' Church, John Dickinson Plantation, and the Ryves Holt House. Delaware has several museums, wildlife refuges, parks, houses, lighthouses, and other historic places.

Rehoboth Beach, together with the towns of Lewes, Dewey Beach, Bethany Beach, South Bethany, and Fenwick Island, comprise Delaware's beach resorts. Rehoboth Beach often bills itself as "The Nation's Summer Capital" because it is a frequent summer vacation destination for Washington, D.C., residents as well as visitors from Maryland, Virginia, and in lesser numbers, Pennsylvania. Vacationers are drawn for many reasons, including the town's charm, artistic appeal, nightlife, and tax-free shopping. According to SeaGrant Delaware, the Delaware beaches generate $6.9 billion annually and over $711 million in tax revenue.

Delaware is home to several festivals, fairs, and events. Some of the more notable festivals are the Riverfest held in Seaford, the World Championship Punkin Chunkin formerly held at various locations throughout the state since 1986, the Rehoboth Beach Chocolate Festival, the Bethany Beach Jazz Funeral to mark the end of summer, the Apple Scrapple Festival held in Bridgeville, the Clifford Brown Jazz Festival in Wilmington, the Rehoboth Beach Jazz Festival, the Sea Witch Halloween Festival and Parade in Rehoboth Beach, the Rehoboth Beach Independent Film Festival, the Nanticoke Indian Pow Wow in Oak Orchard, Firefly Music Festival, and the Return Day Parade held after every election in Georgetown.

In 2015, tourism in Delaware generated $3.1 billion, which makes up five percent of the state's GDP. Delaware saw 8.5 million visitors in 2015, with the tourism industry employing 41,730 people, making it the 4th largest private employer in the state. Major origin markets for Delaware tourists include Philadelphia, Baltimore, New York City, Washington, D.C., and Harrisburg, with 97% of tourists arriving to the state by car and 75% of tourists coming from a distance of 200 miles (320 km) or less.

Delaware is also home to two large sporting venues. Dover Motor Speedway is a race track in Dover, and Frawley Stadium in Wilmington is the home of the Wilmington Blue Rocks, a Minor League Baseball team that is currently affiliated with the Washington Nationals.

In the early 1920s, Pierre S. du Pont served as president of the state board of education. At the time, state law prohibited money raised from white taxpayers from being used to support the state's schools for black children. Appalled by the condition of the black schools, du Pont donated four million dollars to construct 86 new school buildings.

Delaware was the origin of Belton v. Gebhart (1952), one of the four cases which were combined into Brown v. Board of Education, the Supreme Court of the United States decision that led to the end of officially segregated public schools. Significantly, Belton was the only case in which the state court found for the plaintiffs, thereby ruling that segregation is unconstitutional.

Unlike many states, Delaware's educational system is centralized in a state Superintendent of Education, with local school boards retaining control over taxation and some curriculum decisions. This centralized system, combined with the small size of the state, likely contributed to Delaware becoming the first state, after completion of a three-year, $30 million program ending in 1999, to wire every K-12 classroom in the state to the Internet.

As of 2011, the Delaware Department of Education had authorized the founding of 25 charter schools in the state, one of them being all-girls.

All teachers in the State's public school districts are unionized. As of January 2012, none of the State's charter schools are members of a teachers union. One of the State's teachers' unions is Delaware State Education Association (DSEA).

• Delaware College of Art and Design
• Delaware State University
• Delaware Technical & Community College
• Goldey-Beacom College
• University of Delaware—Ranked 63rd in the U.S. and in top 201–250 in the world (Times Higher Education World University Rankings 2018)
• Widener University School of Law
• Wilmington University

The transportation system in Delaware is under the governance and supervision of the Delaware Department of Transportation (DelDOT). Funding for DelDOT projects is drawn, in part, from the Delaware Transportation Trust Fund, established in 1987 to help stabilize transportation funding; the availability of the Trust led to a gradual separation of DelDOT operations from other Delaware state operations. DelDOT manages programs such as a Delaware Adopt-a-Highway program, major road route snow removal, traffic control infrastructure (signs and signals), toll road management, Delaware Division of Motor Vehicles, the Delaware Transit Corporation (branded as "DART First State", the state government public transportation organization), and others.

In 2009, DelDOT maintained 13,507 lane-miles, totaling 89 percent of the state's public roadway system, the rest being under the supervision of individual municipalities. This far exceeds the national average (20 percent) for state department of transportation maintenance responsibility.

One major branch of the U.S. Interstate Highway System, Interstate 95 (I-95), crosses Delaware southwest-to-northeast across New Castle County. Two Auxiliary Interstate Highway routes are also located in the state. Interstate 495 (I-495) is an eastern bypass of Wilmington. Interstate 295 (I-295) is a bypass of Philadelphia which begins south of Wilmington. In addition to Interstate highways, there are six U.S. highways that serve Delaware: U.S. 9, U.S. 13, U.S. 40, U.S. 113, U.S. 202, and U.S. 301. There are also several state highways that cross the state of Delaware; a few of them include DE 1, DE 9, and DE 404. U.S. 13 and DE 1 are primary north–south highways connecting Wilmington and Pennsylvania with Maryland, with DE 1 serving as the main route between Wilmington and the Delaware beaches. DE 9 is a north–south highway connecting Dover and Wilmington via a scenic route along the Delaware Bay. U.S. 40 is a primary east–west route, connecting Maryland with New Jersey. DE 404 is another primary east–west highway connecting the Chesapeake Bay Bridge in Maryland with the Delaware beaches. The state also operates three toll highways, the Delaware Turnpike, which is I-95, between Maryland and New Castle; the Korean War Veterans Memorial Highway, which is DE 1, between Wilmington and Dover; and the U.S. 301 toll road between the Maryland border and DE 1 in New Castle County.

