Managing guest comfort with restroom access

Although paper had been known as a wrapping and padding material in China since the 2nd century BC,^[7] a reference to the use of toilet paper dates back as early as c. 589 when the scholar-official Yan Zhitui (531–591) wrote:

Paper on which there are quotations or commentaries from the Five Classics or the names of sages, I dare not use for toilet purposes.^[6]

During the later Tang dynasty (618–907 AD), an Arab traveller to China in the year 851 AD remarked:

... they [the Chinese] do not wash themselves with water when they have done their necessities; but they only wipe themselves with paper.^[6]

During the early 14th century, it was recorded that in what is now Zhejiang alone, ten million packages of 1,000 to 10,000 sheets of toilet paper were manufactured annually.^[6] During the Ming dynasty (1368–1644 AD), it was recorded in 1393 that an annual supply of 720,000 sheets of toilet paper (approximately 2 by 3 ft (60 by 90 cm)) were produced for the general use of the imperial court at the capital of Nanjing.^[6] From the records of the Imperial Bureau of Supplies of that same year, it was also recorded that for the Hongwu Emperor's imperial family alone, there were 15,000 sheets of special soft-fabric toilet paper made, and each sheet of toilet paper was perfumed.^[6]

Elsewhere, wealthy people wiped themselves with wool, lace or hemp, while less wealthy people used their hand when defecating into rivers, or cleaned themselves with various materials such as rags, wood shavings, leaves, grass, hay, stones, pessoi, sand, moss, water, snow, ferns, plant husks, fruit skins, seashells, or corncobs, depending upon the country and weather conditions or social customs. In Ancient Rome, a sponge on a stick^[8] was commonly used, and, after use, placed back in a pail of vinegar. Several talmudic sources indicating ancient Jewish practice refer to the use of small pebbles, often carried in a special bag, and also to the use of dry grass and of the smooth edges of broken pottery jugs (e.g., Shabbat 81a, 82a, Yevamot 59b). These are all cited in the classic Biblical and Talmudic Medicine by the German physician Julius Preuss (Eng. trans. Sanhedrin Press, 1978).

The 16th-century French satirical writer François Rabelais, in Chapter XIII of Book 1 of his novel sequence Gargantua and Pantagruel, has his character Gargantua investigate a great number of ways of cleansing oneself after defecating. Gargantua dismisses the use of paper as ineffective, rhyming that: "Who his foul tail with paper wipes, Shall at his ballocks leave some chips." (Sir Thomas Urquhart's 1653 English translation). He concludes that "the neck of a goose, that is well downed" provides an optimum cleansing medium.^[9]

The rise of publishing by the eighteenth century led to the use of newspapers and cheap editions of popular books for cleansing. Lord Chesterfield, in a letter to his son in 1747, told of a man who purchased

a common edition of Horace, of which he tore off gradually a couple of pages, carried them with him to that necessary place, read them first, and then sent them down as a sacrifice to Cloacina; thus was so much time fairly gained...^[10]

In many parts of the world, especially where toilet paper or the necessary plumbing for disposal may be unavailable or unaffordable, toilet paper is not used. Also, in many parts of the world people consider using water a much cleaner and more sanitary practice than using paper.^[11] Cleansing is then performed with other methods or materials, such as water, for example using a bidet, a lota, rags, sand, leaves (including seaweed), corn cobs, animal furs, sticks or hands; afterwards, hands are washed with water and possibly soap.

Joseph Gayetty is widely credited with being the inventor of modern commercially available toilet paper in the United States. Gayetty's paper, first introduced in 1857, was available as late as the 1920s. Gayetty's Medicated Paper was sold in packages of flat sheets, watermarked with the inventor's name. Original advertisements for the product used the tagline "The greatest necessity of the age! Gayetty's medicated paper for the water-closet".

Seth Wheeler of Albany, New York, obtained the earliest United States patents for toilet paper and dispensers, the types of which eventually were in common use in that country, in 1883.^[12] Toilet paper dispensed from rolls was popularized when the Scott Paper Company began marketing it in 1890.^[13]

The manufacturing of this product had a long period of refinement, considering that as late as the 1930s, a selling point of the Northern Tissue company was that their toilet paper was "splinter free".^[14] The widespread adoption of the flush toilet increased the use of toilet paper, as heavier paper was more prone to clogging the trap that prevents sewer gases from escaping through the toilet.^[15]

Softer, two ply toilet roll was introduced in Britain in 1942, by St Andrew Mills in Walthamstow; this became the famous Andrex.^[16]

Moist toilet paper, called wet wipes, was first introduced in the United Kingdom by Andrex in the 1990s. It has been promoted as being a better method of cleaning than dry toilet paper after defecation, and may be useful for women during menstruation. It was promoted as a flushable product but it has been implicated in the creation of fatbergs; by 2016 some municipalities had begun education campaigns advising people not to flush used wet wipes.^[17]

More than seven billion rolls of toilet paper are sold yearly in the United States where an average of 23.6 rolls per capita per year is used.^[18]

External videos
Documentarian Brian Gersten's short film about the 1973 shortage, The Great Toilet Paper Scare

In 1973, Johnny Carson joked in his Tonight Show monologue about comments made by Wisconsin congressman Harold V. Froehlich about the possibility of a toilet paper shortage. Subsequently, consumers purchased abnormal amounts, causing an actual shortage in the United States for several months.^[19][20]

Toilet paper has been one of the commodities subject to shortages in Venezuela starting in the 2010s; the government seized one toilet paper factory in an effort to resolve the problem.^[21]

