Ocean Tides

 Editor’s Note:  Science (our religion) is mainly a cataloging of events and objects and assigning them a cause.  It uses the moon to explain the periodic bulging and surging of the ocean that we call tides.  This may be, but I believe someday we may discover that it is the tides that cause the moon.

Most of the information below is adapted from an interesting website called Keith’s Moon Page.–Hardly Waite.

The word “tides” is a generic term used to define the alternating rise and fall in sea level with respect to the land, produced by the gravitational attraction of the moon and the sun. To a much smaller extent, tides also occur in large lakes, the atmosphere, and within the solid crust of the earth, acted upon by these same gravitational forces of the moon and sun.
Tides are created because the Earth and the moon are attracted to each other, just like magnets are attracted to each other. The moon tries to pull at anything on the Earth to bring it closer. But, the Earth is able to hold onto everything except the water. Since the water is always moving, the Earth cannot hold onto it, and the moon is able to pull at it.

Each day, there are two high tides and two low tides. The ocean is constantly moving from high tide to low tide, and then back to high tide. There is a period of about 12 hours and 25 minutes between the two high tides.

When the moon is full or new, the gravitational pull of the moon and sun are combined. At these times, the high tides are very high and the low tides are very low. This is known as a spring high tide.

Spring Tides

Spring tides are especially strong tides (they do not have anything to do with the season Spring). They occur when the Earth, the Sun, and the Moon are in a line. The gravitational forces of the Moon and the Sun both contribute to the tides. Spring tides occur during the full moon and the new moon.

Neap Tides
During the moon’s quarter phases the sun and moon work at right angles, causing the bulges to cancel each other. The result is a smaller difference between high and low tides and is known as a neap tide. Neap tides are especially weak tides. They occur when the gravitational forces of the Moon and the Sun are perpendicular to one another (with respect to the Earth). Neap tides occur during quarter moons.

Winds and currents move the surface water causing waves. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon. Another bulge occurs on the opposite side, since the Earth is also being pulled toward the moon (and away from the water on the far side). Ocean levels fluctuate daily as the sun, moon and earth interact. As the moon travels around the earth and as they, together, travel around the sun, the combined gravitational forces cause the world’s oceans to rise and fall. Since the earth is rotating while this is happening, two tides occur each day. 

More About Tides

 

• The gravitational force of the moon is one ten-millionth that of earth, but when you combine other forces such as the earth’s centrifugal force created by its spin, you get tides.
• The sun’s gravitational force on the earth is only 46 percent that of the moon. Making the moon the single most important factor for the creation of tides.
• The sun’s gravity also produces tides. But since the forces are smaller, as compared to the moon, the effects are greatly decreased.
• Tides are not caused by the direct pull of the moon’s gravity. The moon is pulling upwards on the water while the earth is pulling downward. Slight advantage to the moon and thus we have tides.
• Whenever the Moon, Earth and Sun are aligned, the gravitational pull of the sun adds to that of the moon causing maximum tides.
• Spring tides happen when the sun and moon are on the same side of the earth (New Moon) or when the sun and moon are on opposite sides of the earth (Full Moon).
• When the Moon is at first quarter or last quarter phase (meaning that it is located at right angles to the Earth-Sun line), the Sun and Moon interfere with each other in producing tidal bulges and tides are generally weaker; these are called neap tides.
• Spring tides and neap tide levels are about 20% higher or lower than average.
• Offshore, in the deep ocean, the difference in tides is usually less than 1.6 feet
• The surf grows when it approaches a beach, and the tide increases. In bays and estuaries, this effect is amplified. (In the Bay of Fundy, tides have a range of 44.6 ft.)
• The highest tides in the world are at the Bay of Fundy in Nova Scotia, Canada.
• Because the earth rotates on its axis the moon completes one orbit in our sky every 25 hours (Not to be confused with moon’s 27 day orbit around the earth), we get two tidal peaks as well as two tidal troughs. These events are separated by about 12 hours.
• Since the moon moves around the Earth, it is not always in the same place at the same time each day. So, each day, the times for high and low tides change by 50 minutes.
• The type of gravitational force that causes tides is know as “Tractive” force.

Adapted from Keith’s Moon Page.

