Created By:

Nick Sianta

Luqi Shan

Ryan Silkworth

CIVE401 Fall 2014

Sluice Gates

What is it?

A sluice gate is a piece of hydraulic machinery that

is used to regulate discharge and flow depth in an

open channel such as a river, canal, or ditch. The

term “sluice” refers to a man-made channel or

modified natural channel that conducts water

(Phillips). Sluice gates began to surface with the

increasing popularity in mills. Millers needed a

way to regulate flow down sluices to power their

waterwheels, opening the door for the

implementation of sluice gates (Phillips). In

today’s world, sluice gates are found in a wide

variety of applications; mines, water treatment facilities, agriculture, dams, and many more.

Types of Sluice Gates

There are two main types of sluices gates; those that

move vertically, and those that act as a flap. The

former is the most popular and widely used. In most

applications, the sluice gate starts with its bottom

edge along the bottom of the channel. This acts as a

barrier, not allowing any flow through. When the

sluice gate is raised, fluid moves from the holding

area, under the gate, and down the channel. The

gate can be raised and lowered in a number of ways

depending on the application; in high pressure

situations, such as for use in dams, hydraulic

systems are used. However, for smaller scale uses,

sluice gates may be raised and lowered manually or

by an electrically-driven hoisting system (Phillips).

A very important part to the effective use of a vertical sluice gate is the seal and sliding

mechanism. When the gate is submerged to the bottom of the channel, it must have a watertight

seal at the gate-slide interface. As the gate is raised or lowered, it moves relative to ball bearings

or a slide-track, and it is essential to the function of the gate that these components be kept dry to

prevent corrosion. Some vertically moving sluice gates can also be used as a sharp-crested weir

if they are submerged under the surface level of the flow.

The other type of sluice gate acts as a flap when the water pressure on one side becomes greater

than the other. The operation of this type of sluice gate is a result of the hydrostatic distribution

on pressure. As the water level on one side of the flap increases, the pressure on that side of the

flap increases. Additionally, the center of the pressure on the flap moves further down the flap,

generating a larger torque about the hinge, which is typically located at the top of the flap. Flap

sluice gates are designed such that at a certain water level, the pressure felt by the flap will reach

a threshold pressure, allowing the gate to rotate about its hinge, letting flow in from under it.

Figure 1 – A typical metal sluice gate

Figure 2 – A wooden sluice gate

Whether a traditional vertical or flap sluice gate, the gates are typically made from wood or

metal. In today’s world, most applications call for a sluice gate made of non-corrosive metal to

meet strength and durability requirements. However, many agricultural applications still employ

wooden sluice gates.

Historical Example: Yuma Project

At the beginning of the 20th

century, farmers in

Arizona and California needed a way to take

advantage of year-round growing conditions to

meet increasing population needs. The answer was

the Yuma Project, created by the U.S. Bureau of

Reclamation in 1904 to deliver water from the

Colorado River to farmers in the area. The Laguna

Dam was the original main feature of this project,

which employed a very large sluice gate (Figure 4)

to control flows. The Laguna Dam was put out of

commission in 1948; however the sluiceway is still

in commission to regulate flows for agricultural use

(USBR).

Theory

Figure 4 – Schematic of flow under a sluice gate

The following analysis will be performed for a rectangular channel, the most frequent cross-

section encountered in sluice gate design. The unit discharge, q, is defined as the flow per unit

width. The flow starts at upstream depth y1, passes under the sluice gate at depth w, and flows

out at depth y2 due to the vena contracta effect. If the specific energy, E, defined as:

is assumed to be constant in the control volume (i.e. no losses), then the unit flow rate under the

gate becomes only a function of the upstream depth and the gate depth. After a mild derivation,

the unit flow rate can be described as:

y1 q

w

Figure 3 – Sluice gate at the Laguna Dam

where Cd is the discharge coefficient (roughly equal to 0.6 in practice). The flow is subcritical

upstream and supercritical downstream.