During the COVID-19 pandemic, toilet paper shortages were reported in March 2020 in multiple countries due to hoarding and panic buying.^{[22][23][24][25][26]} At first, few believed the pandemic would be serious. Later, people realized they might need to stock up on certain items in case of a shelter-in-place order, or in case they did not know how long such an order would last; suppliers could not assure that they could keep up with demand.^[27][28] However, manufacturers continued to produce even more than they had before. Demand was higher for the types of toilet paper used at home.^[29] In some countries the bidet was already seen as a solution, and a survey before the pandemic had indicated an increasing number of Americans would be interested.^[30] Amid the panic buying during the pandemic, the Australian toilet paper brand Quilton donated a million of toilet paper rolls to vulnerable Australians who were struggling due to the shortages of toilet paper.^[31]

• 
  Anal cleansing instruments known as chūgi from the Nara period (710 to 784) in Japan (The modern rolls in the background are for size comparison.)
• 
  A print by William Hogarth entitled A Just View of the British Stage from 1724 depicting Robert Wilks, Colley Cibber, and Barton Booth rehearsing a pantomime play with puppets enacting a prison break down a privy. The "play" is composed of nothing but toilet paper, and the scripts for Hamlet, inter al., are toilet paper.
• 
  A 1792 French Revolutionary caricature, depicting the French population using the Monarchist Brunswick Manifesto as toilet paper
• 
  Rolls of toilet paper, produced by Nokia in the 1960s, at the Vapriikki Museum Centre in Tampere, Finland
• 
  Le Troubadour (French) – 1960s package of toilet paper

Toilet paper is available in several types of paper, a variety of patterns, decorations, and textures, and it may be moistened or perfumed, although fragrances sometimes cause problems for users who are allergic to perfumes. The average measures of a modern roll of toilet paper is c. 10 cm (3 ⁠15/16⁠ in.) wide, and 12 cm (4

⁠23/32⁠ in.) in diameter, and weighs between 85 g (3.0 oz) and 196 g (6.9 oz).^[32] An alternative method of packing the sheets uses interleaved sheets in boxes, or in bulk for use in dispensers. "Hard" single-ply paper has been used as well as soft multi-ply.

The format of individual sheets of toilet paper, which is given by a perforation line, varies nationally. In Germany, Holland, France, Poland, Switzerland, for example, about postcard size is standard (about 100 × 140 mm), so about DIN format (DIN A6 105 × 148 mm). In England, the usual format is already somewhat wider, about 115 × 135 mm. The most extreme landscape format with 115 × 102 mm exists in Thailand. The most extreme portrait format (not counting toilet paper rolls without any perforation) is 100 × 366 mm; a promotional toilet paper from Schmidt Spiele in Germany.^[33] Manufactured toilet paper sheet in the United States was sized 4.5 in (110 mm) × 4 in (100 mm).^[34] Since 1999 the size of a sheet has been shrinking; Kimberly-Clark reduced the length of a sheet to 4.1 in (100 mm).^[35] Scott, in 2006, reduced the length of their product to 3.7 in (94 mm). The width of sheets was later reduced giving a general sheet size of 3.7 in (94 mm) long and 4.1 in (100 mm) wide. Larger sizes remain available.

The ply of a toilet paper refers to the number of layers per sheet. Rolls are typically available in single-ply, 2-ply, 3-ply, and 4-ply.

Phrases like "single roll", "double roll", "triple roll", "jumbo roll", and "mega roll" commonly used in retail advertising^[36] refer to the number of sheets per roll (though the actual number of sheets is also usually disclosed on packaging). A longer roll needs to be replaced less often, but the very largest sizes do not fit all toilet paper dispensers, especially in older homes.

Toilet paper is usually manufactured from pulpwood trees, but is also sometimes made from sugar cane byproducts or bamboo.

Toilet paper products vary greatly in the distinguishing technical factors, such as size, weight, roughness, softness, chemical residues, "finger-breakthrough" resistance, water-absorption, etc. The larger companies have very detailed, scientific market surveys to determine which marketing sectors require or demand which of the many technical qualities. Modern toilet paper may have a light coating of aloe or lotion or wax worked into the paper to reduce roughness.

Quality is usually determined by the number of plies (stacked sheets), coarseness, and durability. Low grade institutional toilet paper is typically of the lowest grade of paper, has only one or two plies, is very coarse and sometimes contains small amounts of embedded unbleached/unpulped paper; it was typically called "hard" toilet paper.^[37] A brand disinfected with carbolic acid was manufactured in Sheffield, United Kingdom under the Izal brand name by Newton Chambers until 1981.^[38] Mid-grade two ply is somewhat textured to provide some softness and is somewhat stronger. Premium toilet paper may have lotion and wax and has two to four plies of very finely pulped paper. If it is marketed as "luxury", it may be quilted or rippled (embossed), perfumed, colored or patterned, medicated (with anti-bacterial chemicals), or treated with aloe or other perfumes.

To advance decomposition of the paper in septic tanks or drainage, the paper used has shorter fibres than facial tissue or writing paper. The manufacturer tries to reach an optimal balance between rapid decomposition (which requires shorter fibres) and sturdiness (which requires longer fibres). Compaction of toilet paper in drain lines, such as in a clog, prevents fibre dispersion and largely halts the breakdown process.