A bicycle route, Delaware Bicycle Route 1, spans the north–south length of the state from the Maryland border in Fenwick Island to the Pennsylvania border north of Montchanin. It is the first of several signed bike routes planned in Delaware.

Delaware has about 875 bridges, 95 percent of which are under the supervision of DelDOT. About 30 percent of all Delaware bridges were built before 1950, and about 60 percent of the number are included in the National Bridge Inventory. Some bridges not under DelDOT supervision includes the four bridges on the Chesapeake and Delaware Canal, which are under the jurisdiction of the U.S. Army Corps of Engineers, and the Delaware Memorial Bridge, which is under the bi-state Delaware River and Bay Authority.

It has been noted that the tar and chip composition of secondary roads in Sussex County makes them more prone to deterioration than are the asphalt roadways in almost the rest of the state. Among these roads, Sussex (county road) 236 is among the most problematic.

Three ferries operate in the state of Delaware:

• Cape May–Lewes Ferry crosses the mouth of Delaware Bay between Lewes, Delaware and Cape May, New Jersey.
• Woodland Ferry (a cable ferry) crosses the Nanticoke River southwest of Seaford.
• Forts Ferry Crossing connects Delaware City with Fort Delaware and Fort Mott, New Jersey.

Amtrak has two stations in Delaware along the Northeast Corridor; the relatively quiet Newark Rail Station in Newark, and the busier Wilmington Station in Wilmington. The Northeast Corridor is also served by SEPTA's Wilmington/Newark Line, part of SEPTA Regional Rail, which serves Claymont, Wilmington, Churchmans Crossing, and Newark.

Two Class I railroads, Norfolk Southern and CSX, provide freight rail service in northern New Castle County. Norfolk Southern provides freight service along the Northeast Corridor and to industrial areas in Edgemoor, New Castle, and Delaware City. CSX's Philadelphia Subdivision passes through northern New Castle County parallel to the Amtrak Northeast Corridor. Multiple short-line railroads provide freight service in Delaware. The Delmarva Central Railroad operates the most trackage of the short-line railroads, running from an interchange with Norfolk Southern in Porter south through Dover, Harrington, and Seaford to Delmar, with another line running from Harrington to Frankford and branches from Ellendale to Milton and from Georgetown to Gravel Hill. The Delmarva Central Railroad connects with the Maryland and Delaware Railroad, which serves local customers in Sussex County. CSX connects with the freight/heritage operation, the Wilmington and Western Railroad, based in Wilmington and the East Penn Railroad, which operates a line from Wilmington to Coatesville, Pennsylvania.

The last north–south passenger trains through the main part of Delaware was the Pennsylvania Railroad's local Wilmington-Delmar train in 1965. This was a successor to the Del-Mar-Va Express and Cavalier, which had run from Philadelphia through the state's interior, to the end of the Delmarva Peninsula until the mid-1950s.

The DART First State public transportation system was named "Most Outstanding Public Transportation System" in 2003 by the American Public Transportation Association. Coverage of the system is broad within northern New Castle County with close association to major highways in Kent and Sussex counties. The system includes bus, subsidized passenger rail operated by Philadelphia transit agency SEPTA, and subsidized taxi and paratransit modes. The paratransit system, consisting of a statewide door-to-door bus service for the elderly and disabled, has been described by a Delaware state report as "the most generous paratransit system in the United States". As of 2012, fees for the paratransit service have not changed since 1988.

As of 2023, Delaware is served exclusively by Avelo Airlines out of Wilmington Airport, launching five routes to Florida on February 1. This put an end to an eight-month period during which Delaware had no scheduled air service, one of several since 1991. Various airlines had served Wilmington Airport, the latest departure being Frontier Airlines in June 2022.

Delaware is centrally situated in the Northeast megalopolis region of cities along I-95. Therefore, Delaware commercial airline passengers most frequently use Philadelphia International Airport (PHL), Baltimore-Washington International Thurgood Marshall Airport (BWI) and Washington Dulles International Airport (IAD) for domestic and international transit. Residents of Sussex County will also use Wicomico Regional Airport (SBY), as it is located less than 10 miles (16 km) from the Delaware border. Atlantic City International Airport (ACY), Newark Liberty International Airport (EWR), and Ronald Reagan Washington National Airport (DCA) are also within a 100-mile (160 km) radius of New Castle County.

Other general aviation airports in Delaware include Summit Airport near Middletown, Delaware Airpark near Cheswold, and Delaware Coastal Airport near Georgetown.

Dover Air Force Base, one of the largest in the country, is home to the 436th Airlift Wing and the 512th Airlift Wing. In addition to its other responsibilities in the Air Mobility Command, it serves as the entry point and mortuary for U.S. military personnel (and some civilians) who die overseas.

Delaware's fourth and current constitution, adopted in 1897, provides for executive, judicial and legislative branches.

The Delaware General Assembly consists of a House of Representatives with 41 members and a Senate with 21 members. It sits in Dover, the state capital. Representatives are elected to two-year terms, while senators are elected to four-year terms. The Senate confirms judicial and other nominees appointed by the governor.

Delaware's U.S. Senators are Tom Carper (Democrat) and Chris Coons (Democrat). Delaware's single U.S. Representative is Lisa Blunt Rochester (Democrat).

