How to build
a Whitewater Park
BoaterTalk Post • Video • Waller Creek Site •
Friends of the Falls
The best way to make
a whitewater feature - basically accelerate water
over a "slight" obstacle and "dump" it into still
water. The smaller the obstacle it jumps the
better. Too much rock and you get a hole.
link
Semi-circle 'U'-shaped rock pile to channel water
and create hole / eddies.
Whitewater Park Architecture and Science has
advanced dramatically.
Example of a "play wave" that
features can be modeled after.
Best
practices include:
Feasibility & Pre-design
Concept Development
Strategic Planning
Business Modeling
Limnology Studies & Habitat Design
Local, state, and federal permits
Venue Design
-Physical Modeling
-Computer Modeling
-In-stream Structures
-Boulder Placement
-Drop and Pool Structures
-Flow Hydraulics
-Flood Mitigation
-Water Safety
-Sediment Transport
-Target Species Habitat Restoration
Facilities Construction
Operations and Management
As far as creating a
play feature the only thing I can really offer up
is this. Play features are obviously in
places where either A. the gradient
increases and/or B. the velocity increases,
coupled with a few good rocks or ledges to kick
up or drop the water and form the play feature.
Remember that the flow (or volume of water moving
downstream) in a river is constant no matter
where you are on the run (obviously flows can
increase or decrease over time depending on rain
or dam releases). Even though you may be in
a still pool, the river is still pushing a
certain volume of water downstream. It just
may not be as noticeable at wider spots as it is
when the river chokes down in a gorge. Kind
of like a garden hose. You turn the water
on and you have a constant flow coming out of the
spigot. Placing your finger over the end
causes the water to come out faster even though
the flow (volume of water) is still the same
coming from the spout. The water must move
faster given the smaller cross sectional area.
In order to maintain the upstream pool and allow
for a play spot I would suggest something like a
weir. You already have the gradient and the
rocks to help form a feature. All you need
to do is concentrate the flow in one area to
increase the velocity of water traveling
downstream.
Q = Volume (ft^3/sec)
V = Velocity (ft/sec)
A = Area (ft^2)
Q = V*A
By decreasing the area (A) of water coming over
the dam, the river will have to increase the
velocity (V) of water to allow the same flow (Q)
to travel down the river. So instead of the
water pouring over the whole river wide dam,
arrange the rocks so that a smaller weir is
created which leads to a smaller cross sectional
area of water flowing through.
So in the equation, a smaller A results in a
larger V. Larger V means faster velocity
and wallah........play spot...sort of.
The broken down dam on the Benson is a classic
example of this concept. But I would think
the placement of rocks to actually form the
feature may be slightly more complex than that
and this is where an experienced whitewater
feature builder (not sure what their title would
be) would come into play.