If an obstruction is placed far downstream of sluice gate, it can cause a natural phenomenon

know as a hydraulic jump. The obstruction causes the flow far downstream to rise to a subcritical

depths. In order for the supercritical flow immediately out of the sluice gate to convert to the

subcritical level, the flow undergoes a turbulent step-up where energy is lost. Figure 6

demonstrates this process

The upstream and downstream depths of the hydraulic jump, y2 and y3, are related to one another

by the Froude Number of the upstream depth:

The energy loss across the jump can be described by:

Hydraulic jumps are often designed for in engineering practice for different applications. A main

use is for sediment transport and erosion control. By designing hydraulic jumps in controlled

locations, sediment can be collected and controlled. This also reduces the velocity downstream

of the jump, preventing erosion. Hydraulic jumps are also engineered for mixing applications.

The turbulent nature of the jump causes large eddies that do a good job of mixing chemicals and

other additives.

y1

w

y2

y3

Figure 5 – Schematic of a sluice gate with a hydraulic jump

Tainter Gates

What is it?

A Tainter gate (also known as a

radial gate) is used in locks, dams, and

spillways to regulate water flow and

control water depth. The gate face is

curved with an arc facing upstream.

This is connected to an arm which is

rotated around a pivot point to control

the gate’s position. Some Tainter gates

have a balance mass at the opposite end

arm end to facilitate opening or closing.

Tainter gates and Sluice gates have the

same basic hydraulic principles, though

due to the long arm and rounded face

less energy is required to open and

close a similar sized Tainter gate.

Therefore, they are ideal for situations where the gate must be large or heavy or when there is a

limit on available force to open or close the gate. When the gate it submerged the pressure forces

act perpendicular to the gate’s surface. Engineers design the arm length and the gate curvature

such that all pressure forces will act through the pivot point.

Historical Example

The Tainter gate is named for Jeremiah

Burnham Tainter who first utilized the concept in

the West. The Red Cedar River Company was

looking for a way to pass runs of floating lumber

past dam sights on their way to market. Tainter

was tasked with creating a control device which

could quickly release water and floating lumber

downstream. His solution, the radial gate, was first

implemented at the Menomonie Dam in

Wisconsin. The design was particularly successful

because the results was a lightweight, economical

gate which can be opened and closed quickly with minimal force and displacement requirements.

Figure 6 – Tainter Gate Design Drawing

Figure 7 - 3D CAD Drawing of a Tainter Gate

Gate Configuration

Today Tainter gates are widely used across the world in both small scale and large scale

water control projects. The gates are installed in one of two fashions based on the need. The first

known as an overflow gate is designed such that water could flow over the top of a closed gate

under the right circumstances. These gates are designed for a certain safe overflow level. The

other type utilizes a breastwall, a vertical concrete wall above the closed state gate, which allows

additional up stream storage capacity. This design requires a strong seals which remain in

constant contact with the curved gate surface and often silt and debris are problematic for gates

in this setup.

Field Example - Upper Mississippi River Stairway

The Mississippi River has long been a key

transportation route however; navigation was

largely subjected to diverse seasonal

conditions. The Mississippi flows deep and

dangerously turbulent in flooding months, but

slow and impassibly shallow during draught

months. The river is overlaid with sudden and

treacherous rapids, submerged rocks,

uncharted sand bars and underwater plants,

which made traveling the Mississippi

dangerous in the nineteenth century. In 1930

Congress passed legislation which aimed at

providing a navigation channel with a

minimum 9 foot depth across 400 feet from

Minneapolis St. Paul to St. Louis.

Figure 8 - Whatcom Lake Dam

Figure 9 - Dam No. 8 (1936)

Figure 10 - Tainter Gate

Figure 11 – Cross section of Mississippi River from Minneapolis to St. Louis

The product is a series of 29 lock and dams which

separate the river into “pools.” Each pool has a

narrow operating range dictated by law with

specific lower and upper operational limits, which

helps maintains a nine foot navigation channel.

The lock and dams create a series of steps which

barges and other boats utilized the lock to either

climb or descend to travel upstream or

downstream. These lock and dam structures are

not designed to mitigate flood conditions. Though

they appear to be large flood control structures like

a reservoir, locks and dams do not store water; they cannot prevent or cause flooding and they

have no flood control capabilities (USACE). If dams could hold back or store water, the pool

created behind the dam would be so enormous that it would flood many communities (USACE).

