# Presentation: 947335

## DAMS & DIKES/LEVEES

**JACK FORRISTEL**

## 1.2M Square miles

- 1.2M **Square** miles

**(CA is 158,647 Square miles)**

## Santa Clara Valley Watershed

- 5 individual watersheds
- 10 reservoirs
- 168,914 af storage capacity
- 3.7% of Shasta
- 0.6% of Lake Mead

## Headwaters Of The Mississippi RiverLake Itaska, Minnesota

## The RiverEnd To End

- 2,341 mi long
- 3rd largest in world
- One drop takes 90 days to reach the Gulf
- Flow is 1.2 mph at source and 3 mph at mouth
- 1,475 elevation drop from top to bottom

## MississippiDelta

- 7,000 years to create. 80 years to control.
- Note channel which has “meandered” over the years.
- 5.5 MGPS (= 46’ deep x 1228” long x 230’ wide pools every second).
- 160M Tons of sediment per year exit the delta and is deposited beyond the continental shelf.

## Interesting Facts

- 1927 floods covered 27,000 sq mi, caused 200 deaths and displaced 600,000 people.
- Congress mandated Corp Of Engineers to control flooding and enhance navigation.  Dams and dikes/levees followed.
- At New Orleans, river is 1/2 mile wide and 200 ft deep.
- Total system has 12,300 miles of waterways.
- River is navigable to Minneapolis-St. Paul.
- Opened central US to foreign markets and provided competitive/economical transportation system.
- Carries 160,000,000 tons of sediment per year to the Gulf.  Most flows over the continental shelf to deep water rather than being dispersed and deposited within the wet-lands.

## Dams On Upper River

- 29 dams on upper river control depth to 9 ft min
- Specifically installed to aid navigation - not flood control
- During floods, gates are opened
- Each dam has locks attached
- Tributaries have dams to control flooding & aid navigation

## Reasons For Damming

- Bonneville Dam, Oregon
-        ***Flood Control***

-     Mississippi River
-         ***Navigation***

## Reasons For Damming

-             Almaden
***Community Water-Recreation***

-            Hetch Hetchy
***        ******Community Water (Only)***

## Reasons For Damming

- Shasta Dam      Hydroelectric Generation

## Negative Impacts of Dams & Levees

- •  *Fisheries may be interrupted by interfering with spawning and water temperatures changes.*

- •  Takes away land from other uses

- •  *Potential for precluding archeological research*

- •  Detract from natural setting

- •  *Increased evaporation of surface water*

- •  Silting effects all dams

- •  *Other you may think of*

## Slide 13

## Slide 14

## Slide 15

## Slide 16

## Levee Types

***Mainline & Tributary*** Levee:  Parallels main channel
***Ring*** Levee:  Encircles an area
***Setback*** Levee:  Backup to existing levee
***Sub*** Levee:  Control under seepage
***Spur*** Levee:  Protects main levee by directing current riverward

## Levee Construction

## Levees

- Mississippi River has 1,602 miles of 25 ft high levees
- Sacramento Delta has 1,100 miles of 20 ft high levees controlling flow or isolating land from five rivers: Sacramento - San Joaquin - Mukelumne - Cosumnes - Calaveras
- 47% of states total water runoff flows through the Sacramento Delta
- South Bay has many miles of very low levees which isolate the evaporation ponds

## Commerce

- 12 rivers support the commerce of the river system. They are the Ohio, Missouri, Illinois, Arkansas, Tennessee, Cumberland, Green/Baren, Konawha, Kentucky, Monongahela, Allegheny, Clinch.
- Total system contains 12,300 miles of waterways.
- Generates $284B annually to the economy.
- New Orleans is largest grain port in the world.
- Grains, coal, coke, petroleum products, sand, gravel, salt sulphur, chemicals and others.

## Transportation

- Integrated tows can be composed of 40 or more 1,000T barges carrying 200,000 barrels of petroleum.  An average though would be 15 barges which is equal to a 3 mile long train or 34 miles of 18 wheelers.
- Between 31 July and 12 August there were 636 barges within the system.  321 were traveling upstream while 315 were going down stream.

## Slide 22

## JTO Dam Demonstration

- Very poor description in the teachers edition.
- From others, try 6 Fettucine, 12 Spaghetti, 3/8 C flour & 1 tsp Salt.
- Objective is to test strength of various types at constant elevation
- Let imaginations run wild