The Delaware Constitution establishes a number of courts:

• The Delaware Supreme Court is the state's highest court.
• The Delaware Superior Court is the state's trial court of general jurisdiction.
• The Delaware Court of Chancery deals primarily in corporate disputes.
• The Family Court handles domestic and custody matters.
• The Delaware Court of Common Pleas has jurisdiction over a limited class of civil and criminal matters.

Minor non-constitutional courts include the Justice of the Peace Courts and Aldermen's Courts.

Significantly, Delaware has one of the few remaining Courts of Chancery in the nation, which has jurisdiction over equity cases, the vast majority of which are corporate disputes, many relating to mergers and acquisitions. The Court of Chancery and the Delaware Supreme Court have developed a worldwide reputation for rendering concise opinions concerning corporate law which generally (but not always) grant broad discretion to corporate boards of directors and officers. In addition, the Delaware General Corporation Law, which forms the basis of the Courts' opinions, is widely regarded as giving great flexibility to corporations to manage their affairs. For these reasons, Delaware is considered to have the most business-friendly legal system in the United States; therefore a great number of companies are incorporated in Delaware, including 60% of the companies listed on the New York Stock Exchange.

Delaware was the last U.S. state to use judicial corporal punishment, in 1952.

The executive branch is headed by the Governor of Delaware. The current governor is John Carney (Democrat), who took office January 17, 2017. The lieutenant governor is Bethany Hall-Long. The governor presents a "State of the State" speech to a joint session of the Delaware legislature annually.

The executive branch also consists of the Attorney General of Delaware currently held by Kathy Jennings, the State Treasurer currently held by Colleen Davis, the Auditor of Accounts currently held by Lydia York and the Insurance Commissioner currently held by Trinidad Navarro.

Delaware is subdivided into three counties; from north to south they are New Castle, Kent and Sussex. This is the fewest among all states. Each county elects its own legislative body (known in New Castle and Sussex counties as County Council, and in Kent County as Levy Court), which deal primarily in zoning and development issues. Most functions which are handled on a county-by-county basis in other states—such as court and law enforcement—have been centralized in Delaware, leading to a significant concentration of power in the Delaware state government. The counties were historically divided into hundreds, which were used as tax reporting and voting districts until the 1960s, but now serve no administrative role, their only current official legal use being in real estate title descriptions.

The Democratic Party holds a plurality of registrations in Delaware. Currently, Democrats hold all positions of authority in Delaware, as well as majorities in the state Senate and House. The Democrats have held the governorship since 1993, having won the last seven gubernatorial elections. Democrats presently hold all the nine statewide elected offices, while the Republicans last won any statewide offices in 2014, State Auditor and State Treasurer.

During the First and Second Party Systems, Delaware was a stronghold for the Federalist and Whig Parties, respectively. After a relatively brief adherence to the Democratic Solid South following the US Civil War, Delaware became a Republican-leaning state from 1896 through 1948, voting for losing Republicans Charles Evans Hughes in 1916, Herbert Hoover in 1932, and Thomas Dewey in 1948.

During the second half of the 20th century, Delaware was a bellwether state, voting for the winner of every presidential election from 1952 through 1996. Delaware's bellwether status came to an end when Delaware voted for Al Gore in 2000 by 13%. Subsequent elections have continued to demonstrate Delaware's current strong Democratic lean: John Kerry carried the First State by 8% in 2004; Barack Obama carried it by 25% and by 19% in his two elections of 2008 and 2012; and Hillary Clinton carried it by 11% as she lost the Electoral College in 2016. In 2020, Delaware native (and Barack Obama's former vice president and running mate) Joe Biden headed the Democratic ticket; he carried his home state by just shy of 19% en route to a national 4.5% win.

The dominant factor in Delaware's political shift has been the strong Democratic trend in heavily urbanized New Castle County, home to 55% of Delaware's population. New Castle County has not voted Republican in a presidential election since 1988, and has given Democrats over 60% of its vote in every election from 2004 on. In 1992, 2000, 2004, and 2016, the Republican presidential candidate carried both Kent and Sussex but lost by double digits each time in New Castle County, which was a large enough margin to tip the state to the Democrats. New Castle County also elects a substantial majority of the state legislature; 27 of the 41 state house districts and 14 of the 21 state senate districts are based in New Castle County.

In a 2020 study, Delaware was ranked as the 18th hardest state for citizens to vote in.

Each of the 50 states of the United States has passed some form of freedom of information legislation, which provides a mechanism for the general public to request information of the government. In 2011 Delaware passed legislation placing a 15 business day time limit on addressing freedom-of-information requests, to either produce information or an explanation of why such information would take longer than this time to produce. A bill aimed at restricting Freedom of Information Act requests, Senate Bill 155, was discussed in committee.

Tax is collected by the Delaware Division of Revenue.

Delaware has six different income tax brackets, ranging from 2.2% to 5.95%. The state does not assess sales tax on consumers. The state does, however, impose a tax on the gross receipts of most businesses. Business and occupational license tax rates range from 0.096% to 1.92%, depending on the category of business activity.

Delaware does not assess a state-level tax on real or personal property. Real estate is subject to county property taxes, school district property taxes, vocational school district taxes, and, if located within an incorporated area, municipal property taxes.

Gambling provides significant revenue to the state. For instance, the casino at Delaware Park Racetrack provided more than $100 million to the state in 2010.

In June 2018, Delaware became the first U.S. state to legalize sports betting following the Supreme Court ruling to overturn the Professional and Amateur Sports Protection Act of 1992 (PASPA).

