Pond and Waterfall Calculations

Figuring out what you need to build your pond is an important factor to determine it’s cost and efficiency.  The following guidelines should help you. Ask for help at thepondpad@gmail.com

                          How to Estimate Gallon Capacity

Circular Pond: R2 x 3.14 x Depth x 7.48 = Approx. Gal. R2= Radius x Radius (Radius is ½ of the total length)

Irregular /Rectangular Pond: Length x Width x Ave. Depth x 7.48= Approx.Gal.

Irregular Pond w/shelves: Length x Width x Depth x 7.48 x .66= Approx. Gal.

Streams: Length x Width x .25 (Depth) x 7.48= Approx.Gal.

How to Calculate Pond Liner Size.

Length= Length + (Depth x 2) + 2      Width= Width + (Depth x 2) + 2

Example: 8 x 10, 2′ deep L= 10′ + (2×2) + 2= 16′ W= 8′ + (2×2) + 2= 15′ 

                                    Electrical Conversions / Consumption

WATTS= Volts x Amps AMPS= Watts / Volts 1HP= 745.7 Watts

Approximate Electrical Cost to run a pump, etc.

Amps x Volts x 1000 x .10(KW per hour) x 24hrs x 30.4 days=$ / month

                           Aquatic Plant Calculations

Water Lilies: 1 per every 45-60 Sq F

Marginal Plants: 1 plant per every 3′-4′ shelf margin

Bog Plants: 1 plant for every 2′ of bog


                            Rock Calculations- For Gravel & Boulders

Boulders for Pond Basin:

Length x Width / 65 Tons of Boulders Use a 1:2:1 ratio

For every 1 Ton of 6”-12” rock; get 2 Tons of 12”-18” and 1 Ton of 18”-24” rock

½ Ton of 6”-12” of rock will cover 20 linear feet

1 Ton of 12”-18” of rock will cover 10 linear feet

1 Ton of 18”-24” rock will cover 5 linear feet

Boulders for Stream– For every 10′ of Stream, Use 3/4 Tons of rock using ratio above.

Boulders for Waterfall– Use 1 Ton of rock per each 3′-4′. Choose some larger stones for support, and some rocks with flat or interesting faces for the waterfall.

Gravel for Pond Basin– Use 40% total tons used for pond boulders calculations

Gravel for Streams– Use ½ Ton for every 10′ of stream

Pondless/ Disapearring Waterfall– Length x Width x Depth = Cubic feet

Use 90lbs of rock per each cubic foot; Use Ratio of: 40% 4”-6” Rock

(for the bottom of the basin) and 60% of 1 1/2” – 2” rock (for middle and top layer). Add decorative gravel / rock as a top dress.

These are guidelines to help you, always over estimate whenever possible. Any left over rock can be blended into your surrounding landscape.

www.alpinegrows.com         www.thepondpad.com

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