Hello everybody my name is Zohir Chowdhury, and today we will talk about Southern California's
sources of water so in order to understand the sources of water for Southern California it is
extremely important to understand the population distribution the population that needs the water
and the availability of the water in the state on the right side of the map in here we can see
the population distribution for the state and of course the cities of San Francisco Los Angeles
and San Diego the three more the three biggest cities contain most of the population and the
remaining population spills over into Sacramento Fresno and some of the coastal cities that are
more or less populated eighty percent of the population lives in the main urban eyes areas
another ten to fifteen percent another ten to fifty percent lives in the suburbs of some of
these areas so about ninety five percent of the entire population is living in the southern areas
of the state southern coastal and then in the central and coastal Central and svehla coastal
area of the state leaving most of the state with only five percent of the population in terms of
water availability on the other hand the southern part of the state is pretty dry it's an arid area
that doesn't get a lot of rainfall on the northern side on the other hand it gets significant amount
of rainfall as well as snowfall through more or less in the lot of in the wintertime but
also throughout the year it's significant where rainfall especially in the coastal area in here
what this means is that there's a lot of water on that on the northern side and there's not
enough water on the southern side so in order to meet the populations water need it is extremely
important to be able to reallocate this water from the northern area where it's water rich to
the areas where population leave and needs need the water to the southern and central area also
know it's important to understand the centrality of California in here its agricultural rich and
agriculture needs a lot of water so a lot of water in the state also is used to provide
food for the population which is grown in the southern southern areas and in the central area
and the southern area in here what a supply for Southern California as we mentioned it's coming
from three sources corrado river area sacramento river delta as well as a snowpack melt in the
Sierra Nevada mountain and here is the corridor River watershed here is a Sacramento Delta area
and then Sierra Nevada mountains in here where it gets a lot of snowfall only 10 to 20 percent of
the water used in Southern California it's from local sources mostly coming from rain and been
replenishing the reservoirs and replenishing the aquifers the remaining 80 to 90 percent is
imported from the sources as I mentioned here in the map you can see that were sources from
for Los Angeles here the sources for San Diego the three sources that we just mentioned they
are 242 Mile aqueduct was been built to bring the water from Lake Havasu which stores water from the
Sacramento River area and brings it to Southern California another 444 mile-long aqueduct which
is the California Aqueduct has been built to bring water from the Sacramento Delta area into
the Southern California area the Los Angeles Aqueduct in here brings the snowpack in the
Sierras and brings brings it into the California Aqueduct which in turn goes into the Los Angeles
area San Diego on a distribution system taps into this various sources by connecting the aqueduct
with state aqueducts and so the first aqueduct in here and the second I could have been here as
shown the water that is brought from all of these sources gets stored into about 20-25 reservoirs
and some of them are shown in here like like Lake Hodges reservoir near Escondido Sutherland
reservoir in here and then we have that El Capitan reservoir and the Santee reservoir and we have the
more liquid reservoir at the Miramar reservoir as well as the upper otai and the lower order
reservoir all of these reservoirs essentially are man mailed man-made structures man-made Lakes that
have been built by damming a specific area of the geographic location in order to bring the
water and collect it behind the dam and create an artificial lake as a result of that water from all
of these reservoirs is used up in various areas in the in the city such as shown in here this is
the service area for the Miramar service area whereas in here you have the Alvarado service
area and here you have the auto service area so the mo sources of the water one big source
of the water in the state is the snowpack that the state gets in the Sierra Nevada mountains
here we can see the Sierra Nevada mountains with snow packs during the wintertime the suniverse
snowpack water content has been declining over time in fact in here from 2005 2015 you can see
a progressive decline of the water of course 2011 had a significant amount of snowfall which caused
a rise of the water but in subsequent year all of the water all of the snow was you step and now
back to the 15 record level the record low level of snow has been recorded like 15 in fact 2015
compares with the lowest years if we look at the historical data in here 2017 and 2014 being the
two previous low ones in 2015 vanilla westrom here also you can see 50 years of snowpack snowpack
data this is the average so above average years you can see them in here and below average you
can see them in here and you can see that lowest 2015 is shown in here with 14 13 and 12 also been
pretty low however the 2017 we got significant snowfall as you can see in here but 2018 so
far has been very very dry more or less dry the snowpack information is provided in the website
this is showing the 2017 snowpack information which was very heavy snow and we can see in
here that a lot of this of the Sierra Nevadas snow was replenished during this very snowy year
however the states still struggling with significant drought issues on the other
hand the other source which is major is the Colorado River Basin as shown in here Corona
River system starts in the Rocky Mountains of Wyoming and then river passes through state
of Wyoming Colorado Utah Arizona Nevada and barely borders California before going into
Mexico this watershed in here it's home to 40 million Americans located in seven states and
water in this watershed provides the water for all of this medium for all of these 40 million
people it is the fastest growing area in the u.s. in terms of population however in here the water
supply and the demand over the years have been changing in the past water supply was much much
higher with respect to demand of course the population was much lower in here over time
populations are increasing more populations that are moving in this area because of climate and
work and other reasons however the water supply as you can see overall has shown a declining trend
and reaching levels that are one of the lowest in history and the man on the other has been
rising and exceeding the supply in this area the water location from corner River is allocated as
follows 27 percent of the water is California gets it and 23 percent Colorado and other states as you
can see gets less and less and less with Mexico getting only nine percent so u.s. overall gas 91
percent makes you gets about nine percent most of the water that we get from the corner River
is used for irrigation purposes to provide food for all of the population in here so let's do a
quick constant check which of the following is not a source of water for Southern California
e they all are sources of water for Southern California we get water from the Sierra Nevada
Sacramento Colorado as well as local rainfall and local groundwater aquifer another con
subject to false currently water supply from the Colorado River by far exceeds the water
demand in the region false right now demand it's actually higher than supply that's all thank you