Can you please answer for me these objectives. Floods Application The Federal Em
ID: 235315 • Letter: C
Question
Can you please answer for me these objectives.
Floods Application
The Federal Emergency Management Administration (FEMA) prepares flood maps for most areas of the United States. As a geologist working for an insurance company, you need to know how flood zone maps relate to flood risk and insurance rates. To complete your work, you will use a Flood Insurance Rate Map (FIRM), which is a map that shows the different flood hazard zones within a community. As you can see in the accompanying chart, insurance rates vary widely depending upon the map zone that a property is located within.
Floods occur when rivers overflow their banks due to increased water flow, which can be caused by intense rainfall or snow melting upstream. As a geologist working with risk-assessment scenarios, you know that a 100-year flood has a 63% chance of occurring in any 100-year period of time, while the same chance exists for a 500-year flood level occurring in any 500-year period of time.
To complete your work, you will use the links on the left, which will help you
· Understand that a site’s flooding risk can be determined by using maps from the Federal Emergency Management Administration (FEMA),
· Understand that flood insurance premiums are determined by using flood insurance rate maps and characteristics about the property, and
· Determine the flood insurance premium for a site by using a flood insurance rate map of the area and a schedule of premiums from FEMA.
Part A - Flood zones
Flood zones are designated by the 100-year and 500-year flood boundaries. The prior indicates a greater risk for flooding. Sites located within a zone compared to sites located on a zone boundary vary for risk. Review the accompanying map and the content provided at the Legend link in the introduction to identify which sites are located in which zones and how that relates to flood risk. Learn more about each neighborhood by clicking on its name on the city map located at theMap link.
What does each zone designation mean for each neighborhood?
Select all that apply.
1. A majority of Riverside is safe from any flood smaller than the 500-year flood event.
2. Point Park lies within Zone A and has a low chance of being affected by flooding.
3. The Hazard City railroad on the south side of the river lies in Zone B and is only in danger of floods larger than the 100-year flood event.
4. All of Downtown is within Zone C and is relatively safe from flooding.
Part B - Flooding probabilities
Examine the map below, and determine the flooding probabilities. Check out the flood zone Legend and Map links for information that helps determine flood risk, such as slope, elevation, and stream/river proximity. Be sure to review the information below the map at the Map link.
What do the zone designations for each site mean for flood probability?
Select all that apply.
1. Site 2 has a greater probability for flooding than Site 1.
2. Site 1 has a greater probability for flooding than Site 3.
3. Because the elevation of Site 2 is less than the nearby base flood elevation, it will be at less risk for flood than if its elevation were above 838.
4. Site 3 has a high probability for flooding due to its elevation.
Part C - Flood insurance rates
Examine the zone map again and the rate chart that is provided in the introduction of this lesson to determine the flood insurance rates for the three sites indicated based on probability of flooding. Note that not all labels will be used.
Drag the appropriate labels to their respective targets. Not all labels will be used.
Part D - Rivers and elevation
On the Hazard City map, the blue feature running through Riverside and Ralston is a river system. Which direction is the river system flowing through Hazard City?C
Choose from (1, 2, 3, 4)
1. toward north
2. toward east
3. toward south
4. toward west
Part E - The effect of roads on flooding
Highways are indicated by bold red lines on the map. How can Highway 857 potentially affect flooding in Hickory Estates?
Choose from (1, 2, 3, 4)
1. Because of the impermeable road surface, both Route 857 and Route 342 would cause floodwaters to be potentially trapped in Hickory Estates, causing flooding.
2. The road would have no effect; flooding is not affected by urbanization.
3. The road could block floodwaters and cause the river to flow south.
4. The bridge across the river could block water flow, causing higher water levels and increasing the potential for flooding.
Part F - Stream gradient
Stream gradient is calculated as the change in elevation (measured in feet) divided by the distance traveled (in miles). Using the base flood elevation lines on the map, what is the stream gradient of the main trunk of Clearwater River shown on the map? Recall that 5280 feet = 1 mile.
Choose from (1, 2, 3, 4)
1. approximately .5 feet/mile
2. approximately 3 feet/mile
3. approximately 15 feet/mile
4. approximately 10 feet/mile
Part G - Flooding risk
Which community has the least risk of flooding?
Choose from (1, 2, 3, 4)
1. Riverside
2. Downtown
3. Walnut Heights
4. Ralston
Part H - 100-year flood risk
According to the map, how many total buildings in Hazard City are at a high risk for flooding during a 100-year storm event? Note that buildings are marked as black and red squares on the map.
Choose from (1, 2, 3, 4)
1. more than 20
2. 0
3. 3
4. 13
Part I - Damming rivers and future floods
If the Palouse River is dammed upstream, how might this affect future flooding in Ralston?