Professional teams

As Delaware has no franchises in the major American professional sports leagues, many Delawareans follow either Philadelphia or Baltimore teams. In the WNBA, the Washington Mystics enjoy a major following due to the presence of Wilmington native and University of Delaware product Elena Delle Donne. The University of Delaware's football team has a large following throughout the state, with the Delaware State University and Wesley College teams also enjoying a smaller degree of support.

Delaware is home to Dover Motor Speedway and Bally's Dover. Dover Motor Speedway, also known as the Monster Mile, is one of only 10 tracks in the nation to have hosted 100 or more NASCAR Cup Series races. Bally's Dover is a popular harness racing facility. It is the only co-located horse- and car-racing facility in the nation, with the Bally's Dover track located inside the Dover Motor Speedway track.

Delaware is represented in rugby by the Delaware Black Foxes, a 2015 expansion club.

Delaware has been home to professional wrestling outfit Combat Zone Wrestling (CZW). CZW has been affiliated with the annual Tournament of Death and ECWA with its annual Super 8 Tournament.

Delaware's official state sport is bicycling.

Delaware has had a foreign sister state in Japan, named Miyagi Prefecture. These two have shared relations since 1997, and have had exchange programs available for students that were briefly paused in wake of the earthquake and the tsunami that ensued in the prefecture during March 2011.

Prominent Delawareans include the du Pont family of politicians and businesspersons, and the 46th and current president of the United States Joe Biden, whose family moved to Delaware during his childhood, and who later represented Delaware for 36 years in the United States Senate before becoming the 47th vice president of the United States.

• Index of Delaware-related articles
• Outline of Delaware
• Delaware portal
• United States portal

• Kolchin, Peter (1994), American Slavery: 1619–1877, New York: Hill & Wang

• Delaware State Guide, Library of Congress

• State of Delaware (official website)
• Geographic data related to Delaware at OpenStreetMap
• Delaware Tourism homepage
• Delaware Map Data
• Energy & Environmental Data for Delaware
• USGS real-time, geographic, and other scientific resources of Delaware
• U.S. Census Bureau
• Delaware State Facts from USDA
• 2000 Census of Population and Housing for Delaware, U.S. Census Bureau
• Delaware at Ballotpedia
• Delaware at Curlie
• Delaware State Databases—Annotated list of searchable databases produced by Delaware state agencies and compiled by the Government Documents Roundtable of the American Library Association

The Delaware River is a major river in the Mid-Atlantic region of the United States and is the longest free-flowing (undammed) river in the Eastern United States. From the meeting of its branches in Hancock, New York, the river flows for 282 miles (454 km) along the borders of New York, Pennsylvania, New Jersey, and Delaware, before emptying into Delaware Bay.

The river has been recognized by the National Wildlife Federation as one of the country's Great Waters and has been called the "Lifeblood of the Northeast" by American Rivers. Its watershed drains an area of 13,539 square miles (35,070 km²) and provides drinking water for 17 million people, including half of New York City via the Delaware Aqueduct.

The Delaware River has two branches that rise in the Catskill Mountains of New York: the West Branch at Mount Jefferson in Jefferson, Schoharie County, and the East Branch at Grand Gorge, Delaware County. The branches merge to form the main Delaware River at Hancock, New York. Flowing south, the river remains relatively undeveloped, with 152 miles (245 km) protected as the Upper, Middle, and Lower Delaware National Scenic Rivers. At Trenton, New Jersey, the Delaware becomes tidal, navigable, and significantly more industrial. This section forms the backbone of the Delaware Valley metropolitan area, serving the port cities of Philadelphia, Camden, New Jersey, and Wilmington, Delaware. The river flows into Delaware Bay at Liston Point, 48 miles (77 km) upstream of the bay's outlet to the Atlantic Ocean between Cape May and Cape Henlopen.

Before the arrival of European settlers, the river was the homeland of the Lenape native people. They called the river Lenapewihittuk, or Lenape River, and Kithanne, meaning the largest river in this part of the country.

In 1609, the river was visited by a Dutch East India Company expedition led by Henry Hudson. Hudson, an English navigator, was hired to find a western route to Cathay (China), but his encounters set the stage for Dutch colonization of North America in the 17th century. Early Dutch and Swedish settlements were established along the lower section of the river and Delaware Bay. Both colonial powers called the river the South River (Zuidrivier), compared to the Hudson River, which was known as the North River. After the English expelled the Dutch and took control of the New Netherland colony in 1664, the river was renamed Delaware after Sir Thomas West, 3rd Baron De La Warr, an English nobleman and the Virginia colony's first royal governor, who defended the colony during the First Anglo-Powhatan War. George Washington's crossing of the Delaware River in 1776 led to the Americans winning the Battle of Trenton, which was a pivotal moment in the American Revolution.

The Delaware River is named in honor of Thomas West, 3rd Baron De La Warr (1577–1618), an English nobleman and the Virginia colony's first royal governor, who defended the colony during the First Anglo-Powhatan War. Lord de la Warr waged a punitive campaign to subdue the Powhatan after they had killed the colony's council president, John Ratcliffe, and attacked the colony's fledgling settlements. Lord de la Warr arrived with 150 soldiers in time to prevent the colony's original settlers at Jamestown from giving up and returning to England and is credited with saving the Virginia colony. The name of the barony (later an earldom) is pronounced as in the current spelling form "Delaware" ( DEL-ə-wair) and is thought to derive from French de la Guerre.