A German quip says that the toilet paper of Nazi Germany was so rough and scratchy that it was almost unusable, so many people used old issues of the Völkischer Beobachter instead, because the paper was softer.^[39]

Colored toilet paper in colors such as pink, lavender, light blue, light green, purple, green, and light yellow (so that one could choose a color of toilet paper that matched or complemented the color of one's bathroom) was commonly sold in the United States from the 1960s. Up until 2004, Scott was one of the last remaining U.S. manufacturers to still produce toilet paper in beige, blue, and pink. However, the company has since cut production of colored paper altogether.^[40]

Colored toilet paper remains commonly available in some European countries. Here in solid color toilet paper base, apart from the natural tones between white and gray or beige, pastel shades prevail: pink, apricot, light yellow and light blue. In rare cases, pale purple or pale green can be found. However, rich colors are rarely used, such as black, wine red, neon green, royal blue. Flat printed toilet paper is uncommon. If there is printing, it is often one color. Common print colors are pink and pinkish red, also blue, more rarely purple, orange, brown or green.^[33]

Today, in the United States, plain unpatterned colored toilet paper has been mostly replaced by patterned toilet paper, normally white, with embossed decorative patterns or designs in various colors and different sizes depending on the brand. The patterns are in most cases "scatter patterns", that is, a motif is distributed ("scattered") several times (irregularly) over the surface. Stripes and dot patterns are rare. Occasionally, toilet papers have an embossed crocodile, wave, circle or check pattern. Some are additionally printed. Ornaments usually stand on their own as self-contained units. They never go uninterrupted (for example, as a border) from the first to the last sheet.^[33]

Predominant is everything that is associated "softness" and "fluffiness". There are decorations with bears, cats, rabbits, down feathers, clouds. Another motifs are things associated with "lightness": Clouds, downy feathers, leaves of all kinds, butterflies, flying birds. Another association is anything associated with pleasant fragrance: especially flowers of all kinds. Rare are motifs intended to appear noble, such as the Bourbon lily. Less rare are allusions to water, such as fish, shells and other aquatic creatures.^[33]

Toilet papers are also provided with texts (jokes, poems), joke motifs (banknotes, politicians in their own or neighbouring companies) or advertising imprints.

Toilet paper is offered in different qualities. The cheapest toilet papers have a texture close to crêpe paper. They are often made of recycled material. Expensive toilet papers are made from particularly absorbent, delicate tissue paper. Toilet paper usually has a smooth surface. With several intentions, it is occasionally embossed. On the one hand, the embossing can serve to stabilize the paper. Furthermore, wiping can become more effective. Thirdly, there are design reasons. In Switzerland, in particular, there are often toilet paper with burls. In Germany, the number of plies is considered a quality feature. In the USA, Great Britain and Japan, the quality feature is that the toilet paper is as delicate and fine as possible.^[33]

Some toilet papers are perfumed. Popular scents are chamomile, peach or rose. Other toilet papers are impregnated with antibacterial additives.

A toilet roll holder, also known as a toilet paper dispenser, is an item that holds a roll of toilet paper. There are at least seven types of holders:

1. A horizontal piece of wire mounted on a hinge, hanging from a door or wall.
2. A horizontal axle recessed in the wall.
3. A vertical axle recessed in the wall
4. A horizontal axle mounted on a freestanding frame.
5. A freestanding vertical pole on a base.
6. A wall mounted dispensing unit, usually containing more than one roll. This is used in the commercial/away-from-home marketplace.
7. A wall mounted dispensing unit with tissue interleaved in a "S"-type fold so the user can extract the tissue one sheet at a time.

Some commercial or institutional toilet paper is wrapped around a cylinder to many times the thickness of a standard toilet paper roll.

There are two choices of orientation when using a holder with a horizontal axle parallel to the wall: the toilet paper may hang over or under the roll. The choice is largely a matter of personal preference, dictated by habit. In surveys of American consumers and of bath and kitchen specialists, 60–70% of respondents prefer over. Most Americans think it should go over the top, like a waterfall.^[41]

Toilegami refers to toilet paper origami. Like table napkins, some fancy Japanese hotels fold the first squares of toilet paper on its dispenser to be presented in a fashionable way.^[42]

In the United States, toilet paper has been the primary tool in a prank known as "TP-ing" (pronounced "teepeeing"). TP-ing, or "toilet papering", is often favored by adolescents and is the act of throwing rolls of toilet paper over cars, trees, houses and gardens, causing the toilet paper to unfurl and cover the property, creating an inconvenient mess.^[43]

Children and cats may unroll an entire roll of toilet paper by spinning it until it completely unravels on the floor, or as a game by children wadding up one end, putting it in the toilet bowl without tearing it and then using the flushing of the toilet to pull new paper into the toilet, with the objective of flushing the entire roll down the toilet section at a time without the toilet paper breaking. Special toilet paper insert holders with an oblong shape were invented to prevent continuous unrolling without tearing to discourage this practice.^{[citation needed]}

Toilet paper pranks include talking toilet paper holders and inserts that are activated by the unrolling of the toilet paper and will loudly play an embarrassing message calling attention to the person defecating.^[44]

Other gags include custom toilet paper printed with jokes, stories or politician's images.^[45]

Alexander Balankin and coauthors have studied the behavior of toilet paper under tensile stress^[46][47] and during wetting and burning.^[48]

Toilet paper has been used in physics education to demonstrate the concepts of torque, moment of inertia, and angular momentum;^[49][50][51] and the conservation of momentum and energy.^[52]

One tree produces about 800 rolls (400 pounds (180 kg)) of toilet paper and about 83 million rolls are produced per day.^[53] Global toilet paper production consumes 27,000 trees daily.^[54]

More than seven billion rolls of toilet paper are sold yearly in the United States alone. Americans use an average of 141 rolls per capita a year which is equivalent to 12.7 kilograms (28 lb) of tissue paper per year.^[55] This figure is about 50% more than the average of other Western countries or Japan.^[56] The higher use in the United States may be explained by the fact that other countries people use bidets or spray hoses to clean themselves.^[57] Millions of trees are harvested in North and South America leaving ecological footprint concerns.^[58]