Choose from (1, 2, 3, 4)
1. It would have no effect.
2. It could lower Clearwater River, decreasing the amount of water in its tributary, but this would have no effect on Ralston.
3. It would raise Clearwater River, increasing the amount of water in its tributary, and increase the risk in Ralston.
4. It could lower Clearwater River, decreasing the amount of water in its tributary, and decrease the risk in Ralston.
Part J - Past flooding events and current flood levels
Paleoflood (ancient flood) deposits have been found in parts of Ralston that are currently in Zone C. Which of these answers provides a possible explanation for this finding?
Select all that apply.
1. The river system experienced a flood greater than the 500-year flood.
2. None of these are possible explanations.
3. The river was previously located closer to Ralston and has moved.
4. The flood map is drawn incorrectly.
Part K - Flood insurance and property values
You are buying a home in Ralston, located in Zone B with no previous flooding. The home costs $250,000 and has no basement. How much should you expect your flood insurance rate to be?
Choose from (1, 2, 3, 4)
1. $221/year
2. $773.50/year
3. $552.50/year
4. $441/year
Part L - Using flood zone contours to determine elevation
A flood greater than the 500-year flood travels through Hazard City. Which side of the river would be safest to live on?
Choose from (1, 2, 3, 4)
1. It is impossible to tell.
2. North
3. South
4. Both the north and south will be equally affected.
Part M - New construction and flooding downstream
A new housing development is being built upstream. How might this affect flooding in Hazard City?
Choose from (1, 2, 3, 4)
1. Development can cause more water runoff into a stream and decrease the potential for flooding.
2. It would have no effect.
3. Development can cause more water runoff into a stream and increase the potential for flooding.
4. Development allows water to soak into the ground faster and decreases the potential for flooding downstream.
Insurance Cost Per Year for each $100,000 of property value* $301 Map Property Details Zone 7no one foot or more above base flood elevation Zone A Zone Aat base flood elevation $431 Zone A one foot or morv below base food one foot or more below base flood elevation $1251 Zone B no basement, previous flooding Zone Bbasement, previous flooding Zone B no basement, no previous flooding Zone B basement, no previous flooding Zone C no basement, previous flooding Zone Cbasement, previous flooding Zone C no basement, no previous flooding Zone C basement, no previous flooding Zone V Zone X no basement, previous flooding Zone Xbasement, previous flooding Zone X no basement, no previous flooding Zone X basement, no previous flooding $351 $441 $221 $246 $351 $441 $221 $246 $835 $351 $441 $221 $246 all properties (rates listed in this table are fictitious and do not represent actual insurance costs) insurance costs for a $200,000 home would be 2x the amount shown costs for a $50,000 home would be 0.5x the amountExplanation / Answer
Part A:
1 – Right, majority of riverside being located outside 100 year flood event are safer.
4- All of downtown is within zone C and safer from flooding this is due to the fact that most of the downtown lies outside 100 or 500 year flood event are safer.
Part B-
Part C-
Site 1: Site 1 lies in Zone A, and the condition applies one foot or more below base flood elevation so the applicable rate will be 1251 $
Site 2: Within zone B, Rate will apply for basement, previous flooding and will be 441 $
Site 3- Since the site lies in no basement no previous flooding the applicable rate would be 221 $
Part D:
Towards east (The elevation values decreases from west to east indicating the drop in elevation and direction of flow)
Part E: Answer 1
Urbanization leads to change in land use thereby creating impervious surface which may result in loss of infiltration and may cause localized flooding due to accumulation of water in ditches and small basins.
Part F: Answer 2 (Approximately 3 feet/mile)
Calculation:
Length of main river- approximately 1 miles
Drop in elevation- = = 841-838
= 3 feet
Gradient= 3 feet/1 mile
= 3 feet/mile
Part G: Answer 3
Explanation: Walnut height being the farthest community lying out of zone C and does not have any past recorded flooding event, hence will be at least risk of flooding.
Part H: Answer 3
Part I: Answer 4
If the Paluose river will be Dammed upstream, it will decrease the water level in Clearwater river and thus will result in less risk in Ralston.
Part J: Answer 3
The only explanation for occurrence of past flood deposits in the zones outside the ancient flood zones can be explained by shifting of the river channel from its course.
Part K: Answer 3
Flood insurance rate for property in zone B with no previous flooding and no basement is 221$ for 100,000 $ property value.
So for 250,000 $ property the rate would be:
=221*(250000/100000) $/ year
= 552.5 $ / year
Part L: Answer 3
South
Part M: Answer 3
Urbanization in upstream will lead to change in land use creation of impervious surface thereby resulting in increased flooding downstream.