For aquapark items it is helpful to think in terms of mooring rather than anchoring. Aquapark items are large and can move a lot even in a light breeze. It is important to keep items in place to ensure swimmers reach them safely. Therefore, we recommend using a 1:1 ratio of anchor line to depth ratio and a flexible heavy duty braided bungie to give some flexibility for waves and water level changes. We also recommend heavy weighted mooring blocks, ground screws or earth anchors.
Weighted mooring blocks can be sourced from dock and mooring professionals in your region or homemade by you using built or purchased forms. Sonotube makes an excellent pre-fabricated form system that contains no harmful chemicals and is biodegradable. Sonotubes are widely available - you can contact Sonotube’s customer service at 888-766-8823 to find the nearest distributor. Some prefer to make their own forms using a wooden grid, old car tires, or 50-gallon barrels. Home poured moorings typically use bent rebar (omega-shaped) or metal anchor eyes to reinforce them and make an attachment point.
Poured concrete weighs 4050 lbs. / cubic yard. In metric terms 1837 kg / 765 L, or 2.4 kg / 1 Liter. Some weighted anchor examples:
- 30” diameter Sonotube w/ poured concrete; 30” x 9” = 551.7 lbs. (250 kg)
- 30” diameter Sonotube w/ poured concrete; 30” x 18” = 1103 lbs. (500 kg)
- Square block w/ poured concrete, 24” x 24” x 18” = 900 lbs. (408 kg)
- Square block w/ poured concrete, 24” x 24” x 24” = 1200 lbs. (544 kg)
- 50-Gallon barrel w/ poured concrete = 1166 lbs. (529 kg)
Mooring blocks made with Sonotube forms and rebar:
Mooring blocks made with wooden forms and rebar:
For DIY mooring blocks, requesting leftover concrete from construction pours or self-mix concrete bags are simple ways to save cost. Several smaller blocks can be lashed together with chain, which are easier to move, but may require a diver.
In areas with dense silt or sand and no rocks, ground screws can be installed to achieve similar holding strength. This option typically requires a diver.
Professional earth anchor systems such as Platipus can also be used in most any situation to achieve adequate holding strength. These systems can be professionally installed by earth anchor contractors or by DIY, and may require a diver.