Large Pump Canyon Extension [PB1977]

Large Pump Canyon Extension

Need more underground water storage for your pond-less waterfall, but don't have room for a wider reservoir? The Blue Thumb Large Pump Canyon Extension (PB1977) lets you build a deeper basin while maintaining a compact footprint. Designed specifically for the Large Elite Pump Canyon, this 48-inch extension offers multiple cut-to-size measurements to help accommodate different reservoir depths.

A deeper lined reservoir can provide additional water capacity for a pond-less waterfall system without requiring the same increase in surface area.

Four published cut measurements give installers flexibility when planning the extension height for the excavation and reservoir configuration.

Made to pair with Blue Thumb's Large Elite Pump Canyon, helping expand the design possibilities of a compatible underground waterfall basin.

Before ordering, confirm which Blue Thumb Pump Canyon you own. The Large and Small extensions are different products and should not be treated as interchangeable.

SKU: PB1977 Height: 48" Fits: Large Elite Pump Canyon

Designed for deeper large-system reservoir applications.

The smaller extension is intended for the Small Pump Canyon instead.

The extension has an overall height of 48 inches. Blue Thumb lists four cut measurements: 9.5", 18.75", 27.5", and 38" , measured from the extension's top lip.

Determine the appropriate finished configuration before cutting. These numbers describe cut measurements, not four different product sizes or four separate included extensions.

The manufacturer's catalog lists a maximum basin depth of 78 inches for the Large extension system. Actual excavation and reservoir design must account for the installed components, liner, site conditions, and required water capacity.

PB1977 is the Large Pump Canyon Extension . It is an expansion component for a compatible Pump Canyon system, not a complete pond-less waterfall kit.

Depending on your installation, other components include:

Basin Matrix water-storage modules

Properly sized reservoir liner and protective underlayment

Pump, discharge assembly, plumbing, and waterfall spillway

The extension allows more depth, but a successful reservoir also depends on adequate water storage, suitable matrix layout, proper liner installation, and continued access to the pump.

Determine the water-storage needs of the waterfall and choose an excavation layout suited to the Pump Canyon, Basin Matrix, and site conditions.

Review the four published cut measurements and confirm the required assembled height before making permanent cuts.

Excavate to the planned dimensions, remove sharp objects, and install the protective underliner and rubber basin liner following the applicable installation instructions.

Fit the extension into the compatible Pump Canyon configuration, position the reservoir components, and maintain access for future pump maintenance.

Finish the basin and plumbing according to the system instructions. Fill and test the waterfall while checking operating water levels and all connections.

A deeper reservoir still requires regular water-level monitoring. Evaporation and splash loss can lower the water level over time, and a pump should never be allowed to operate without sufficient water.

Keep the Pump Canyon accessible for inspection, remove debris from the waterfall and streambed, and follow Blue Thumb's seasonal maintenance recommendations. An optional automatic water fill system can reduce manual topping off when properly installed.

Use these official Blue Thumb guides to plan the complete waterfall system and maintain it after installation.

This official Blue Thumb video demonstrates the installation process for a pond-less waterfall kit, including reservoir excavation, pump and plumbing setup, and finishing the waterfall.

Official Blue Thumb pond-less waterfall installation overview. This video illustrates the general system rather than the exact PB1977 Large Pump Canyon Extension. Extension components and other equipment may be sold separately.

Not sure how deep your basin should be, how much water storage you need, or whether this extension fits your project? Blue Thumb's Sales & Tech Team can help you review your pond-less waterfall design.

The extension has an overall height of 48 inches before any cutting.

Blue Thumb lists cut measurements of 9.5", 18.75", 27.5", and 38". Each is measured from the top lip of the extension. Confirm the required finished height and cutting instructions before trimming.

A deeper basin can increase available water-storage capacity, but actual capacity depends on excavation dimensions, liner configuration, matrix layout, and the space occupied by installed components.

No. This is a reservoir extension only. A complete waterfall system also requires an appropriate Pump Canyon, liner, water-storage components, pump, plumbing, and spillway.

Blue Thumb provides official Elite Cascading Falls installation instructions, Pump Canyon instructions, and a pond-less waterfall maintenance guide in the Product Resources section above. For extension-specific cutting or assembly questions, contact the Sales & Tech Team.