Many of the lock and dams on the Mississippi utilize both Tainter and roller gates. The roller

gates help allay erosion and are typically placed in the center of the dams to help maintain the

nine foot navigation channel while the cheaper and more efficient Tainter gates are utilized on

either ends of the dams.

Hydrodynamic Principles

Tainter gates and Sluice gates have the same

basic hydraulic principles. In short they both act as

orifices and therefore can be analyzed similarly, as

shown below.

Figure 12 - Barge Passing Through McAlpine Lock and Dam in Louisville

Figure 13 - Lock and Dam 10 Guttenberg, Iowa

Roller Gates

What is it?

Roller gates are one of the most common

floodgates designed to control water flow and set

spillway crest heights in dams. This kind of

gates is a large cylinder that moves in an angled

slow, hoisted with a chain and have a cogged

design that interfaces with their slot

(“Floodgate”). With these, lifting and lowering

of the gate can be accomplished to alter

elevation and thus controlling the flow from one

pool to another. To lower the gate, the lifting

chain is let out and the gate rolls down the

inclined rack into the river. Openings in the gate

skin plate let water in so that it will not be buoyant (Greimann, Stecker, Kraal and Foltz 5).

Historical Example: Rock Island Dam

Rock Island Dam and Hydro Project had been built from

1929 to 1933, being the first dam to span the Columbia

(“Rock Island Dam”). As industry and agriculture increased,

deeper and wider navigational channels were under demands

in old days. People came up with the idea of building locks

and dams to make the river level higher. Rock Island Dam

was one of these dams constructed in 1932. It only used

roller gates to restrict the river and decrease erosion. The two

end gates are always kept slightly raised to ensure good water

motion (Oestreich).

Main Components Descriptions and Types of Roller

Gates

It is necessary to get to know how the structure of a

roller gate looks like and how the functions related to

the design. Followings are identifications of main

components in a roller gate.

The lower apron is a no cylindrical portion of the

gate. It helps preventing flow to go under the roller

gate. The bottom seal is the interface between the

lower apron and the concrete sill. When the gate is set

lowered, it lies on the concrete sill and hold back the

water. When raised, it can let water run beneath it.

There is a lifting chain connecting the operation

system and the gate to make raise and lower two

Figure 14 – A roller gate

Figure 15 – Rock Island Dam

Figure 16 – Single-apron non submersible roller gate

positions available.

There are typically two types of roller gates. One is non-submersible, which is raised above the

water surface and makes the river run beneath the gate without touching. The other is thought to

be submersible. It can be dropped under the water surface and allow the storm to run over them.

The first roller gates on the Upper Mississippi were non-

submersible. For non-submersible roller gates, they lowered

against the sill to form a bottom seal. Since they have massive

construction, operating machinery and their ability to be raised,

this kind of roller gates are considered to be valuable (O’ Brien,

Rathbun and O’Bannon). Later, another type of roller gates were

produced, which thought to be an improvement over the first one

since they allowed for the almost unobstructed flow of

floodwater, ice and debris (O’ Brien, Rathbun and O’Bannon).

The new type gates have two sill levels: a high upstream level

and a low downstream level, which were combined by a curved

section of concrete.

Equations of Discharge

From Collins (1977), for submerged-orifice flow

regime, theoretical equation of discharge:

Q =

when and or and

Where Q = discharge, = submerged-orifice flow

coefficient of discharge, static-headwater depth,

static-tailwater depth, vertical hight of

roller gate opening, B = roller gate width, g = gravity

acceleration, = static head differential ( ).

From a project operated by U.S. Army Corps of

Engineers conducted on Lock and Dam No. 7 (Corsi

and Schuler 1995),

= 0.78

when orifice-submergence ratio 1.5 <

< 12.4,

= 1.4

when orifice-submergence ratio 1.3 <

< 1.5.

Then, Q = 0.78 B

when 1.5 <

< 12.4,

Q = 1.4 B

when 1.3 <

< 1.5.

