Category Archives for "waterpedia"

How Much Does a Cloud Weigh?

cloud weighed on a kitchen scale.Do clouds have any weight at all? After all, don’t they float like a balloon in the air filled with helium? If you attach a helium balloon the the platform of a kitchen scale it wouldn’t register any weight at all, so why would a cloud? To answer this, let me ask if you think atmospheric air has any weight, this is actually the more important question. Are you familiar with air pressure the tool known as a barometer are? If yes, then you understand that air DOES carry weight. At 0′ (sea level), the weight, or pressure, of air is approximately 14.5  lb.. PSI (1 km per sq. centimeter).

If air has weight, then it must also possess density, which is the weight of a chosen volume, for example cubic inches or cubic meters. If clouds consist of particles, then they must possess weight and density, correct? The answer to why clouds seemingly “float” lies in the density of the sheer volume of cloud material, being less than the density of a similar amount of dry air. As oil floats above H2O because it possesses less density, clouds seemingly “float” on the air due to the moister air in clouds possessing less density than dryer air.

California Water Use Efficiency

The California program known as “turf and toilet” is financed by the Proposition One water bond, which was approved by California voters. It will carry out Governor Brown’s Executive Order of April on drought to further conserve water use in homes and buildings via replacement of more than ten million sq. feet of landscaping and upgrading water-wasting toilets.

D.W.R. will oversee the 2 rebate programs, which offer a one hundred dollar consumer rebate to discard one toilet per house and up to two dollars per square ft. for replacing lawns. More information at

State Agricultural Water Management Plans

There are an approximately 53 water suppliers that rise to the 25,001+ acre limit representing more than 4 million irrigated acres

There are an approximately 39 suppliers of agricultural water to 10,000 to 25,000 irrigated acres representing about 600,000 irrigated acres.

  • H2O providers >25,000 acres minimum and submitted – 40
  • H2O providers >25,000 acres minimum, notified DWR as in progress – 0
  • H2O providers > 25,000 acres minimum, not submitted – 14
  • H2O providers 10+ -25,000 acres minimum and submitted – 22
  • H2O providers 10+ -25,000 acres minimum, notified DWR as in progress – 8
  • H2O providers 10 + -25,000 acres minimum, not submitted – 9

California Rainfall Deficit

Will the upcoming rainy season put a big dent into California’s precipitation deficits?

The answer is only with lots and lots of rain. As of the beginning of Sept, California is has 5-year rainfall deficits (starting in October 2011) of eight inches in the dryer southeast part of the state to almost fifty inches along the northern coast.  In the State of California, four year rain accumulations  (2011-2014) have been about 54-75% of average during that time. To put the shortfall into perspective, every region in the State is missing at least one years worth of rainfall. In fact, the southern coast of the State is missing about two year’s worth of rain (1.8 years to be precise). This shortfall isn’t so much of a hole as it is a giant canyon.

One yardstick used by the U.S. Drought Monitor group to declare drought is whether rainfall totals are in the lower 20 percent of the available record. For 5-year rainfall totals (October 2011 – September 2016) to get out of the lower 20% of records dating to 1928, precipitation totals from October 2015 to September 2016 must be higher than 135-160% of normal in the Northern part of the State , 160%+ of normal in the southeast to 198% of average in the San Joaquin Valley. This is a alot of rain/snow.

Hoover Dam Illuminated

Hoover Dam “Lit Up” Turquoise

To honor National Women’s Lung Health, the American Lung Association’s LUNG FORCE collaborated with partners to illuminate popular landmarks, including Hoover Dam, the color turquoise to celebrate the LUNG FORCE Turquoise Takeover. Supported by the Bureau of Reclamation, Hoover Dam was “lit up turquoise” on May 8th, just after sunset. The public can see the illumination from 8:30 to 10:30 in the evening at the observation bridge over Hoover Dam  on May 9th through the 11th. “Lung cancer is the leader cancer cause of death of women, and yet only 2 percent of women refer to lung cancer as a primary health concern,” said Kristina Crawford, oAmerican Lung Association Nevada’s executive director. “National Womens Lung Health Week is a excellent opportunity for us to expand awareness about lung cancer and give support for lives touched by the disease. We are very happy to join with Hoover Dam in lighting the dam for the LUNG FORCE Turquoise Takeover and bring efforts to bear to force and end to lung cancer.”