As of 2009^[update], between 22% and 48% of the toilet paper used in the United States comes from tree farms in the U.S. and South America, with the rest mostly coming from old, second growth forests, and, some from virgin forests.^[18]

Toilet paper made from recycled paper avoids the direct environmental impact of cutting down trees, and is commercially available. Recycled newspaper can contain BPA, an endocrine disruptor.^[59]

Toilet paper produced from bamboo is commercially available, and is in some ways more environmentally friendly than virgin pulpwood, because bamboo grows faster, taking less land and less water. For North American consumers, the Natural Resources Defense Council recommends recycled tree pulp over bamboo toilet paper, because tree forests promote more biodiversity and bamboo products must be shipped from Asia.^[60]

Toilet paper produced from bagasse, a byproduct of sugarcane, is commercially available, and avoids cutting down any plants because sugarcane is already grown for sugar production.^[59]

The most eco-friendly alternatives are to rely solely on soap and water for anal hygiene.^[60]

• Anal hygiene
• Fresh'n
• Xylospongium, an ancient equivalent

• De Beaumont, Sally; Tanner, Amoret; Rickards, Maurice (2000), Encyclopedia of Ephemera, UK: Routledge, pp. 190–191, ISBN 0-415-92648-3
• Knuth, Donald E. (October 1984), "The Toilet Paper Problem", The American Mathematical Monthly, 91 (8): 465–470, doi:10.2307/2322567, JSTOR 2322567
• Smyth, Richard (2012). Bum Fodder: An Absorbing History of Toilet Paper. Souvenir Press Limited. ISBN 978-0-285-64120-4.

Media related to Toilet paper at Wikimedia Commons

 

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Category Engineering portal

Infrastructure is the set of facilities and systems that serve a country, city, or other area,^[1] and encompasses the services and facilities necessary for its economy, households and firms to function.^[2] Infrastructure is composed of public and private physical structures such as roads, railways, bridges, airports, public transit systems, tunnels, water supply, sewers, electrical grids, and telecommunications (including Internet connectivity and broadband access). In general, infrastructure has been defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions" and maintain the surrounding environment.^[3]

Especially in light of the massive societal transformations needed to mitigate and adapt to climate change, contemporary infrastructure conversations frequently focus on sustainable development and green infrastructure. Acknowledging this importance, the international community has created policy focused on sustainable infrastructure through the Sustainable Development Goals, especially Sustainable Development Goal 9 "Industry, Innovation and Infrastructure".

One way to describe different types of infrastructure is to classify them as two distinct kinds: hard infrastructure and soft infrastructure.^[4] Hard infrastructure is the physical networks necessary for the functioning of a modern industrial society or industry.^[5] This includes roads, bridges, and railways. Soft infrastructure is all the institutions that maintain the economic, health, social, environmental, and cultural standards of a country.^[5] This includes educational programs, official statistics, parks and recreational facilities, law enforcement agencies, and emergency services.

A 1987 US National Research Council panel adopted the term "public works infrastructure", referring to:

"... both specific functional modes – highways, streets, roads, and bridges; mass transit; airports and airways; water supply and water resources; wastewater management; solid-waste treatment and disposal; electric power generation and transmission; telecommunications; and hazardous waste management – and the combined system these modal elements comprise. A comprehension of infrastructure spans not only these public works facilities, but also the operating procedures, management practices, and development policies that interact together with societal demand and the physical world to facilitate the transport of people and goods, provision of water for drinking and a variety of other uses, safe disposal of society's waste products, provision of energy where it is needed, and transmission of information within and between communities."^[6]

The American Society of Civil Engineers publishes an "Infrastructure Report Card" which represents the organization's opinion on the condition of various infrastructure every 2–4 years.^[7] As of 2017^[update] they grade 16 categories, namely aviation, bridges, dams, drinking water, energy, hazardous waste, inland waterways, levees, parks and recreation, ports, rail, roads, schools, solid waste, transit and wastewater.^{[7]: 4â€ÅÂ}  The United States has received a rating of "D+" on its infrastructure.^[8] This aging infrastructure is a result of governmental neglect and inadequate funding.^[8] As the United States presumably looks to upgrade its existing infrastructure, sustainable measures could be a consideration of the design, build, and operation plans.

Public infrastructure is that owned or available for use by the public (represented by the government).^[9] It includes:^[9]

• Transport infrastructure – vehicles, road, rail, cable and financing of transport
  • Aviation infrastructure – air traffic control technology in aviation
  • Rail transport – trackage, signals, electrification of rails
  • Road transport – roads, bridges, tunnels
• Critical infrastructure – assets required to sustain human life
• Energy infrastructure – transmission and storage of fossil fuels and renewable sources
• Information and communication infrastructure – systems of information storage and distribution
• Public capital – government-owned assets
• Public works – municipal infrastructure, maintenance functions and agencies
• Municipal solid waste – generation, collection, management of trash/garbage
• Sustainable urban infrastructure – technology, architecture, policy for sustainable living
• Water supply network – the distribution and maintenance of water supply
• Wastewater infrastructure – disposal and treatment of wastewater
• Infrastructure-based development

A way to embody personal infrastructure is to think of it in terms of human capital.^[10] Human capital is defined by the Encyclopædia Britannica as "intangible collective resources possessed by individuals and groups within a given population".^[11] The goal of personal infrastructure is to determine the quality of the economic agents' values. This results in three major tasks: the task of economic proxies in the economic process (teachers, unskilled and qualified labor, etc.); the importance of personal infrastructure for an individual (short and long-term consumption of education); and the social relevance of personal infrastructure.^[10] Essentially, personal infrastructure maps the human impact on infrastructure as it is related to the economy, individual growth, and social impact.