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 Egypt Believes that It Owns the Nile; Ethiopia Does Not Agree

 Editor’s Note: The following is excerpted from a Voice of America article. The dispute over Ethiopia’s dam on the Blue Nile is not new, but the tensions are festering.–Hardly Waite. 

A rift continued  between Egypt and Ethiopia over a plan by Addis Ababa to build a huge dam on one of the tributaries of the River Nile, while an announcement by South Sudan that it has chosen more than a dozen potential dam sites along the river evoked little concern from Nile Basin Initiative countries meeting in Juba.

Egypt, which under a colonial-era law controls the biggest share of the Nile’s waters, has been at loggerheads for months with Ethiopia over a plan by Addis Ababa to build a 6,000-megawatt dam with a 63 billion cubic meter reservoir on a tributary of the Nile. Cairo is worried that the dam would reduce the amount of water available in Egypt.

But Ethiopian’s Minister of Water, Alemayehu Tegenu, said his government is not ready to back off of its plans.

“The Nile is a common resource. The Nile is a gift to the population of the all Nile Basin Countries. We will not allow a single country to have full control of our shared resources. Conflicts and tensions over the utilization of the Nile are not helpful and will not lead to sustainable utilisation,” Tegenu said, adding that the new dam will help to solve power supply problems in Ethiopia.

Construction on the dam started two years ago on Ethiopia’s  Blue Nile River, whose basin accounts for about 75 percent of the water flowing into the lower Nile River.

Egypt’s Deputy Minister for Water Resources Ahmad Bah Eldein insisted his government does not want to deny any country the opportunity to make improvements, but said that Cairo would not overlook the security of its own people.

“Egypt has never been and will never be against the development of our brothers in the Nile Basin countries as long as this process doesn’t impact Egypt’s water security or hinder the spirit of cooperation amongst us,” he said.

Representatives of the two countries did not reach an agreement on the issue at the meeting, but said they will continue to discuss it.

Meanwhile, an announcement by South Sudan that it has  chosen 16 sites along the Nile to develop hydroelectric dams brought little concern from other NBI countries.

Six of the 10 NBI countries have already ratified an agreement that would replace the colonial-era laws that gave control of most of the Nile waters to Egypt and Sudan.

Akec announced earlier this week that South Sudan will sign the agreement, too, but Sudan and Egypt have both refused to put their names to it.

The Nile Basin Initiative member states are Burundi, Democratic Republic of Congo, Egypt, Kenya, Rwanda, South Sudan, Sudan, Tanzania and Uganda.

Reference: Voice of America

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How Will Artificial Grass Affect Water?

 Editor’s Note:  In earlier Gazette’s we looked at the ins and out, the ups and the downs, of the complicated fake vs. real Christmas tree issue.  Artificial grass, which is growing rapidly in popularity, may be an even more complex water issue than Christmas trees.  Imagine, for example, the impact on storm drain systems if just 10% of a city’s homes had lawns that did not soak up rainwater.  Here’s a perceptive piece from the Wall Street Journal. — Hardly Waite.

 Artificial Grass:  It’s Not Just for Stadiums Any More

by Alyssa Abkowitz

Artificial grass, long considered the bad toupee of landscaping, has gotten a makeover. Manufacturers have developed new “yarns” that make synthetic grass look less shiny and more natural.

Today, six companies make artificial grass in the U.S., and residential sales have increased about 30% a year for the past five years, according to the Association of Synthetic Grass Installers.

Homeowners can have a full lawn of artificial grass installed or use it in specific areas: between pavers in a driveway, in a courtyard, around swimming pools and under swing sets. There are even varieties of synthetic grass for pet owners that include a drainage system, says Brian Karmie, co-founder of manufacturer ForeverLawn in Uniontown, Ohio. Companies also offer specialty grass for putting greens, which use tightly curled fibers instead of straight ones to simulate real putting surfaces, says Nick Vena, vice president of synthetic-grass distributor Purchase Green in San Dimas, Calif.

In recent years, synthetic-grass makers have introduced yarns with a lower luster, skinnier blades and a softer feel to make the appearance and feel of the grass more realistic. While artificial lawns only hit the residential market about a decade ago, they’ve been used in sports arenas regularly since the 1970s.

