New effluent storage tank

Councils’ and Fonterra’s ‘effluent storage calculator’ allows for cow numbers, soil types and weather patterns, to show farmers what storage capacity they need. 

Graeme ‘Grimmy’ and Sharon Martin, who own three farms within 10km of Morrinsville, were facing, on one farm, the limit of its effluent storage capacity with  effluent being pumped directly to pasture.

“We had been considering upgrading our effluent system for a while on one farm which is 50% peat and 50% Tauhei clay, and after discussion with the Fonterra sustainability team we decided to install an above-ground Kliptank,” said Sharon.

Installation required placing a 600mm deep, level pad of dry peat on top of the ground, compacting it with a tractor and erecting the Kliptank directly on this. The tank, situated 45m from the dairy, holds 655,330L in a liner 75 microns thick. 

It measures 2m high x 22m diameter. 

Kliptank’s North Island sales manager David Parker told Dairy News the tank is 385m2 in area and weighs 655t when full. “This exerts ground pressure of 2.4psi. For comparison, a 90kg person with a size-10 shoe exerts 11psi ground pressure; a utility truck exerts 25psi, so there is no worry about the Kliptank sinking.” 

Sharon estimates it has 60 days capacity. The tank was erected in two days; the liner installed in one.

Martins have upgraded their entire effluent handling system. Now the material passes from the yard through a stone trap to a 15000L holding tank. If an emergency prevents pumping the tank can hold effluent from two milkings. 

It has a 3.7kW pump with float switch, and a 1.1kW stirrer. The stirrer starts two minutes before the pump, emptying the sump daily to the Kliptank. Covering all eventualities, if this holding tank overflows the material will be directed to another sump for pumping direct to the Kliptank.

The storage tank has a stirrer on a floating pontoon operated by a manual switch. The outlet is at the bottom of the tank. 

A Rovatti 15hp pump shifts the effluent around the farm via three lines and a travelling irrigator. The lines have snap couplings.

Sharon reckons running a 2 x 140-cow split herd has lessened effluent on the yard. “With 140 head, 40 are immediately in the shed and the rest are only on the yard for a short time.” 

The Martins acknowledge the whole system must be well managed, with the correct procedures in place for spraying at the correct time.

“We will operate the pumps and irrigator manually and when
we see fine weather ahead we’ll do as many
paddocks as possible,
aiming to have no ponding or run-off,” says
Grimmy.

Tel. 0800 255 222

www.kliptank.com