Question

the fault line threatening dams
by jim carlton
dec. 24, 2017
fremont, calif. - the coastal mountains that frame this working - class city next to san francisco bay harbor a hidden menace: a
seismic 10 miles away that sits next to an active earthquake fault,
which experts say could cause a dam break and flood thousands of
homes.
the potential threat is so severe, the owner of the calaveras
reservoir decided to build a replacement dam. but seven years after
real work began the dam is unfinished and isnt expected to be
complete until 2019 - four years behind schedule.
the owners transparency the calaveras reservoir project show how
concerned it can be to repair or replace an old dam, which is of growing

1. why did the owner of the calaveras reservoir decide to

build a replacement dam?

1. why is it especially dangerous that close to 1,100 dams

rated as having high or significant risk of failure are
located in california? use evidence from the text to
support your answer.

1. imagine youve been placed in charge of a large project

to repair or replace over 2,170 dams in the united
states that are considered deficient.
explain what you would consider in your decision about
which dams to repair or replace first.
use information from the text to support your answer.

Explanation:

The text discusses dam - related issues such as the danger of dams near fault lines (specifically the Calaveras Reservoir dam near an active earthquake fault), high - risk dams in California, and considerations for dam repair or replacement. To answer the questions:

• For the question about why the owner of the Calaveras Reservoir decided to build a replacement dam, the text mentions that the potential for a dam break and flooding thousands of people due to its proximity to an active earthquake fault was a major factor.
• For the question about why it's especially dangerous that close to 1,100 dams rated as having high or significant risk of failure are located in California, the text implies that California has seismic activity and population density that could lead to severe consequences in case of dam failures.
• For the question about which dams to repair or replace first among over 2,170 considered deficient, factors like proximity to faults, potential for catastrophic failure, and population exposure would likely be considered as per the context of the Calaveras Reservoir case.

Answer:

1. The owner of the Calaveras Reservoir decided to build a replacement dam because it is located next to an active earthquake fault, which could cause a dam break and flood thousands of people.
2. It is especially dangerous that close to 1,100 dams rated as having high or significant risk of failure are located in California because of the state's seismic activity and the potential for large - scale damage and loss of life in case of dam failures due to earthquakes, as well as its population density in areas near dams.
3. When deciding which of the over 2,170 considered deficient dams to repair or replace first, factors such as proximity to active earthquake faults (like the Calaveras Reservoir dam), potential for catastrophic failure leading to large - scale flooding, and the number of people exposed to the risk in case of a dam break would be considered.