What is it? Typically made from polyethylene, synthetic grass is made on carpet machines and bound with a polyurethane or latex backing. The grass fibers have short, curled brownish fibers mixed with green and yellow blades that typically are 1¾ inches long. The quality is measured by the product’s face weight, or the weight of the fibers per square yard. Artificial-turf face weights range from 40 ounces to 93 ounces. High-end residential lawns typically use 80- to 93-ounce face weights.

Installation takes about two days: one day to excavate and grade 3 inches to 5 inches of soil, and another day to roll out the carpet and affix it to the ground. Then a sand infill is brushed into the grass to weigh it down and increase its durability, says Bryce Bartlett, director of sales for synthetic-grass installer Conservation Grass of Dallas.

Pros: There isn’t a lot of maintenance—no mowing or watering required—, and most artificial yards last 15 to 20 years. Homeowners with pets may hose down the lawn once a month with a cleaning solution that eats odor-causing bacteria. Owners can brush the blades with a broom to get them to stand up straight if the lawn starts to look matted down. Some states, such as Arizona and California, offer water-conservation rebates for installing synthetic grass.

Cons: Prices can be high, with large, high-quality lawns costing as much as $100,000. Also, the grass gets hotter than natural grass; on a 100-degree day, synthetic grass can reach 108 degrees, says Tony Vena, CEO of Purchase Green.

Price: The lowest-price, 40-ounce face weight is about $1.50 a square foot; the lushest face weight, of 93 ounces, about $4.50. Costs, with labor, range from $7 to $20 a square foot. With labor, costs typically range from $12 to $20 a square foot.

Resources: Association of Synthetic Grass Installers, Conservation Grass, Forever Lawn, Purchase Green, Synthetic Turf Council.Websites: www.asgi.us, www.syntheticturfcouncil.org, www.purchasegreen.com, www.conservationgrass.com, www.foreverlawn.com, www.synlawn.com.

 

Reference: Wall Street Journal.

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 Ancient Water From A Canadian Mine Has the Consistency of Maple Syrup

 

And before you say, isn’t all water on Earth billions of years old, the case of the ancient Canadian water is different. This water has been isolated for all that time, never evaporating, never raining down from the skies, with no contact with the outside world, for a billion years, maybe more. —Reader comment.

Water has been found in bore holes in a copper/zinc mine almost two miles beneath the surface of Ontario that has been shown by tests to be at least 1.5 billion years old–probably older.

In the past tiny amounts of ancient water have been discovered, hardly enough to study, but the water from the Canadian  mine pours out at a couple of quarts per minute. The water is of interest to scientists mainly because it provides clues to the planet’s history and allows speculation about life on other seemingly inhospitable environments, like Mars.

Studying the water may yield new information about the Earth in its earlier stages, including, perhaps, billion-year-old forms of life.

The water itself, after eons of contact with minerals,  is saltier than sea water.  A basic rule of thumb is the older the water the higher the mineral content. One scientist who took a tastes said: “It tastes terrible. What jumps out at you first is the saltiness. … It has the consistency of a very light maple syrup. It doesn’t have color when it comes out, but as soon as it comes into contact with oxygen, it turns an orangy color because the minerals in it begin to form.”

Anyone who has been swimming in Utah’s Great Salt Lake will understand the viscosity comparison.

 

 

 

 

 

NSF/ANSI  Standard 55 For Ultraviolet Systems: A Double Standard

Performance standards for point of use and point of entry ultraviolet purifiers are certified under two distinct classes by ANSI/NSF under standard 55.  Here’s how the  NSF Website describes it:

NSF/ANSI Standard 55: Ultraviolet Microbiological Water Treatment Systems

Overview: This standard establishes requirements for point-of-use (POU) and point-of-entry (POE) non-public water supply (non-PWS) ultraviolet systems and includes two optional classifications. Class A systems (40,000 uwsec/cm2) are designed to disinfect and/or remove microorganisms from contaminated water, including bacteria and viruses, to a safe level. Class B systems (16,000 uw-sec/cm2) are designed for supplemental bactericidal treatment of public drinking water or other drinking water, which has been deemed acceptable by a local health agency.