Figure 17 – Double-apron submersible roller gate

Figure 18 – Sectional view of a roller gate

Works Cited

Collins, D.L., 1977, Computation of records of stream flow at control structures: U.S. Geological

Survey Water-Resources Investigations 77-8, p. 2-3. 13 Nov. 2014.

Corsi, S.R. and Schuler, J.G., 1995, Discharge ratings for tainter gates and roller gates at lock

and dam no.7 on the Mississippi river, LA Crescent, Minnesota: U.S. Geological Survey

Water-Resources Investigations 95-4089, p. 13. 13 Nov. 2014.

O'Brien, William Patrick, Mary Yearter Rathbun, and Patrick O'Bannon. "Gateways to

Commerce." National Parks Service. U.S. Department of the Interior, 1 Feb. 2008. Web.

13 Nov. 2014.

Oestreich, Diane. “Rock Island Preservation Society.” Ockislandpreservation.org.

Ockislandpreservation.org. Feb 2013. Web. 13 Nov. 2014.

Phillips, Heather, and Michelle Arevalo. "What Is a Sluice Gate?" WiseGeek. Conjecture, 06

Nov. 2014. Web. 17 Oct. 2014.

"Project Details - Yuma Project - Bureau of Reclamation." Project Details - Yuma Project -

Bureau of Reclamation. United States Bureau of Reclamation, n.d. Web. 17 Oct. 2014.

“Rock Island Dam.” Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc. 6 Nov,

2014. Web. 13 Nov. 2014.

Photo Credits:

Figure 1: http://news.genius.com/1873919/Patton-oswalt-a-closed-letter-to-myself-about-

thievery-heckling-and-rape-jokes/Sluice-gate

Figure 2: http://www.panoramio.com/photo/27189926

Figure 3: http://www.usbr.gov/projects/Project.jsp?proj_Name=Yuma+Project

Figure 4: http://en.wikipedia.org/wiki/Energy%E2%80%93depth_relationship_i

n_a_rectangular_channel

Figure 5: http://www.chegg.com/homework-help/figure-c106-shows-horizontal-flow-water-

sluice-gate-hydrauli-chapter-10-problem-6cp-solution-9780073529349-exc

Figure 6: http://www.ivorbittle.co.uk/Books/Fluids%20book/Chapter%2010%20web%20docs/

Figure 7: http://grabcad.com/library/tainter-gate-radial-gate-1

Figure 8: http://www.ecy.wa.gov/programs/wr/dams/pp_ThreeTainterGates.html

Figure 9: National Archives and Records Administration

Figure 10: http://www.kleinschmidtgroup.com/service-areas/hydroelectric-engineering-

hydropower-engineering-consultants/dam-and-spillway-engineering/gates/

Figure 11: http://rivercitiescondos.com/cruising/region1.html

Figure 12: http://badwaterjournal.com/Bad_Water_Journal/Loop.html

Figure 13: http://42n.blogspot.com/2011_08_01_archive.html

Figure 14: Weeks, John A., Iii. "Coon Rapids Dam, Coon Rapids, MN." Coon Rapids Dam,

Coon Rapids, MN. N.p., 2008. Web. 13 Nov. 2014.

Figure 15:

http://en.wikipedia.org/wiki/Rock_Island_Dam#mediaviewer/File:ROCK_ISLAND_DA

M_IS_THE_OLDEST_DAM_ON_THE_COLUMBIA_RIVER_-_NARA_-_548012.jpg

Figure 16: http://acwc.sdp.sirsi.net/client/search/asset/1004750

Figure 17: http://acwc.sdp.sirsi.net/client/search/asset/1004750

Figure 18: http://pubs.usgs.gov/wri/1995/4089/report.pdf

Sources for Tainter Gate Section

“Radial (Tainter) Gates,” Hydro Gates Company, Denver, CO. Available:

http://www.hydrogate.com/products/literature/Radial%20Gates.pdf

“The Tainter Gate”, Dunn County Historical Society Available:

http://www.dunnhistory.org/history/exgate.html

“Why do we have lock and dams?” US Army Corps of Engineer. Available:

http://www2.mvr.usace.army.mil/FullStory.cfm?ID=1072