It has often been reported that the river and bay received the name "Delaware" after English forces under Richard Nicolls expelled the Dutch and took control of the New Netherland colony in 1664. However, the river and bay were known by the name Delaware as early as 1641. The state of Delaware was originally part of the William Penn's Pennsylvania colony. In 1682, the Duke of York granted Penn's request for access to the sea and leased him the territory along the western shore of Delaware Bay, which became known as the "Lower Counties on the Delaware". In 1704, the Lower Counties were given political autonomy to form a separate provincial assembly, but they shared Pennsylvania's provincial governor until the two colonies separated on June 15, 1776, and they remained separate as states after the establishment of the United States.

The name "Delaware" also came to be used as a collective name for the Lenape, a Native American people who inhabited an area of the basins of the Susquehanna River, Delaware River, and lower Hudson River in the northeastern United States at the time of European settlement, as well as for their language. As a result of disruption following the French and Indian War, American Revolutionary War, and the later Indian removals from the eastern United States, the name "Delaware" has been spread with the Lenape's diaspora to municipalities, counties and other geographical features in the American Midwest and Canada.

The Delaware River's drainage basin has an area of 13,539 square miles (35,070 km²) and encompasses 42 counties and 838 municipalities in five U.S. states: New York, New Jersey, Pennsylvania, Maryland, and Delaware.^: 9 This total area constitutes approximately 0.4% of the land mass in the United States.^: 9 In 2001, the watershed was 18% agricultural land, 14% developed land, and 68% forested land.^: vi

There are 216 tributary streams and creeks comprising an estimated 14,057 miles of streams and creeks, in the watershed.^{: p.11, 25} While the watershed is home to 4.17 million people according to the 2000 Federal Census, these bodies of water provide drinking water to 17 million people—roughly 6% of the population of the United States.^: vi, 9 The waters of the Delaware River's basin are used to sustain "fishing, transportation, power, cooling, recreation, and other industrial and residential purposes."^: 9 It is the 33rd largest river in the United States in terms of flow, but is among the nation's most heavily used rivers in daily freight tonnage.^: p.11 The average annual flow rate of the Delaware is 11,700 cubic feet per second at Trenton, New Jersey.^: 9 With no dams or impediments on the river's main stem, the Delaware is one of the few remaining large free-flowing rivers in the United States.^: 11

The West Branch of the Delaware River, also called the Mohawk Branch, spans approximately 90 miles (140 km) from the northern Catskill Mountains to its confluence with the Delaware River's East Branch at Hancock, New York. The last 6 miles (9.7 km) forms part of the boundary between New York and Pennsylvania.

The West Branch rises in Schoharie County, New York at 1,886 feet (575 m) above sea level, near Mount Jefferson, and flows tortuously through the plateau in a deep trough. The branch flows generally southwest, entering Delaware County and flowing through the towns of Stamford and Delhi. In southwestern Delaware County it flows in an increasingly winding course through the mountains, generally southwest. At Stilesville the West Branch was impounded in the 1960s to form the Cannonsville Reservoir, the westernmost of the reservoirs in the New York City water system. It is the most recently constructed New York City reservoir and began serving the city in 1964. Draining a large watershed of 455 square miles (1,180 km²), the reservoir's capacity is 95.7 billion US gallons (362,000,000 m³). This water flows over halfway through the reservoir to enter the 44-mile (71 km) West Delaware Tunnel in Tompkins, New York. Then it flows through the aqueduct into the Rondout Reservoir, where the water enters the 85 miles (137 km) Delaware Aqueduct, that contributes to roughly 50% of the city's drinking water supply. At Deposit, on the border between Broome and Delaware counties, it turns sharply to the southeast and is paralleled by New York State Route 17. It joins the East Branch at 880 feet (270 m) above sea level at Hancock to form the Delaware.

Similarly, the East Branch begins from a small pond south of Grand Gorge in the town of Roxbury in Delaware County, flowing southwest toward its impoundment by New York City to create the Pepacton Reservoir, the largest reservoir in the New York City water supply system. Its tributaries are the Beaver Kill River and the Willowemoc Creek which enter into the river ten miles (16 km) before the West Branch meets the East Branch. The confluence of the two branches is just south of Hancock.

The East Branch and West Branch of the Delaware River parallel each other, both flowing in a southwesterly direction.

From Hancock, New York, the Delaware flows between the northern Poconos in Pennsylvania, and the lowered shale beds north of the Catskills. The river flows down a broad Appalachian valley, passing Hawk's Nest overlook on the Upper Delaware Scenic Byway. The river flows southeast for 78 miles through rural regions along the New York-Pennsylvania border to Port Jervis and Shawangunk Ridge.

At Port Jervis, New York, it enters the Port Jervis trough. At this point, the Walpack Ridge deflects the Delaware into the Minisink Valley, where it follows the southwest strike of the eroded Marcellus Formation beds along the Pennsylvania–New Jersey state line for 25 miles (40 km) to the end of the ridge at Walpack Bend in the Delaware Water Gap National Recreation Area.The Minisink is a buried valley where the Delaware flows in a bed of glacial till that buried the eroded bedrock during the last glacial period. It then skirts the Kittatinny ridge, which it crosses at the Delaware Water Gap, between nearly vertical walls of sandstone, quartzite, and conglomerate, and then passes through a quiet and charming country of farm and forest, diversified with plateaus and escarpments, until it crosses the Appalachian plain and enters the hills again at Easton, Pennsylvania. From this point it is flanked at intervals by fine hills, and in places by cliffs, of which the finest are the Nockamixon Cliffs, 3 miles (5 km) long and above 200 feet (61 m) high.

The Appalachian Trail, which traverses the ridge of Kittatinny Mountain in New Jersey, and Blue Mountain in Pennsylvania, crosses the Delaware River at the Delaware Water Gap near Columbia, New Jersey.

