1 / 16

water

water. a renewable resource: the hydrological cycle. the potential for water scarcity. surface water (rivers lakes reservoirs) ground water (aquifers) 90% fresh water only 2.5% available on a renewable basis the rest is finite / depletable

hector-andrews
Download Presentation

water

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. water

  2. a renewable resource: the hydrological cycle

  3. the potential for water scarcity • surface water (rivers lakes reservoirs) • ground water (aquifers) • 90% fresh water • only 2.5% available on a renewable basis • the rest is finite / depletable • accumulated through geologic time, once used cannot recharge

  4. other water issues • quality further limits supply potable water • land subsidence • settling / sinking of earth surface due to excessive withdrawals of gw

  5. efficient allocations:surface vs. groundwater • surface water • how to allocate a renewable supply among competing uses • intergenerational effects less important (future supplies depend on natural phenomenon, e.g. rain, rather than current allocation) • groundwater • withdrawing now affects future supply

  6. efficient allocation: surface water • balance btw users • marginal net benefit equal across users • handle variability • above-average and below-average flows must be accommodated

  7. efficient allocation: groundwater • if withdrawal > recharge, eventual exhaust resource • MEC rises over time as water table falls • pumping would stop: • no water left • MC pumping > benefit of water or MC of backstop resource (desalination) • price rises over time until choke price or switch point

  8. the current allocation system • riparian doctrine • early settlers • adjacent owner got right • as demand grew, less appropriate • diversion necessary • prior-appropriation doctrine • gold rush / mining • first to arrive got right • usufruct • state ownership; right to use • federal govt took over; building dams, diverting water

  9. are these efficient allocation systems? • restrictions on transfers • hard to equalize marginal net benefits • federal reclamation projects • regional vs. national benefits • water pricing • both price and rate structure • should account for storage, treatment, distribution, and value of water (this often left out) • common property problems • low incentives to conserve

  10. efficient pricing • MC, not AC • customer should be charged mc of supplying last unit • usually charged cost of running operation (historical costs) • no scarcity rent • water inefficiently cheap; excessive demand for water

  11. potential remedies • reduce restrictions on transfers • get rid of “use it or lose it” ethic • water markets/ water banks to transfer water • getting the prices right!

  12. agricultural pricing schemes

  13. agricultural pricing schemes • 2 part: volume pricing + fixed fee • output pricing: linked to output not water use • input pricing: assessed taxes on water-related input (not on water itself) • block rate / tiered pricing: seasonal peaked demand • area pricing: how much area, not how much water (mc using extra water is zero!)

  14. utilities pricing: uniform & declining block rates(inefficient)

  15. utilities pricing: inverted block & seasonal rates(potentially efficient)

  16. US pricing structures

More Related