Institutional infrastructure branches from the term "economic constitution". According to Gianpiero Torrisi, institutional infrastructure is the object of economic and legal policy. It compromises the growth and sets norms.^[10] It refers to the degree of fair treatment of equal economic data and determines the framework within which economic agents may formulate their own economic plans and carry them out in co-operation with others.

Sustainable infrastructure refers to the processes of design and construction that take into consideration their environmental, economic, and social impact.^[8] Included in this section are several elements of sustainable schemes, including materials, water, energy, transportation, and waste management infrastructure.^[8] Although there are endless other factors of consideration, those will not be covered in this section.

Material infrastructure is defined as "those immobile, non-circulating capital goods that essentially contribute to the production of infrastructure goods and services needed to satisfy basic physical and social requirements of economic agents".^[10] There are two distinct qualities of material infrastructures: 1) fulfillment of social needs and 2) mass production. The first characteristic deals with the basic needs of human life. The second characteristic is the non-availability of infrastructure goods and services.^[10] Today, there are various materials that can be used to build infrastructure. The most prevalent ones are asphalt, concrete, steel, masonry, wood, polymers and composites.^[12]

According to the business dictionary, economic infrastructure can be defined as "internal facilities of a country that make business activity possible, such as communication, transportation and distribution networks, financial institutions and related international markets, and energy supply systems".^[13] Economic infrastructure support productive activities and events. This includes roads, highways, bridges, airports, cycling infrastructure, water distribution networks, sewer systems, and irrigation plants.^[10]

Social infrastructure can be broadly defined as the construction and maintenance of facilities that support social services.^[14] Social infrastructures are created to increase social comfort and promote economic activity. These include schools, parks and playgrounds, structures for public safety, waste disposal plants, hospitals, and sports areas.^[10]

Core assets provide essential services and have monopolistic characteristics.^[15] Investors seeking core infrastructure look for five different characteristics: income, low volatility of returns, diversification, inflation protection, and long-term liability matching.^[15] Core infrastructure incorporates all the main types of infrastructure, such as roads, highways, railways, public transportation, water, and gas supply.

Basic infrastructure refers to main railways, roads, canals, harbors and docks, the electromagnetic telegraph, drainage, dikes, and land reclamation.^[10] It consist of the more well-known and common features of infrastructure that we come across in our daily lives (buildings, roads, docks).

Complementary infrastructure refers to things like light railways, tramways, and gas/electricity/water supply.^[10] To complement something means to bring it to perfection or complete it. Complementary infrastructure deals with the little parts of the engineering world that make life more convenient and efficient. They are needed to ensure successful usage and marketing of an already finished product, like in the case of road bridges.^[16] Other examples are lights on sidewalks, landscaping around buildings, and benches where pedestrians can rest.

This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources in this section. Unsourced material may be challenged and removed. Find sources: "Infrastructure" – news · newspapers · books · scholar · JSTOR (August 2025) (Learn how and when to remove this message)

Engineers generally limit the term "infrastructure" to describe fixed assets that are in the form of a large network; in other words, hard infrastructure.^{[citation needed]} Efforts to devise more generic definitions of infrastructures have typically referred to the network aspects of most of the structures, and to the accumulated value of investments in the networks as assets.^{[citation needed]} One such definition from 1998 defined infrastructure as the network of assets "where the system as a whole is intended to be maintained indefinitely at a specified standard of service by the continuing replacement and refurbishment of its components".^[17]

Civil defense planners and developmental economists generally refer to both hard and soft infrastructure, including public services such as schools and hospitals, emergency services such as police and fire fighting, and basic services in the economic sector. The notion of infrastructure-based development combining long-term infrastructure investments by government agencies at central and regional levels with public private partnerships has proven popular among economists in Asia (notably Singapore and China), mainland Europe, and Latin America.

Military infrastructure is the buildings and permanent installations necessary for the support of military forces, whether they are stationed in bases, being deployed or engaged in operations. Examples include barracks, headquarters, airfields, communications facilities, stores of military equipment, port installations, and maintenance stations.^[18]

Communications infrastructure is the informal and formal channels of communication, political and social networks, or beliefs held by members of particular groups, as well as information technology, software development tools. Still underlying these more conceptual uses is the idea that infrastructure provides organizing structure and support for the system or organization it serves, whether it is a city, a nation, a corporation, or a collection of people with common interests. Examples include IT infrastructure, research infrastructure, terrorist infrastructure, employment infrastructure, and tourism infrastructure.^{[citation needed]}

The term "infrastructure" may be confused with the following overlapping or related concepts.

Land improvement and land development are general terms that in some contexts may include infrastructure, but in the context of a discussion of infrastructure would refer only to smaller-scale systems or works that are not included in infrastructure, because they are typically limited to a single parcel of land, and are owned and operated by the landowner. For example, an irrigation canal that serves a region or district would be included with infrastructure, but the private irrigation systems on individual land parcels would be considered land improvements, not infrastructure. Service connections to municipal service and public utility networks would also be considered land improvements, not infrastructure.^[19][20]

The term "public works" includes government-owned and operated infrastructure as well as public buildings, such as schools and courthouses. Public works generally refers to physical assets needed to deliver public services. Public services include both infrastructure and services generally provided by the government.