Nevada Water Data Set

A rasterized image of depth to groundwater dataset for Nevada. The origin of this dataset is a statewide watertable contour dataset made from watertable contours gathered from the 1940's to 2004 and published in thirty-eight reports from the sixties to 2004, depth to groundwater contours from Static Groundwater Levels of Nevada first published in the 1970's, and depth to groundwater contours of Diamond Valley made available in 2006.

Watersheds and Rivers

Watersheds & Rivers

It is very simple to explain why rivers exists on Earth— gravity! You’ve familiar with “water seeks its own level,” but in reality, water is seeking the centerpoint of the planet, just like everything else is. In more practical terms, water usually seeks to flow directly to the oceans, which are, of course, at sea level. So, wherever on Earth water is, it attempts to flow downhill. With the planet being a very not-level place, water ends up filling the valleys and depressions in the terrain as rivers, streams, and lakes.

When observing the location of rivers and streams and the amount of water flowing in rivers, the key idea is the river’s “watershed”. If you are standing on level ground right now, just look downward. You are standing, and others are standing, within a watershed. To define a watershed, it is the region of land where all water falls into it and it drains away as it goes to the same place. Watersheds are be as small as a footprint or massive enough to engulf all the lands that drain water into the rivers,  that drain into the Bays of the Ocean. Bigger watersheds almost always contain multiple smaller watersheds. It is all dependent on the point of outflow; all of the terrain that drains to the outflow location is the watershed of that outflow location. Watersheds are vital because the river-flow and the quality of water of a river are impacted by things, human-induced or not, occurring in the land area “upstream” of the river-outflow point

Underground Groundwater Flows

There are rivers flowing below our feet … a myth?

Is it an old wives tale that there are rivers of flowing underground, beneath us? Do you think its not true? Actually, it can be categorized as a myth. While there are some caverns, and lava / ice tubes, and even horizontal springs with carrying water, , the bulk of water underground takes up the spaces between rocks and other subsurface material. Generally, water that is underground is similar to water in a sponge. It takes up the the spaces between soil, rock, and other substrate particles. At a depth well below the surface of the land, the space between soil and rock particles can be completely filled with water, creating an aquifer from which water can be pumped from groundwater and used by people.

Water Storage in the Atmosphere

Cycle of Water: Atmospheric Water Storage

A lenticular cloud over New Zealand.
Lenticular cloud / New Zealand.
Photo Credit: Chris Picking

The cycle of water is about storing and moving water on, in, and high above the Earth. While the atmosphere may not be a perfect warehouse of water, it is the pipeline used to transport water around the world. Evaporation / transpiration morph liquid to water vapor, which rises up to the atmosphere on rising currents of air. The cooler temperatures high above allow the condenses the vapor into the clouds and trade winds push the clouds around the globe until the water drops as rainfall to further the water cycle. More than 90 percent of h2O in the atmosphere is created by evaporation from bodies of water, while the other 10 +/- % is the result of plant transpiration.

There is perpetually water in our atmosphere. Clouds are the most visible signals of atmospheric water, but clear air contains water vapor, particles of water too small to be seen by the naked eye. One guess of the volume of h2O in the atmosphere at any time is about approximately 3,000 cubic miles, or 12,800 cubic km. (km3). That may sound substantial, but it represents only about 0.001 percent of the planet’s water volume. If all of the h2O in the atmosphere fell at once, it would cover the globe with only about 1 inch of water.