UV dosage is typically described in units called “Joules,” and it is most frequently expressed in terms of “milliJoules per second per square centimeter,” or

mJ/cm².  Microwatts per second per square centimeter, expressed as µWs/cm2 and mJ/cm2 represent the same dosage and are used interchangeably.  The NSF description above is expressed in microwatts.  The UV dosage is an expression of the UV strength with consideration of how fast the water flows past the lamp.  The higher the number, the higher the dosage. The UV dosage increases as the flow rate of the water being treated decreases, so a UV unit that puts out a dosage of 16 mJ/cm² while treating water at a flow rate of eleven gallons per minute (gpm) will be rated as 40 mJ/cm² if the flow rate is decreased to 4.5 gpm.In addition to the dosage requirement, NSF certification for Class A also involves requirements for monitoring devices, alarms, and safety shutoffs that assure that the equipment is working properly and that the user will not inadvertently use water that has not been treated.  The devices specified are mainly to protect against equipment failure and power outages.

Should you buy only a NSF certified UV unit for your home?

Not necessarily.  The cost is considerably higher and, speaking frankly,  some of the sophisticated electronic features furnished with class A systems are more a bother than a benefit.  A safety device, for example, that shuts off the water to your home when the UV performance dips from being ten times as strong as necessary to a mere nine times as strong as necessary might not make you happy.

Almost all UV units on the market qualify for class B certification, although most manufacturers do not certify to Class B because of the expense.  (NSF certification is very expensive, and it is an ongoing expense; the manufacturer must pass this expense on to the customer.)

Class A certification is in many cases necessary.  With public drinking water facilities (in churches, restaurants, office buildings, for example) use of Class A systems is often required by state regulations, and a few states require Class A for private homes.  In most private homes across North America,  however, non-certified UV systems are much more common and are typically sufficient.

Consider:

Ratings for dosage are figured at the end of the lamp’s recommended life (one year in most cases) and at the specified rate of flow.  If you have a UV unit that is rated for 15 gpm, however, almost all of your residential water use will be done at a fraction of that.  If your unit is rated for 16 mJ at 15 gpm,  your water will be treated at much higher than the 16 mJ rating except for the rare occasions when, if ever, you actually run water at 15 gpm.  And at 15 gpm, on the last day of the lamp’s specified lifespan, the dosage is still double what it needs to be to take care of E. coli,  giardia, and cryptosporidium, the items that are of concern for most residential well owners.

In other words, with UV there is considerable overkill and a great margin for error built in.

 

 

 

 

Fertilizers, nutrients on land too much of good thing in water

Janine H. Rybka and Patricia Carey

  

Fish on Prozac Prove Anxious, Antisocial, Aggressive

By Brian Bienkowski and Environmental Health News

New research has found that the pharmaceuticals, which are frequently showing up in U.S. streams, can alter genes responsible for building fish brains and controlling their behavior.

When fish swim in waters tainted with antidepressant drugs, they become anxious, anti-social and sometimes even homicidal.

New research has found that the pharmaceuticals, which are frequently showing up in U.S. streams, can alter genes responsible for building fish brains and controlling their behavior.

Antidepressants are the most commonly prescribed medications in the United States; about 250 million prescriptions are filled every year. And they also are the highest-documented drugs contaminating waterways, which has experts worried about fish. Traces of the drugs typically get into streams when people excrete them, then sewage treatment plants discharge the effluent.

Exposure to fluoxetine, known by the trade name Prozac, had a bizarre effect on male fathead minnows, according to new, unpublished research by scientists at the University of Wisconsin-Milwaukee.

Male minnows exposed to a small dose of the drug in laboratories ignored females. They spent more time under a tile, so their reproduction decreased and they took more time capturing prey, according to Rebecca Klaper, a professor of freshwater sciences who spoke about her findings at a Society of Environmental Toxicology and Chemistry conference last fall. Klaper said the doses of Prozac added to the fishes’ water were “very low concentrations,” 1 part per billion, which is found in some wastewater discharged into streams.

When the dose was increased, but still at levels found in some wastewater, females produced fewer eggs and males became aggressive, killing females in some cases, Klaper said at the conference.

The drugs seem to cause these behavioral problems by scrambling how genes in the fish brains are expressed, or turned on and off. The minnows were exposed when they were a couple of months old and still developing.

There appeared to be architectural changes to the young minnows’ brains, Klaper said at the toxicology conference. Growth of the axons, which are long nerve fibers that transmit information to the body, was disrupted.