Infrastructure may be owned and managed by governments or by privately held companies, such as sole public utility or railway companies. Generally, most roads, major airports and other ports, water distribution systems, and sewage networks are publicly owned, whereas most energy and telecommunications networks are privately owned.^{[citation needed]} Publicly owned infrastructure may be paid for from taxes, tolls, or metered user fees, whereas private infrastructure is generally paid for by metered user fees.^[21][22] Major investment projects are generally financed by the issuance of long-term bonds.^{[citation needed]}

Government-owned and operated infrastructure may be developed and operated in the private sector or in public-private partnerships, in addition to in the public sector. As of 2008^[update] in the United States for example, public spending on infrastructure has varied between 2.3% and 3.6% of GDP since 1950.^[23] Many financial institutions invest in infrastructure.

According to researchers at the Overseas Development Institute, the lack of infrastructure in many developing countries represents one of the most significant limitations to economic growth and achievement of the Millennium Development Goals (MDGs). Infrastructure investments and maintenance can be very expensive, especially in such areas as landlocked, rural and sparsely populated countries in Africa. It has been argued that infrastructure investments contributed to more than half of Africa's improved growth performance between 1990 and 2005, and increased investment is necessary to maintain growth and tackle poverty. The returns to investment in infrastructure are very significant, with on average thirty to forty percent returns for telecommunications (ICT) investments, over forty percent for electricity generation, and eighty percent for roads.^[24]

The demand for infrastructure both by consumers and by companies is much higher than the amount invested.^[24] There are severe constraints on the supply side of the provision of infrastructure in Asia.^[25] The infrastructure financing gap between what is invested in Asia-Pacific (around US$48 billion) and what is needed (US$228 billion) is around US$180 billion every year.^[24]

In Latin America, three percent of GDP (around US$71 billion) would need to be invested in infrastructure in order to satisfy demand, yet in 2005, for example, only around two percent was invested leaving a financing gap of approximately US$24 billion.^[24]

In Africa, in order to reach the seven percent annual growth calculated to be required to meet the MDGs by 2015 would require infrastructure investments of about fifteen percent of GDP, or around US$93 billion a year. In fragile states, over thirty-seven percent of GDP would be required.^[24]

The source of financing for infrastructure varies significantly across sectors. Some sectors are dominated by government spending, others by overseas development aid (ODA), and yet others by private investors.^[24] In California, infrastructure financing districts are established by local governments to pay for physical facilities and services within a specified area by using property tax increases.^[26] In order to facilitate investment of the private sector in developing countries' infrastructure markets, it is necessary to design risk-allocation mechanisms more carefully, given the higher risks of their markets.^[27]

The spending money that comes from the government is less than it used to be. From the 1930s to 2019, the United States went from spending 4.2% of GDP to 2.5% of GDP on infrastructure.^[28] These under investments have accrued, in fact, according to the 2017 ASCE Infrastructure Report Card, from 2016 to 2025, infrastructure will be underinvested by $2 trillion.^[28] Compared to the global GDP percentages, The United States is tied for second-to-last place, with an average percentage of 2.4%. This means that the government spends less money on repairing old infrastructure and or on infrastructure as a whole.^[29]

In Sub-Saharan Africa, governments spend around US$9.4 billion out of a total of US$24.9 billion. In irrigation, governments represent almost all spending. In transport and energy a majority of investment is government spending. In ICT and water supply and sanitation, the private sector represents the majority of capital expenditure. Overall, between them aid, the private sector, and non-OECD financiers exceed government spending. The private sector spending alone equals state capital expenditure, though the majority is focused on ICT infrastructure investments. External financing increased in the 2000s (decade) and in Africa alone external infrastructure investments increased from US$7 billion in 2002 to US$27 billion in 2009. China, in particular, has emerged as an important investor.^[24]

The 2020 COVID-19 pandemic has only exacerbated the underfunding of infrastructure globally that has been accumulating for decades. The pandemic has increased unemployment and has widely disrupted the economy. This has serious impacts on households, businesses, and federal, state and local governments. This is especially detrimental to infrastructure because it is so dependent on funding from government agencies – with state and local governments accounting for approximately 75% of spending on public infrastructure in the United States.^[30]

Governments are facing enormous decreases in revenue, economic downturns, overworked health systems, and hesitant workforces, resulting in huge budget deficits across the board. However, they must also scale up public investment to ensure successful reopening, boost growth and employment, and green their economies.^[31] The unusually large scale of the packages needed for COVID-19 was accompanied by widespread calls for "greening" them to meet the dual goals of economic recovery and environmental sustainability.^[32] However, as of March 2021, only a small fraction of the G20 COVID-19 related fiscal measures was found to be climate friendly.^[32]

Although it is readily apparent that much effort is needed to repair the economic damage inflicted by the Coronavirus epidemic, an immediate return to business as usual could be environmentally harmful, as shown by the 2007-08 financial crisis in the United States. While the ensuing economic slowdown reduced global greenhouse gas emissions in 2009, emissions reached a record high in 2010, partially due to governments' implemented economic stimulus measures with minimal consideration of the environmental consequences.^[33] The concern is whether this same pattern will repeat itself. The post-COVID-19 period could determine whether the world meets or misses the emissions goals of the 2015 Paris Agreement and limits global warming to 1.5 degrees C to 2 degrees C.^[34]

