# How much Rock?

Discussion in 'Water Features' started by Farbio, Jan 29, 2009.

1. ### FarbioLawnSite Memberfrom Washington StateMessages: 99

When you guys bid water features, how in the world do you estimate the correct amount of rock going in? I have no problem coming up with all the components needed for any water feature but I feel like I am just guessing on the rock. What procedures do you take to get a solid estimate on rock?

2. ### ANC Stone CreationsLawnSite Memberfrom Pacific Beach, WashingtonMessages: 160

It all depends on the size of the rock and also how much area you would like the rock to cover.

What size feature?
With or with out pond?
What size of rock for the pond edges and also the waterfalls?

3. ### STL Ponds and WaterfallsLawnSite Bronze Memberfrom St.louis MOMessages: 1,174

Also try to get to know your rock. Around here we use sandstone and granite. Granite is a lot more dense than sandstone and that can throw off you guesstimate of rock quanity. You can get an idea by using this formula LxW/65 for smaller type boulders and LxW/40 for ponds with bigger accent boulders. This is based on a 2ft deep pond and using a 1-2-1 ratio.

So if you do a 15x15 Pond with a smaller waterfall on edge of the pond you would need to use this formula.
15x15=225/65=3.5 tons So round up to 4 tons of boulders and get 1 ton of 6-12" boulders and 2 tons of 12-18" boulders and 1 ton of 18-24" boulders. Than add another ton for your waterfall depending on your type of waterfall. I hope this helps and doesn't confuse the hell out of you. There really isn't any precise way to order rock and be right on the money. The leftover rock can be used for accents if you have any.

4. ### FarbioLawnSite Memberfrom Washington StateMessages: 99

Hey thanks guys. I will try that formula on the first water feature this year and see how it comes out. There are two things I hate. First, bidding it for lets say 10 tons and have 3 ton sitting there to be hauled out when it is all said and done. Or, being short and having to eat profit by getting additional rock.

I know there isn't an exact science but would like to get closer.

5. ### ANC Stone CreationsLawnSite Memberfrom Pacific Beach, WashingtonMessages: 160

Farbio,

What part of Wa. are you from?

I do alot of work in Medina, Clyde Hill, Issaquah, Kirkland, Bellevue, Redmond and surrounding area.

Let me know if you have any questions.

6. ### ANC Stone CreationsLawnSite Memberfrom Pacific Beach, WashingtonMessages: 160

Farbio,

Have you ever used rock from AAA Diorite Quarry?
They have blueish grey basalt at awesome pricing.