In Easton, Pennsylvania, the Lehigh River joins the Delaware. At Trenton, the Delaware crosses the Atlantic Seaboard Fall Line with a drop of 8 feet (2.4 m).

Below Trenton, the Delaware flows between Philadelphia and New Jersey before becoming a broad, sluggish inlet of the sea, with many marshes along its side, widening steadily into its great estuary, Delaware Bay.

The Delaware River constitutes the boundary between Delaware and New Jersey. The Delaware-New Jersey border is actually at the easternmost river shoreline within the Twelve-Mile Circle of New Castle, rather than at mid-river, mid-channel or thalweg, so small portions of land lying west of the shoreline, but on the New Jersey side of the river, are pene-exclaves under the jurisdiction of Delaware. The rest of the borders follow a mid-channel approach.

At the time of the arrival of the Europeans in the early 17th century, the area near the Delaware River was inhabited by the Native American Lenape people. They called the Delaware River "Lenape Wihittuck", which means "the rapid stream of the Lenape". The Delaware River played a key factor in the economic and social development of the Mid-Atlantic region. In the seventeenth century it provided the conduit for colonial settlement by the Dutch (New Netherland) and the Swedish (New Sweden). Beginning in 1664, the region became an English possession as settlement by Quakers established the colonies of Pennsylvania (including present-day Delaware) and West Jersey. In the eighteenth century, cities like Philadelphia, Camden (then Cooper's Ferry), Trenton, Wilmington and New Castle were established upon the Delaware and their continued commercial success into the present day has been dependent on access to the river for trade and power. The river provided the path for the settlement of northeastern Pennsylvania's Lehigh Valley, and northwestern New Jersey by German Palatine immigrants—a population that became key in the agricultural development of the region.

The strategic Delaware River was the scene of several important campaigns during the American Revolutionary War. Perhaps the most famous event was George Washington's crossing of the Delaware River with the Continental Army on the night of December 25–26, 1776, leading to a successful surprise attack and victory against the Hessian troops occupying Trenton, New Jersey, on the morning of December 26.

During the Philadelphia Campaign control of the Delaware River was urgently needed by the British, allowing their naval fleet to supply troops occupying Philadelphia. To this end, the Battle of Red Bank and the Siege of Fort Mifflin were fought on and along the shores of the Delaware by the American and British navies, commanded by Commodore John Hazelwood and Admiral Francis Reynolds respectively. See historical map of that campaign.

The magnitude of the commerce of Philadelphia has made the improvements of the river below that port of great importance. Small improvements were attempted by Pennsylvania as early as 1771. Commerce was once important on the upper river, primarily prior to railway competition of 1857.

• The Delaware Division of the Pennsylvania Canal, running parallel with the river from Easton to Bristol, opened in 1830.
• The Delaware and Raritan Canal, which runs along the New Jersey side of the Delaware River from Bulls Island, New Jersey to Trenton, unites the waters of the Delaware and Raritan rivers as it empties the waters of the Delaware River via the canal outlet in New Brunswick. This canal water conduit is still used as a water supply source by the State of New Jersey.
• The Morris Canal (now abandoned and almost completely filled in) and the Delaware and Hudson Canal connected the Delaware and Hudson rivers.
• The Chesapeake and Delaware Canal joins the waters of the Delaware with those of the Chesapeake Bay.

The Delaware Water Gap National Recreation Area came about as a result of the failure of a controversial plan to build a dam on the Delaware River at Tocks Island, just north of the Delaware Water Gap to control water levels for flood control and hydroelectric power generation. The dam would have created a 37-mile (60 km) lake in the center of present park for use as a reservoir. Starting in 1960, the present-day area of the Recreation Area was acquired for the Army Corps of Engineers through eminent domain. Between 3,000 and 5,000 dwellings were demolished, including historical sites, and about 15,000 people were displaced by the project.

Because of massive environmental opposition, dwindling funds, and an unacceptable geological assessment of the dam's safety, the government transferred the property to the National Park Service in 1978. The National Park Service found itself as the caretaker of the previously endangered territory, and with the help of the federal government and surrounding communities, developed recreational facilities and worked to preserve the remaining historical structures.

The nearby Shawnee Inn, was identified in the 1990s as the only resort along the banks of the Delaware River.

American Rivers, an environmental advocacy group, named the Delaware River as the River of the Year for 2020, citing 75 years of progress in reducing pollution and restoring wildlife.

In 1984, the U.S. Department of the Treasury authorized the creation of a wine region or "American Viticultural Area" called the Central Delaware Valley AVA located in southeastern Pennsylvania and New Jersey. The wine appellation includes 96,000 acres (38,850 ha) surrounding the Delaware River north of Philadelphia and Trenton, New Jersey. In Pennsylvania, it consists of the territory along the Delaware River in Bucks County; in New Jersey, the AVA spans along the river in Hunterdon County and Mercer County from Titusville, New Jersey, just north of Trenton, northward to Musconetcong Mountain. As of 2013, there are no New Jersey wineries in the Central Delaware Valley AVA.

In the Project of 1885, the U.S. government undertook systematically the formation of a 26-foot (7.9 m) channel 600 feet (180 m) wide from Philadelphia to deep water in Delaware Bay. The River and Harbor Act of 1899 provided for a 30-foot (9.1 m) channel 600 feet (180 m) wide from Philadelphia to the deep water of the bay.

Since 1941, the Delaware River Main Channel was maintained at a depth of 40 ft (12 m). There is an effort underway to deepen the 102.5-mile stretch of this federal navigation channel, from Philadelphia and Camden to the mouth of the Delaware Bay to 45 feet.