As a result of the COVID-19 epidemic, a host of factors could jeopardize a low-carbon recovery plan: this includes reduced attention on the global political stage (2020 UN Climate Summit has been postponed to 2021), the relaxing of environmental regulations in pursuit of economic growth, decreased oil prices preventing low-carbon technologies from being competitive, and finally, stimulus programs that take away funds that could have been used to further the process of decarbonization.^[33] Research suggests that a recovery plan based on lower-carbon emissions could not only make significant emissions reductions needed to battle climate change, but also create more economic growth and jobs than a high-carbon recovery plan would.^[33] A study published in the Oxford Review of Economic Policy, more than 200 economists and economic officials reported that "green" economic-recovery initiatives performed at least as well as less "green" initiatives.^[35] There have also been calls for an independent body could provide a comparable assessment of countries' fiscal policies, promoting transparency and accountability at the international level.^[32]

In addition, in an econometric study published in the Economic Modelling journal, an analysis on government energy technology spending showed that spending on the renewable energy sector created five more jobs per million dollars invested than spending on fossil fuels.^[36] Since sustainable infrastructure is more beneficial in both an economic and environmental context, it represents the future of infrastructure. Especially with increasing pressure from climate change and diminishing natural resources, infrastructure not only needs to maintain economic development and job development, and a high quality of life for residents, but also protect the environment and its natural resources.^[31]

Sustainable energy infrastructure includes types of renewable energy power plants as well as the means of exchange from the plant to the homes and businesses that use that energy. Renewable energy includes well researched and widely implemented methods such as wind, solar, and hydraulic power, as well as newer and less commonly used types of power creation such as fusion energy. Sustainable energy infrastructure must maintain a strong supply relative to demand, and must also maintain sufficiently low prices for consumers so as not to decrease demand.^[8] Any type of renewable energy infrastructure that fails to meet these consumption and price requirements will ultimately be forced out of the market by prevailing non renewable energy sources.

Sustainable water infrastructure is focused on a community's sufficient access to clean, safe drinking water.^[8] Water is a public good along with electricity, which means that sustainable water catchment and distribution systems must remain affordable to all members of a population.^[8] "Sustainable Water" may refer to a nation or community's ability to be self-sustainable, with enough water to meet multiple needs including agriculture, industry, sanitation, and drinking water. It can also refer to the holistic and effective management of water resources.^[37] Increasingly, policy makers and regulators are incorporating Nature-based solutions (NBS or NbS) into attempts to achieve sustainable water infrastructure.

Sustainable waste management systems aim to minimize the amount of waste products produced by individuals and corporations.^[38] Commercial waste management plans have transitioned from simple waste removal plans into comprehensive plans focused on reducing the total amount of waste produced before removal.^[38] Sustainable waste management is beneficial environmentally, and can also cut costs for businesses that reduce their amount of disposed goods.^[38]

Sustainable transportation includes a shift away from private, greenhouse gas emitting cars in favor of adopting methods of transportation that are either carbon neutral or reduce carbon emissions such as bikes or electric bus systems.^[39] Additionally, cities must invest in the appropriate built environments for these ecologically preferable modes of transportation.^[39] Cities will need to invest in public transportation networks, as well as bike path networks among other sustainable solutions that incentivize citizens to use these alternate transit options. Reducing the urban dependency on cars is a fundamental goal of developing sustainable transportation, and this cannot be accomplished without a coordinated focus on both creating the methods of transportation themselves and providing them with networks that are equally or more efficient than existing car networks such as aging highway systems.^[39]

Another solution to transition into a more sustainable infrastructure is using more sustainable materials. A material is sustainable if the needed amount can be produced without depleting non-renewable resources.^[40] It also should have low environmental impacts by not disrupting the established steady-state equilibrium of it.^[40] The materials should also be resilient, renewable, reusable, and recyclable.^[41]

Today, concrete is one of the most common materials used in infrastructure. There is twice as much concrete used in construction than all other building materials combined.^[42] It is the backbone of industrialization, as it is used in bridges, piers, pipelines, pavements, and buildings.^[43] However, while they do serve as a connection between cities, transportation for people and goods, and protection for land against flooding and erosion, they only last for 50 to 100 years.^[44] Many were built within the last 50 years, which means many infrastructures need substantial maintenance to continue functioning.

However, concrete is not sustainable. The production of concrete contributes up to 8% of the world's greenhouse gas emissions.^[45] A tenth of the world's industrial water usage is from producing concrete.^[45] Even transporting the raw materials to concrete production sites adds to airborne pollution.^[45] Furthermore, the production sites and the infrastructures themselves all strip away agricultural land that could have been fertile soil or habitats vital to the ecosystem.

Green infrastructure is a type of sustainable infrastructure. Green infrastructure uses plant or soil systems to restore some of the natural processes needed to manage water, reduce the effects of disasters such as flooding,^[46] and create healthier urban environments.^[47] In a more practical sense, it refers to a decentralized network of stormwater management practices, which includes green roofs, trees, bioretention and infiltration, and permeable pavement.^[48] Green infrastructure has become an increasingly popular strategy in recent years due to its effectiveness in providing ecological, economic, and social benefits – including positively impacting energy consumption, air quality, and carbon reduction and sequestration.^[48]

A green roof is a rooftop that is partially or completely covered with growing vegetation planted over a membrane. It also includes additional layers, including a root barrier and drainage and irrigation systems.^[49] There are several categories of green roofs, including extensive (have a growing media depth ranging from two to six inches) and intensive (have a growing media with a depth greater than six inches).^[49] One benefit of green roofs is that they reduce stormwater runoff because of its ability to store water in its growing media, reducing the runoff entering the sewer system and waterways, which also decreases the risk of combined sewer overflows.^[49] They reduce energy usage since the growing media provides additional insulation, reduces the amount of solar radiation on the roof's surface, and provides evaporative cooling from water in the plants, which reduce the roof surface temperatures and heat influx.^[49] Green roofs also reduce atmospheric carbon dioxide since the vegetation sequesters carbon and, since they reduce energy usage and the urban heat island by reducing the roof temperature, they also lower carbon dioxide emissions from electricity generation.^[50]

Tree planting provides a host of ecological, social, and economic benefits. Trees can intercept rain, support infiltration and water storage in soil, diminish the impact of raindrops on barren surfaces, minimize soil moisture through transpiration, and they help reduce stormwater runoff.^[47] Additionally, trees contribute to recharging local aquifers and improve the health of watershed systems. Trees also reduce energy usage by providing shade and releasing water into the atmosphere which cools the air and reduces the amount of heat absorbed by buildings.^[48] Finally, trees improve air quality by absorbing harmful air pollutants reducing the amount of greenhouse gases.

