Hoop house drainage & water supply

Lyndon Kelley MSU Extension / Purdue University Irrigation Management Agent

269-467–5511, cell 269-535-0343, kelleyl@msu.edu https://engineering.purdue.edu/ABE/Engagement/Irrigation

Proper drainage is essential •  The impermeable footprint of the tunnel roof creates a

concentration of rain (and snow) along the edges.

•  Having a slope, or shallow trench along the edges will help keep water from entering through the sides.

•  Aligning the long-axis on a very slight slope will also help with drainage and air movement. •  Six inch or greater height above surroundings >6”

Slight slope

Drainage is a concern of all hoop house construction.

Improving drainage •  Slope to open ditch •  Slope to Grass waterway •  Surface drain improved drainage

Improving drainage •  French Drain •  Collect or disperse

Raised beds hoop houses advantages: •  Soil warming: Raised beds provide the same soil warming benefits in a hoop house as in the

field. •  Best utilization of plastic mulch: Because beds are raised, mulch can be 'wrapped' around

soil profile ensuring a snug fit thus promoting efficient heat transfer. •  Ease of harvest: Beds elevate low growing crops reducing back stress during harvest. •  Effective soil solarization: Temperature in beds covered with 1-mil clear plastic mulch can

reach 140 degrees F at one inch depth. Six weeks of this treatment during the summer does an excellent job controlling soil borne pathogens. Closing the house increases the effectiveness of solarization.

•  Limited freeze protection: Heat radiating from beds moderates temperature around young transplants.

•  Site flexibility: Raised beds permit placement of hoop houses on sites with poor soil.

http://www.noble.org/ag/horticulture/hoophouse

https://www.leopold.iastate.edu/sites/default/files/pubs-and-papers/2012-01-rainwater-catchment-high-tunnel-irrigation-use.pdf

Collecting rainfall •  Side gutter •  Enclosed or lined drain

FarmTek

https://www.leopold.iastate.edu/pubs-and-papers/2012-01-rainwater-catchment-high-tunnel-irrigation-use

A 30’ x 64’ will displace 1200 gallons of water with a 1” rainfall

One inches of rain falling on a 1,000 square foot structure will generate about 600 gallons of rainwater!

1” of water on one square ft. of area = 0.6 of gallon

Annual rainfall 32”-36” Fall 3”- 4”/month Winter 2”- 3”/month Spring 3”- 4”/month Summer 2”- 3”/month

May require change in management

Rain water collection use: •  Tank sized to meet normal high use need for a week •  Jet pump or lift pump to deliver water to dispersal system •  An overflow to adequate drain •  Filter system to avoid plugging dispersal system •  Alternative water supply for when use is not met by rainfall •  Alternative clean water supply for when contamination builds to

unusable levels

Septic tank- about $1 / gallon

Underground storage tank •  Below surface making gravity (in) flow an option

from most sources •  Water temp cool to reduce bacterial growth •  Reduce freezing issues •  Pump needed to lift and pressurize water for use •  Require an overflow to adequate drain

Septic tank- about $1 / gallon

Storage tank size • 0.25” of Evapotranspiration /day is common (1.75”/week) • 0.30” of E.T. happen for a few days every summer (2.10”/week) • 0.25” of E.T./day = 1050 gallons of water need /1000 sq. ft./week • Eliminating sunlight reduce microbe growth • To reduce microbe and contamination issue avoid storing water more than 2 weeks • Design over flow to rotate stored water • Provide for drainage of over flow

1” of water on one square ft. of area = 0.6 of gallon

•  Sewage lift pumps to raised tank •  Sewage lift pumps with pressure regulator

•  Jet pumps with pressure tank

12 volt option Pressure

regulator

•  Requires screened intake pipe down into tank or screened bung at bottom of tank

•  Self draining option

A few reason to avoid water collection for irrigation: •  Unless you direct discharge rain water to a creek/ditch there is no

net savings of water to your water shed. •  Collected water has risk of plant pathogens •  Collected water has human health risk •  It is very hard to meet GAC requirements collected water •  Much greater filtering and cleaning requirement for drip system •  In most situations ground water is available in needed quantities •  Connection to existing water system or dedicated well is often

less expensive and more dependable.

Quantity Needed

Field Scale -Maximum water use for most crops is .27 - .32 in./day • 3 gal/minute/acre pump capacity = 1”/week • 5 gal/minute/acre pump capacity = .25 in./day • 7 gal/minute/acre pump capacity =.33 in./day, 1”every 3 days • 500 gal/minute pump can provide 1” every 4 days on 100 acres

Small Scale - Application time in hour for 1000 ft. sq. Gallons /minute

Hour  to  apply  1"on  1000  /.  sq.  

Hour to apply 0.25"on  1000 ft. sq.

Hour to apply  0.10"on  1000 ft. sq.

1   10.39   2.60   1.04  

2   5.19   1.30   0.52  

3   3.46   0.87   0.35  

4   2.60   0.65   0.26  

5   2.08   0.52   0.21  

6   1.73   0.43   0.17  

7   1.48   0.37   0.15  

8   1.30   0.32   0.13  

9   1.15   0.29   0.12  10   1.04   0.26   0.10  

1” on 1000 ft. sq. = 623 gallons

Private Water Systems Handbook Contents: Planning for Water Use Water Sources: Wells Maintaining Pressure in a Private Water System Water Distribution Water Quality and Testing Water Treatment Water Protection Water Systems Maintenance Calendar Pumps Collection and Storage: Catchments, Cisterns, Ponds, and Springs

http://mtngrv.missouristate.edu/Publications/Drip_Irrigation_&_Watering_Web_Links.pdf Trickle Irrigation in the Eastern United States NRAES-4, $6

•  Frost Free Water Hydrants •  Vacuum breaker •  Self draining manifold or

manual drain

•  Frost Free Water Hydrants •  Vacuum breaker •  Temporary hose •  Be careful of hose end chemical applicator

•  Winter water use is minimal •  Most water use will be in warm spells

?? unless you are watering to build heat

Home wells are expensive, undependable, inefficient irrigation water source if ran

continuously

If you must: •  Isolate the home •  Install a continues use pump •  Consider a variable frequency drive •  Will it require backflow protection? RPZ ? •  Consider an accumulation tank

A dedicated Irrigation well maybe a good investment.