The new findings build on Klaper’s previous research, which tested minnows with the gene changes to see how well they avoided predators. They swam longer distances and made more directional changes, which suggests that the drugs induced anxiety.

The drugs used in the study were among the most common in sewage: Prozac, Effexor and Tegretol. The researchers tested each drug alone and in combination.

“At high doses we expect brain changes,” Klaper said. “But we saw the gene expression changes and then behavioral changes at doses that we consider environmentally relevant.”

However, there is too little evidence to know whether pharmaceuticals are having any impacts on fish populations in the wild, said Bryan Brooks, an environmental science professor at Baylor University who has extensively studied pharmaceuticals in streams and fish.

Any changes in reproduction, eating and avoiding prey can have devastating impacts for fish populations, Klaper said.

The most vulnerable fish populations are those downstream of sewage treatment plants, where prescription drugs consistently show up in higher levels than in other waterways. It’s only within the past decade that technology has allowed plants to test for the chemicals in their wastewater and in waters downstream, though most still don’t, said Steve Carr, supervisor of the chemistry research group at the Los Angeles County Sanitation Districts.

One of the antidepressants tested in the fish – Tegretol – comes into the treatment plants and goes out at near constant levels, said Eric Nelson, a senior chemist with the Los Angeles County Sanitation Districts.

That means the county’s treatment technology does not seem to have any effect on the drug. It comes in and leaves in a very tight range, about 150 to 400 parts per trillion, Nelson said.

Nelson said the two other drugs tested on the fish – Prozac and Effexor  –  are discharged in effluent at even lower levels: between about 20 and 30 parts per trillion. In comparison, the levels that altered behavior of the lab fish were 50 times higher.

When monitoring an Iowa and a Colorado stream, the U.S. Geological Survey found most drugs at levels similar to Los Angeles County’s. However, these low levels could still find their way into fish brains, according to their 2010 study.

Researchers found elevated levels of pharmaceuticals in the stream water two to six miles from the sewage treatment plants. But the chemicals at the highest levels in the water were not the ones most prevalent in the fish brains.

“The fish downstream of the wastewater treatment had elevated concentrations of two antidepressants … Zoloft and Prozac,” said Edward Furlong, a research chemist at the U.S. Geological Survey based in Boulder, Colo. “And these were relatively low in water compared to others.”

Even if the levels released into streams seem low, they are constant, which is problematic, Brooks said.

“The drugs may not be classically persistent like PCBs,” Brooks said. “But they’re pseudo-persistent. The [continuous] exposure of organisms in a stream is equivalent to a chemical that is persistent.”

Some drugs bioaccumulate, or build up, in rainbow trout, according to Brooks’ research. Also, rainbow trout exposed to sewage effluent have pharmaceuticals in their blood at levels as high as those that affect the brains of people, according to research in Sweden.

Brooks said the likelihood of bioaccumulation for pharmaceuticals is high. “People have to take these drugs for weeks before they start having effects. They slowly bioaccumulate in your system,” which suggests bioaccumulation potential in fish, too, Brooks said.

Changes to the brain can affect all kinds of things in fish, Klaper said. And since humans have a similar brain gene structure, the findings raise questions about whether traces of these drugs in drinking water might harm human health.

The U.S. Environmental Protection Agency considers pharmaceuticals an “emerging concern,” and has concluded that the chemicals may pose risks to wildlife and humans. There are currently no federal regulations of the compounds in waste or drinking water. However, 12 pharmaceuticals are currently on the EPA’s Contaminant Candidate List, which are chemicals that may require regulation under the Safe Drinking Water Act.

Studies have consistently found prescription drugs in drinking water at parts-per-trillion levels. U.S. Geological Survey scientists sampled 74 waterways used for drinking water in 25 states in 2008 and found 53 had one or more of the three dozen pharmaceuticals they were testing for in their water. Forty percent of the pharmaceuticals were found at one or more of the sites.

Fifty-four active pharmaceutical ingredients and 10 metabolites have been detected in treated U.S. drinking water, according to a 2010 EPA review.

Studies of children exposed in the womb to antidepressants taken by their mothers show effects on their motor developmentand a higher risk of some birth defects.

But health officials say the levels found in some drinking water are too low to cause harm.

According to a 2012 World Health Organization report, the “trace quantities of pharmaceuticals in drinking water are very unlikely to pose risks to human health.” The report said that the amount found in drinking water is usually 1,000 times lower than doses expected to have an effect on a person.