The Delaware River port complex refers to the ports and energy facilities along the river in the tri-state PA-NJ-DE Delaware Valley region. They include the Port of Salem, the Port of Wilmington, the Port of Chester, the Port of Paulsboro, the Port of Philadelphia and the Port of Camden. Combined they create one of the largest shipping areas of the United States. In 2015, the ports of Philadelphia, Camden, and Wilmington handled 100 million tons of cargo from 2,243 ship arrivals, and supported 135,000 direct or indirect jobs. The biggest category of imports was fruit, carried by 490 ships, followed by petroleum, and containers, with 410 and 381 ships, respectively. The biggest category of exports was of shipping was containers, with 470 ships. In 2016, 2,427 ships arrived at Delaware River port facilities. Fruit ships were counted at 577, petroleum at 474, and containerized cargo at 431.

At one time it was a center for petroleum and chemical products and included facilities such as the Delaware City Refinery, the Dupont Chambers Works, Oceanport Terminal at Claymont, the Marcus Hook Refinery, the Trainer Refinery, the Paulsboro Asphalt Refinery, Paulsboro Refinery, Eagle Point Refinery, and Sunoco Fort Mifflin. As of 2011, crude oil was the largest single commodity transported on the Delaware River, accounting for half of all annual cargo tonnage.

The Delaware River is a major barrier to travel between New Jersey and Pennsylvania. Most of the larger bridges are tolled only westbound, and are owned by the Delaware River and Bay Authority, Delaware River Port Authority, Burlington County Bridge Commission or Delaware River Joint Toll Bridge Commission.

After New York City built 15 reservoirs to supply water to the city's growing population, it was unable to obtain permission to build an additional five reservoirs along the Delaware River's tributaries. As a result, in 1928 the city decided to draw water from the Delaware River, putting them in direct conflict with villages and towns across the river in Pennsylvania which were already using the Delaware for their water supply. The two sides eventually took their case to the U.S. Supreme Court, and in 1931, New York City was allowed to draw 440 million US gallons (1,700,000 m³) of water a day from the Delaware and its upstream tributaries.

The Delaware River has been attached to areas of high pollution. The Delaware River in 2012 was named the 5th most polluted river in the United States, explained by PennEnvironment and Environment New Jersey. The activist groups claim that there is about 7–10 million pounds of toxic chemicals flowing through the waterways due to dumping by DuPont Chambers Works. PennEnvironment also claims that the pollutants in the river can cause birth defects, infertility among women, and have been linked to cancer.

In 2015, the EPA saw the Delaware River as a concern for mass pollution especially in the Greater Philadelphia and Chester, Pennsylvania area. The EPA was involved after accusations that the river met standards made illegal by the Clean Water Act. In complying with the Clean Water Act, the EPA involved the Delaware County Regional Water Authority (DELCORA) where they set up a plan to spend around $200 million to help rid the waterway of about 740 million gallons of sewage and pollution. DELCORA was also fined about $1.4 million for allowing the Delaware River to have so much pollution residing in the river in the first place and for not complying with the Clean Water Act.

Part of the Clean Water Act explains how conditions of the river should be stable enough for human fishing and swimming. Even though the river has had success with the cleanup of pollution, the Delaware River still does not meet that standard of swimmable or fishable conditions in the Philadelphia/Chester region.

In March 2023, a pipe rupture at a Trinseo chemical plant in Bristol, Pennsylvania, released over 8,000 gallons of latex finishing material into the Otter Creek tributary, leading to a water advisory in Philadelphia.

With the failure of the dam project to come to fruition, the lack of flood control on the river left it vulnerable, and it has experienced a number of serious flooding events as the result of snow melt or rain run-off from heavy rainstorms. Record flooding occurred in August 1955, in the aftermath of the passing of the remnants of two separate hurricanes over the area within less than a week: first Hurricane Connie and then Hurricane Diane, which was, and still is, the wettest tropical cyclone to have hit the northeastern United States. The river gauge at Riegelsville, Pennsylvania recorded an all-time record crest of 38.85 feet (11.84 m) on August 19, 1955.

More recently, moderate to severe flooding has occurred along the river. The same gauge at Riegelsville recorded a peak of 30.95 feet (9.43 m) on September 23, 2004, 34.07 feet (10.38 m) on April 4, 2005, and 33.62 feet (10.25 m) on June 28, 2006, all considerably higher than the flood stage of 22 feet (6.7 m).

Since the upper Delaware basin has few population centers along its banks, flooding in this area mainly affects natural unpopulated flood plains. Residents in the middle part of the Delaware basin experience flooding, including three major floods in the three years (2004–2006) that have severely damaged their homes and land. The lower part of the Delaware basin from Philadelphia southward to the Delaware Bay is tidal and much wider than portions further north, and is not prone to river-related flooding (although tidal surges can cause minor flooding in this area).

The Delaware River Basin Commission, along with local governments, is working to try to address the issue of flooding along the river. As the past few years have seen a rise in catastrophic floods, most residents of the river basin feel that something must be done. The local governments have worked in association with FEMA to address many of these problems, however, due to insufficient federal funds, progress is slow.

A number of oil spills have taken place in the Delaware over the years.

