AGSM EXAM 1

Watershed/Drainage Basin

Land area that drains water to a particular stream, river, or lake

How to identify watershed/drainage basin

tracing a line along the highest elevations between two areas on a map, often a ridge

Watershed Boundary 

Continental divide separates the flow of water from the Pacific ocean and Atlantic ocean

Public Water Supply

Water withdrawn by public governments and government licensed or approved entities and then delivered to us

Consumptive use

percentage of water withdrawn that 

• Evaporates

• Used in plants

• Incorporated into products

•  Consumed my Humans or Livestock

• Removed from immediate water environment

MGD

Millions of Gallons per Day

Drawdown

a lowering of the groundwater surface caused by pumping. Cone of Depression. Pumped out faster than it can replenish

Cone of Depression

a cone-shaped dip in the underground water table that forms around a well when water is pumped out faster than the surrounding aquifer can replace it. result of drawdown

Artificial Recharge

water is put back into groundwater storage from surface water supplies

Injection Well

injects treated wastewater directly into the ground. Wastewater pumped into well for dispersal or storage.

Injection Well sites

aquifers that don't deliver drinking water, unused aquifers, or below freshwater storage

Water Supply Diversification

Effluent

water that flows from a sewage treatment plant after is has been treated

Soil erosion

nutrient or chemicals attached to eroding soil particle get relocated

Acre Feet

unit of water volume used in US to reference large scale water resources

Equivalent to 325,852 gallons

How many gallons are in an acre foot

325,852 gallons

2030 existing TX Water Supply

15.5 million acre feet

Surface Water 46% - 7524781 acre-feet

Ground Water 49% - 7202299 acre feet

Reuse 5% - 

Texas Surface water

• 3700 named streams

• 15 named rivers

• 23 major river basins (watersheds)

Major Reservoirs Purpose

Flood Control, Hydroelectric power, Water Supply. Mainly Water Supply today

How many major reservoirs does Texas have

208

Estuary

where fresh and salt water mix (bay, marsh, where a river meets and ocean)

Transpiration

water that's absorbed by plants is evaporated into the atmosphere from the plant surface

Evapotranspiration

the sum of evaporation and transpiration

Turbidity

Basically how clear it is/how easy you can look through the water. Measure of water cloudiness by nephleometer

Measured in Nephelometric Turbidity Units (NTU)

Flood Plain

strip of flat and normally dry land alongside a stream, river, or lake that's covered by water during a flood

Giardiasis

disease caused by drinking water that isn't filtered or chlorinated. Infection caused by Giardia Intestinalis parasite

Associated with Children

Maximum contaminant level (MCL)

greatest amount of contamination that can be present in water without causing any health issues

Drip irrigation

methods where pipes or tubes filled with water slowly dripping onto crops

Irrigation

controlled application of water to plants

Black Water

Household water from toilets, dishwashers, and kitchens

Contains a lot of organic matter

Grey Water

Household water from showers, baths, and washing machines

Oxygen Demand

Need for molecular oxygen to meet the needs of biological and chemical processes in water

Hydrology

study of occurrence and movement of water on and beneath the surface of the earth. 

Stream network

drainage of excess precipitation occurs via a hierarchical stream network

Watershed Order

Main streams converge into fewer streams and so on until the main stream/channel

Caddo Lake

Only natural lake in Texas

River Authorities

• Water Supply Management

• Flood control and floodplain management

• Water quality protection

• Environmental stewardship

• Wastewater and utility services

• Recreation and public access

• Infrastructure development and financing 

How many major aquifers are there

9

Whats a major aquifer

underground layer water bearing rock, rock fractures, or unconsolidated materials such as gravel, sand, or silt. large amount over large area

How many minor aquifers are there

22

What’s a minor aquifer

Produces a minor amount of water over a large area or a large amount of water over a small area

Law of biggest pump

Landowners can pump as much groundwater as they can capture, even if it drains the water from under a neighbor's land and causes the neighbor's well to go dry. No liability

Rule of Capture limits

•Malicious taking water for the sole purpose of injuring his or her neighbor

•Willingly or wantonly wasting groundwater

•Negligently drilling or pumping from a well in a manner than causes subsidence

•Pumping from a contaminated well

•Trespassing in order to pump groundwater

Ground Water Conservation District

Manages how much water is taken from an aquifer to manage sustainability 

Hard Water

higher amount of minerals (calcium and magnesium)

Soft water

lower amount of minerals (calcium and magnesium).

Spring and Mineral Water 

Hard Water

Purified and Distilled Water 

Soft Water gone through reverse osmosis and distillation

TDS (Total Dissolved Solids)

measurement for how hard or soft water is

Artesian Water Well

taps into a confined underground

Brackish Aquifers

Geologic zones within major or minor aquifers with a Total Dissolved Solids (TDS) of 1,000 to 10,000 parts per million

Riparian Water Rights

landowners adjacent to a flowing stream or river can use the water.

Inter-basin Transfer

movement of water from one significant basin to another

Subsidence

sinking of the ground because of underground material movement, most often caused by the removal of water, oil, natural gas, or mineral resources out of the ground by pumping, fracking, or mining activities.  

Edwards Aquifer

where most of san antonios water comes from

Casing

made of carbon steel, plastic, or stainless steel. Drilled underground to maintain the well opening

Submersible Turbine Pump

push water up through a pipe installed in the well instead of pulling it with suction. used at shallow depths or in deeper wells. Electric motor drives pump. Sized by horsepower.

Pressure Tank

keeps pressure even

Artesian Water

groundwater that is under pressure when tapped by a well and is able to rise above the level at which it is first encountered

Microbial Well Contaminants

• Microbial 

  • Fecal 

    • Feedlots

    • Wildlife

    • Poorly maintained septic systems

Well Contaminants: Local land use practices

• Nitrogen and Phosphorous from fertilizers

• Chemicals from herbicides

Well Contaminants: High concentrations of naturally-occurring contaminants

Arsenic, Radon

Water column

the higher it is, the more water pressure we have at the bottom

Water Tower

the amount of water it holds doesn’t matter, the height and the pressure reading at the bottom is what matters

Pressure Conversion

2.31ft = 1psi

feet/2.31 = psi

How many people does Houston serve

2.3 million people across 671 miles.

Regional water provider for Harris County and portions of 3 surrounding counties

How many gallons of Water does Houston treat annually

146 billion gallons

What percentage of Houston’s drinking water is surface water

86%

What percentage of Houston’s drinking water is ground water

14% (from Evangeline and Chicot aquifers)

What lakes and rivers do the city of Houston own

70% of livingston and conroe 

100% of lake houston

70% of the future allen’s creek reservoir

Lower Trinity River

Ogalla aqufier

the largest freshwater aquifer in the United States

Flow Meter

measure the amount of water used

Cryptosporidium (AKA Crypto)

microscopic parasite that causes the diarrheal disease cryptosporidiosis

Tributary

a smaller stream or river that flows into a larger body of water

Leaching

water moves down through soil, rock, or waste, dissolving and carrying away soluble minerals, nutrients, or pollutants

How many miles of rivers and streams are in Texas

191000

How many named of streams are in Texas

3700

Longest river in Texas

Brazos River

Whats the most common surface water use

Municipal

Whats the most common ground water use

irrigation