The Lake

Trinity Ski Park

Dallas
Texas

The Lake

Fishtrap Lake

The lake that we have studied in West Dallas is Fishtrap Lake. Fishtrap Lake is a constant level lake that is fed by surface runoff. According to DHA, who owns the lake, the lake is 6.5 feet deep on average. Our consultants have verified that the surface elevation is at 403 feet and the banks are at 410 feet.

The North Texas Council of Governments ("NTCOG") is the state designated water quality management planning agency for the urbanized portion of Dallas-Fort Worth. Here is a link to NCTCOG's website that describes their role in this process,

http://www.nctcog.org/envir/SEEclean/stormwater/index.asp

As part of their duties, NTCOG has tested stormwater in this area of West Dallas. The most recent test was done in 2008, the results of that test can also be found online:

http://www.nctcog.org/envir/SEEclean/stormwater/program-areas/monitoring/data/stationdetails.asp?Station=DL0802

During heavy rains, the water drains from Fishtrap Lake to a smaller lake that borders Kingbridge Park across the street from Fishtrap Park. The elevation of that lake is approximately 396 feet or 7 feet lower than Fishtrap Lake. Ultimately the water flows to the old West Fork of the Trinity River to the sump station located at Canada Drive and Holystone. From there, the water flows through the levees to the Trinity River.

In order to improve the water quality at Fishtrap Lake, we propose aerating the lake with fountains. That will pump oxygen into the lake which will improve the aquatic life and recreational use of the lake.

Cableways insure a high oxygen supply is delivered into the water. Between fallen riders swimming to shore and the intense water movement created by riders breaking the surface as they cruise around the lake, manufacturers estimate an oxygen supply of five tons per year is delivered into the local water. This creates excellent water quality for fish and other wildlife. Cable systems also emit no harmful emissions. No boats, no fumes, no noise.

Limited Power Consumption

It doesn’t take a lot of power to run a cable park. Sesitec estimates that their electric drives only consume an average of 10kW per operation hour. To put this in perspective, it takes an average of 5 kW of power to dry one load of laundry. A cable system can operate for less than $10 per day (depending on the cost of electricity in your area). And since the amount of electricity you use is so small, we could possibly afford to purchase a renewable energy source, such as 100% clean wind, to power the cable system.

System Description

General
A cable system can be built as a 4, 5 or 6 cornered cableway with single lateral lengths of maximum 1033 foot (315 meters). The depth of water should be higher than 4 foot (1.2 meters) in its cruising radius. The two main running cables which are connected through the carriers run over a pair of horizontal installed aluminum spoke wheels. The drive, including all necessary elements (infinitely variable speed regulation between 0 mph (km/h) and 38 mph (62 km/h)) is installed at the cantilever of the pylon, which is next to the starting point. At a different pylon the stirrup is held by a rigging device for counterweight. The remaining pylons each have one cantilever which keeps the stirrup. All pylons and cantilevers are held by rigging cables. Due to the right-angled starting principle the waterskier / wakeboarder can be coupled in with a very smooth acceleration at all driven speeds.

Pylons, Cantilever
The pylons and cantilevers of triangular steel lattice construction tower between 33 to 40 foot (10 to 12 meters) above the watersurface. They are held through anchors and rigging cables in its necessary position. Due to the fact that the whole system merely causes pure pressure force in the pylon, a footplate of 1,2 yd² (1 m²) size , which sits on the waterground or shore, is sufficient.

Anchors
According to the local circumstances the concrete anchors can be placed either on the waterground or can be concreted at the shore into the ground.

Pendant Ropes
The pendant ropes have to keep the pylons and cantilevers in their position. They also take up the forces which are caused by the main running cables.

Wheels, Axles, Connecting Head
The aluminum spoke wheels are seated on bearing supported axles. All wheels have a plastic lining. Axles are attached to the cantilever through the connecting heads.

Drive; Control
The main running cables are powered by a frequency regulated electric motor. All required processes of operation and control can be made either from the operating stand or from the maintenance platform at the drive.

Running Cables
Using a pair of running cables, made from a special, almost non rotating running cable, secure waterskiing is guaranteed not only at high speed but also under the strong stress of the skier.

Breaks
In case of emergency the main running cables can be immediately stopped through a disk break.

Operation

Coupling
To get a waterskier/wakeboarder started the operator only has to push a button on the switch panel. A pneumatic cylinder makes sure that the rope will engage into the next coming carrier.

Decoupling
After finishing his turn the rope can be uncoupled by a pneumatic controlled catch fork just by pushing one button.

Speed Variation
Speed can be adjusted either through a infinitely potentiometer or various adjustable fixed speed buttons. The current speed can be seen at the Speedo.