LECTURE 1: FALL TERM 2013
- Catalyst of modern civilization : groundwater
- Sustainable water management
- Green revolution “agriculture”
- People managed groundwater as surface water.
- Surface water: found in lakes and rivers (measured, pushed around, irrigated, piped)
- - Romans moved water around, collected water and built structures to convey the water.
- Darcy’s law dates back to 1856 (155 years old) . Did basic experiments to create fountains ,
came up with darcy’s law. Fundamental to groundwater flow. Groundwater flows thru the
system based on darcy’s law. Ohm’s law is also imp.
- Aquifers in the subsurface allow water to flow to well, represents huge storage reservoirs
- Meinzer’s work dates back to 1920’s
- Groundwater exists in the subsurface, very ubiquitous
- Out of the 4 litres of water available on the planet, 3 of them are frozen water (inaccessible)
- 98% of water is groundwater (volumes of storage)
- Flow velocities: 1 m/s in highland creek. 1m/day . Sometimes it may be 10 cm/day
- People idealize that rocks/soil are a filter system, and keep dumping contaminants.
- Surface water flow, some goes into lakes and lakes discharge into rivers and eventually gets into
oceans (FAST ROUTE)
- Anything that infiltrates becomes groundwater or aquifer recharge and then discharges to
surface water or takes a very long route and discharges to oceans (OVER-TIME ROUTE)
- IWRM: manage whole water cycle
- Aquifers: saturated with water (porous rock)
- Aquitards: silty rocks, fine grained rock , get a lot of water in them but don’t transmit very well
- Aquicludes: stores water as well but are imperbeable , went out of fashion for 30 years but is
coming back again. There’s no such thing as an aquiclude b/c everything transmits water if
enough pressure is applied to it
- Aquifuge: tough to find, solid rock - Hydraulic conductivity is how easily water flows through rock and porosi