But Klaper said that in light of the gene changes in fish brains, officials may need to rethink what is considered safe.

“Fish do not metabolize drugs like we do,” Klaper said. “Even if environmental doses aren’t thought to be much for a human, fish could still have significant accumulation, and, it appears, changes in their brain’s gene expression.”

This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.  It is reprinted here for Scientific American. 

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Silver Inhibits the Growth or Bacteria in Water Filters, But It Is Not a Serious Biocide

Silver has for some time been used as an ingredient in water filters, especially carbon drinking water filters and ceramic filters.

It is also used in swimming pool purification devices.

When silver is used in a water filter, the EPA regulates it as a pesticide, so an EPA approval often appears on the product label. This has led to a false notion among the public (which is encouraged, I regret to say, by some manufacturers of water filters that contain silver) that such products are “certified” by the EPA as a guarantee of performance.  The EPA does not certify the performance of any product.  The EPA approval merely means that the filter contains so little silver that its water can be consumed safely by humans.

Another common false belief about silver in water filters is that it “kills bacteria,” meaning that it makes unsafe water safe to drink.  It does not.  Silver is classified as a “bacteriostatic” agent, not a biocide.  This means merely that it inhibits the growth of bacteria in existing filter beds.  For that reason it is sometimes added to carbon filters, since carbon provides a fertile growing place for harmless, non-pathogenic. heterotrophic bacteria.  Silver serves as a bacteriostatic agent, inhibiting that growth.  It can also serve a useful function when it is embeded  ceramic filters, where it can prevent bacteria from growing through the ceramic wall.

Although recent studies indicate that if given enough time silver can produce a 6 log reduction of bacteria, it is an extremely slow acting killer and its usefulness in this area is very limited.

 Street Cleaning Machines Are Essential Tools for Maintaining Clean Water

 

We usually think of street sweepers as big noisy machines that stir up dust and pick up some dirt, leaving the street looking a little nicer.  What we don’t consider is that street sweepers are an essential part of water treatment.

What we  call ‘street dirt’ is composed of heavy metals and other pollutants—items that may be killing fish when they get into waterways via stormwater runoff. Cities use media filters to clean stormwater, but it is estimated that effective street cleaning can greatly lessen the cost of filtering.  Cleaning the street as compared with filtering costs about one-forth as much, in fact.

Heavy metals like cadmium, copper, lead, zinc are specific pollutants that are found in abundance in “street dirt.”  In 1972, in the first USEPA publication ever on stormwater, street dirt was named as “the primary source of contamination, in terms of mass.”

Much of the toxic debris that washes to storm drains from the street is from automobiles.  Brake pads, for example, especially cheap brake pads, deposit large amounts of copper into the streets.  This copper ends up in the water supply unless it is caught in a filter or, more economically, swept up by a street cleaning machine.

Street sweeping machines vary in sophistication.  Early models, which go back centuries, were used for picking up horse manure before the advent of the automobile.  In the early 20th century, many US cities used them, but they were of limited effectiveness.

Mechanical machines, which use a main broom and conveyor belt to pick up material,  have been around at least 100 years. Their basic design hasn’t changed that much, although impressive improvements have been made, such as the broom design and speed, and the conveyor belt speed and alignment.  The mechanical machines are still the most popular, and perhaps 90% of the sweeping machines in operation are of the mechanical broom design.

Newer designs include “regenerative air” units which in one motion blow air down on the pavement to dislodge debris then immediately vacuum the dirt into a hopper.  These are sometimes unpopular because unless they include air filters they stir up lots of dust.  Vacuum machines can be very effective.

Even more advanced designs use water.  One machine features “rotary arms with nozzles on the end that  blow water down on the pavement; the back end of the machine features a powerful vacuum and a squeegee that sucks up the water and the debris it contains.”

The “state of the art” machine called the Schwarze A7000 costs in the neighborhood of $170,000.

The effectiveness of the machine, of course, is determined by how much dirt the machine actually picks up.  Ineffective machines simply move some of the dirt to a different location.  The worst street cleaner of all time, of course, as well as probably the stupidest machine ever devised, is the common leaf blower, which does not remove dirt but simply moves it to a less visible spot.