There are a variety of types of bioretention and infiltration practices, including rain gardens and bioswales.^[48] A rain garden is planted in a small depression or natural slope and includes native shrubs and flowers. They temporarily hold and absorb rain water and are effective in removing up to 90% of nutrients and chemicals and up to 80% of sediments from the runoff.^[51] As a result, they soak 30% more water than conventional gardens.^[51] Bioswales are planted in paved areas like parking lots or sidewalks and are made to allow for overflow into the sewer system by trapping silt and other pollutants, which are normally left over from impermeable surfaces.^[48] Both rain gardens and bioswales mitigate flood impacts and prevent stormwater from polluting local waterways; increase the usable water supply by reducing the amount of water needed for outdoor irrigation; improve air quality by minimizing the amount of water going into treatment facilities, which also reduces energy usage and, as a result, reduces air pollution since less greenhouse gases are emitted.^[48]

Smart cities use innovative methods of design and implementation in various sectors of infrastructure and planning to create communities that operate at a higher level of relative sustainability than their traditional counterparts.^[8] In a sustainable city, urban resilience as well as infrastructure reliability must both be present.^[8] Urban resilience is defined by a city's capacity to quickly adapt or recover from infrastructure defects, and infrastructure reliability means that systems must work efficiently while continuing to maximize their output.^[8] When urban resilience and infrastructure reliability interact, cities are able to produce the same level of output at similarly reasonable costs as compared to other non sustainable communities, while still maintaining ease of operation and usage.

Masdar City is a proposed zero emission smart city that will be contracted in the United Arab Emirates.^[52] Some individuals have referred to this planned settlement as "utopia-like", due to the fact that it will feature multiple sustainable infrastructure elements, including energy, water, waste management, and transportation. Masdar City will have a power infrastructure containing renewable energy methods including solar energy.^[52]

Masdar City is located in a desert region, meaning that sustainable collection and distribution of water is dependent on the city's ability to use water at innovative stages of the water cycle.^[53] The city will use groundwater, greywater, seawater, blackwater, and other water resources to obtain both drinking and landscaping water.^[53]

Initially, Masdar City will be waste-free.^[52] Recycling and other waste management and waste reduction methods will be encouraged.^[52] Additionally, the city will implement a system to convert waste into fertilizer, which will decrease the amount of space needed for waste accumulation as well as provide an environmentally friendly alternative to traditional fertilizer production methods.

No cars will be allowed in Masdar City, contributing to low carbon emissions within the city boundaries.^[52] Instead, alternative transportation options will be prioritized during infrastructure development. This means that a bike lane network will be accessible and comprehensive, and other options will also be available.^[52]

• Koh, Jae Myong (2018) Green Infrastructure Financing: Institutional Investors, PPPs and Bankable Projects, London: Palgrave Macmillan. ISBN 978-3-319-71769-2.
• Nurre, Sarah G.; Cavdaroglu, Burak; Mitchell, John E.; Sharkey, Thomas C.; Wallace, William A. (December 2012). "Restoring infrastructure systems: An integrated network design and scheduling (INDS) problem". European Journal of Operational Research. 223 (3): 794–806. doi:10.1016/j.ejor.2012.07.010.
• Ascher, Kate (2007). The works: anatomy of a city. Researched by Wendy Marech (Reprint ed.). New York: Penguin Press. ISBN 978-0-14-311270-9.
• Larry W. Beeferman, "Pension Fund Investment in Infrastructure: A Resource Paper", Capital Matter (Occasional Paper Series), No. 3 December 2008
• A. Eberhard, "Infrastructure Regulation in Developing Countries", PPIAF Working Paper No. 4 (2007) World Bank
• M. Nicolas J. Firzli and Vincent Bazi, "Infrastructure Investments in an Age of Austerity: The Pension and Sovereign Funds Perspective", published jointly in Revue Analyse Financière, Q4 2011 issue, pp. 34–37 and USAK/JTW July 30, 2011 (online edition)
• Hayes, Brian (2005). Infrastructure: the book of everything for the industrial landscape (1st ed.). New York: Norton. ISBN 978-0-393-32959-9.
• Huler, Scott (2010). On the grid: a plot of land, an average neighborhood, and the systems that make our world work. Emmaus, PA: Rodale. ISBN 978-1-60529-647-0.
• Georg Inderst, "Pension Fund Investment in Infrastructure", OECD Working Papers on Insurance and Private Pensions, No. 32 (2009)
• Dalakoglou, Dimitris (2017). The Road: An Ethnography of (Im)mobility, space and cross-border infrastructures. Manchester: Manchester University Press/ Oxford university Press.

• Body of Knowledge on Infrastructure Regulation
• Next Generation Infrastructures international research programme
• Report Card on America's Infrastructure
• sustainable sports infrastructure
• Dirk van Laak: Infrastructures, version: 1.0, in: Docupedia Zeitgeschichte, 20th may 2021