• January 31, 1975: around 11,172,000 US gallons (42,290 m³) of crude oil spilled from the Corinthos tanker
• September 28, 1985: 435,000 US gallons (1,650 m³) of crude oil spilled from the Grand Eagle tanker after running aground on Marcus Hook Bar
• June 24, 1989: 306,000 US gallons (1,160 m³) of crude oil spilled from the Presidente Rivera tanker after running aground on Claymont Shoal
• November 26, 2004: 265,000 US gallons (1,000 m³) of crude oil spilled from the Athos 1 tanker; the tanker's hull had been punctured by a submerged, discarded anchor at the Port of Paulsboro. In 2020, the Supreme Court ruled that Citgo had failed to provide a safe berth for the vessel and was therefore jointly responsible for clean up costs. The company was ordered to pay $143 million.

The National Marine Fisheries Service is considering designating sixteen rivers as endangered habitat for the Atlantic sturgeon which would require more attention to be given to uses of the rivers that affect the fish.

The river is part of the National Wild and Scenic Rivers System.

• Foul Rift, rapids just south of Belvidere, New Jersey
• Geography of Pennsylvania
• List of municipalities on the Delaware River
• List of crossings of the Delaware River
• List of rivers of Delaware
• List of rivers of New Jersey
• List of rivers of New York
• List of rivers of Pennsylvania
• Partnership for the Delaware Estuary
• Upper Delaware Scenic and Recreational River

• Brooks, Victor (1999). How America Fought Its Wars. New York: Da Capo Press. ISBN 1-58097-002-8.
• Devastation on the Delaware: Stories and Images of the Deadly Flood of 1955 Archived May 14, 2021, at the Wayback Machine (2005, Word Forge Books Archived April 18, 2021, at the Wayback Machine, Ferndale, PA) The only comprehensive documentary of this weather disaster in the Delaware River Valley.
• Leach, Josiah Granville (1902). "Commodore John Hazlewood, Commander of the Pennsylvania Navy in the Revolution". The Pennsylvania Magazine of History and Biography. 26 (1). The Historical Society of Pennsylvania: 1–6. JSTOR 20086007.
• McGeorge, Wallace (1905). The Battle of Red Bank, Resulting in the Defeat of the Hessians and the Destruction of the British Frigate Augusta, Oct. 22 and 23, 1777. Camden, New Jersey: Sinnickson Chew, Printers.
• Savas, Theodore (2006). Guide to the Battles of the American Revolution. Savas Beatie. ISBN 1-932714-12-X.

• Delaware Riverkeeper Network
• Delaware River Basin Commission
• Delaware River Vessel Reporting System
• National Park Service: Delaware Water Gap National Recreation Area
• National Park Service: Upper Delaware Scenic & Recreational River
• National Park Service: Lower Delaware Wild & Scenic River
• U.S. Geological Survey: NJ stream gaging stations
• U.S. Geological Survey: NY stream gaging stations
• U.S. Geological Survey: PA stream gaging stations

• Marine Railway and Sectional Floating Dry Dock, Delaware River, Philadelphia, 1893 by D.J. Kennedy, Historical Society of Pennsylvania Archived November 19, 2012, at the Wayback Machine
• Winter on the River Delaware, 1856. Shows "U.S.S. Powhatan" by D.J. Kennedy, HSP Archived May 7, 2012, at the Wayback Machine
• "Map of the South River in New Netherland" from c. 1639 via the World Digital Library
• Socioeconomic Value of the Delaware River Basin in Delaware, New Jersey, New York, and Pennsylvania

• "Delaware, a river of the United States" . Collier's New Encyclopedia. 1921.
• "Delaware River" . The New Student's Reference Work . 1914.
• "Delaware. A river of the Eastern United States" . New International Encyclopedia. 1905.

Solar power in Delaware is small industry. Delaware had 150 MW of total installed capacity in 2020. The largest solar farms in the state included the 10 MW Dover Sun Park and the 12 MW Milford Solar Farm.

The expansion of Bruce A. Henry Solar Farm near Georgetown in Sussex County from 23 to 40 acres was completed in 2020.

Delaware ( DEL-ə-wair) is a state in the Mid-Atlantic region of the United States. It borders Maryland to its south and west, Pennsylvania to its north, New Jersey to its northeast, and the Atlantic Ocean to its east. The state's name derives from the adjacent Delaware Bay, which in turn was named after Thomas West, 3rd Baron De La Warr, an English nobleman and the Colony of Virginia's first colonial-era governor.

Delaware occupies the northeastern portion of the Delmarva Peninsula, and some islands and territory within the Delaware River. It is the 2nd smallest and 6th least populous state, but also the 6th most densely populated. Delaware's most populous city is Wilmington, and the state's capital is Dover, the 2nd most populous city in Delaware. The state is divided into three counties, the fewest number of counties of any of the 50 U.S. states; from north to south, the three counties are: New Castle County, Kent County, and Sussex County. The southern two counties, Kent and Sussex counties, historically have been predominantly agrarian economies. New Castle is more urbanized and is considered part of the Delaware Valley metropolitan statistical area that surrounds and includes Philadelphia, the nation's sixth most populous city. Delaware is considered part of the Southern United States by the U.S. Census Bureau, but the state's geography, culture, and history are a hybrid of the Mid-Atlantic and Northeastern regions of the country.

Before Delaware coastline was explored and developed by Europeans in the 16th century, the state was inhabited by several Native American tribes, including the Lenape in the north and Nanticoke in the south. The state was first colonized by Dutch traders at Zwaanendael, near present-day Lewes, Delaware, in 1631. Delaware was one of the Thirteen Colonies that participated in the American Revolution and American Revolutionary War, in which the American Continental Army, led by George Washington, defeated the British, ended British colonization and established the United States as a sovereign and independent nation. On December 7, 1787, Delaware was the first state to ratify the Constitution of the United States, earning it the nickname "The First State".