farm water managementcrkeyline.ca/.../2016/12/farm-water-management-.pdf · on small farms in our...

!Farm Water Management Slow, Sink, Spread, Store & Plan for Overflow

Nov. 28, 2016 Tayler Krawczyk Hatchet & Seed

www.hatchetnseed.ca

Hatchet & SeedEdible Landscapes + Eco-Design

Funding by:

Supported by:

Take Home Lessons for Today

! Slow – reduce velocity of storm runoff, reduce erosion, protect rivers/streams from dangerous swelling

! Spread - use gravity to move water from wet areas (valleys) to dry areas (ridges)

! Sink – increase infiltration & percolation, increase ‘interflow’, increase groundwater recharge

! Store – hold water in retention basins, dugouts, ponds reservoirs and in high OM soil for later use

! Plan for Overflow – plan where where record storm-water surges will go, don’t be surprised

www.hatchetnseed.ca


“We can stabilize climate [store carbon, and restore watershed function] as a by-product of profitable, ecological farming.”

- Abe Collins, Holistic Planned Grazing Practitioner

Our Regional Climate Context

https://en.wikipedia.org/wiki/Rain_shadow

CRD Regional Climate Modeling

Highlights from the findings include: -  Extreme temperatures (32°C to 35°C) are projected to occur almost

four times as often in future CRD.-  The amount of precipitation falling during very wet days is projected to

increase by 20%; with precipitation during extremely wet days projecting to increase by 25% in CRD

-  More extreme precipitation events (with 3-hour duration) are projected to occur on average three and a half times as often in future in CRD.

-  There will be fewer Heating Degree Days and a substantial increase in Cooling Degree Days in CRD

The ‘Mediterranean Water Management’ Blues

http://victoria.weatherstats.ca/

www.crkeyline.ca

Keyline History

Yeomans, P.A.. Water for Every farm.

Keyline Scale of Permanence

Watershed Basics

Source: http://www.tankonyvtar.hu/hu/tartalom/tamop425/0032_vizgazdalkodas/ch01s02.html

Water, Silt & Nutrient

Source: Tayler Krawczyk

Natural concentration of soil moisture.

Natural Concentration of Soil Moisture. Photo Source: Campbell Wilson. PRI Australia Article.

On ‘Pooling’ & Drainage

“It is important this result (pooling in the valleys) is treated not a problem of excess moisture to be drained away but as a symptom of water probably being squandered from the upper slopes.”

- Ken Yeoman, Keyline Designs

Source: Tayler Krawczyk

Classic Keyline Landscape Definitions

Photo Source: HUMA. Understanding the Application of Keyline Design.

Valley Line

Valley Line

Ridge Line

Ridge Line

Completing a Keyline Layout on Paper

By Georgi Pavlov. Available for download with donation at huma.org

By Georgi Pavlov

Understanding Classic Keyline Geometry

Source: Doherty, Darren. Regrarians Handbook. 2014


Simplified Contours


Focus on Function! Keep it Simple!


Anomalies

“it is often necessary for compromises with the geometry to have to be made, and that’s okay. It is much better to have a layout that is not entirely correct but that is easy and inspiring to work with, than a layout that is technically correct but that everyone hates working with.” - Georgi Pavlov

What if there are no classic ‘keyline landforms’? Choosing a guideline using common-sense.

How is ‘keyline pattern layout’ different than other layout patterns? What are the advantages & dis-advantages?

Surveying in Practice

!  Start with Contour Maps

!  Flags / Stakes

!  Elevation Survey Tools - Transit Level - Laser Level - A Frame - Water Level (Bunyip)

What if we do not have contour maps available for our region?

!  Demand them from local governments!

!  Affordable drone mapping has come!

Once you have your guideline chosen and layout completed, what techniques are available?

Keyline Cultivation for Pasture Rejuvenation

How is a Yeomans Plow Different any old subsoiler?

About Our Field

Monitoring Program

Sara Duncan, p.Ag

Results: CONTEXT

PILOT PROJECT to discover: � HOW and WHY Keyline Design can be used

on small farms in our region � Whether the intended BENEFITS are

MEASURABLE �  Are INITIAL RESULTS promising?

Opportunity and METHODS for SCALING UP in PRACTICE and ASSESSMENT

Results: HYPOTHESES

Results: HYPOTHESIS TESTS

Ravenhill ●  Clay pan at 20 cm ●  10-15% gravel ●  Silt loam (till) ●  Thin Ah ●  weak lower soil development ●  Gleying in lower slope positions

Bullock Lake ●  25% stones+ fine gravels ●  Silt loam ●  No Ah ●  Shallow depth to auger

refusal on slope ●  Gleying in plots on crest of

hill

Beetnik ●  Sandy loam ●  30% cobble -gravel ●  Thin Ah ●  Well drained in treated area

Results: PENETROMETER MEASUREMENT

Modified fom public domain: https://commons.wikimedia.org/wiki/File:Penetrometer.jpg

Depth of plough

Results: ROOTING

Average (Range) Rooting Depth (cm)

Site Year Control Treatment

Ravenhill 2015 17 (9-23) 18 (14-27)

2016 15 (12-17) 15 (11-17)

Bullock Lake

2015 14 (12-16) 17 (13-20)

2016 18 (17-20) 20 (17-25)

Beetnik 2015 - -

2016 11(9-12) 30 (26-38)

Results: SOIL CARBON

Short-term (<5-10 years) small absolute change in total carbon Active fraction change may be measured more quickly

Total Carbon Active Carbon

Results: SOIL MOISTURE

Results: INFILTRATION

●  Slightly higher rainfall wetting curve

●  Holds moisture longer

●  May reduce moisture retention in some situations (⬆evaporation ? Drainage? Under saturated conditions)

●  May ⬇infiltration to subsoil by holding moisture in topsoil in other situations?

NEXT STEPS

!  Spring/summer and Fall 2017 !  Penetrometer measurements !  Rooting measurements

!  Fall 2017 !  Final soil carbon sample collection !  Final volumetric water content downloads

!  Final report December 2017

OS Design by: Luke Hallam , from Darren J. Doherty

NEXT STEPS

‘Keyline Super Plow’ ?

‘Keyline SuperPlow’

Source: Darren J. Doherty – Carversville Farm Foundation

Other Applications of Keyline Patterning: Market Garden Retrofit

Where & How Has This Been Applied?

Source: Shepard, Mark. Restoration Agriculture.


Versaland, Iowa. Grant Shultz.


Source: Rancho San Ricardo. Pablo Ruiz Lavalle.


Source: Darren J. Doherty


Source: Ridgedale Permaculture – Richard Perkins

Ridgedale Permaculture Model, courtsey of Richard Perkins. By Georgi Pavlov.

Source: HUMA – Georgi Pavlov

Other Water Management Strategies

Swales on Contour

Advantages!

-  Slows overland flow of water & nutrients

-  disturbance creates niche for new plant establishment

-  soil loosening-  soil warming-  planting mound gets above water table-  more soil-air interface

Potential Challenges-  existing infrastructure/ fences-  possible winter springs in unwanted areas-  compaction of temporarily saturated soils if

used-  blocking cold air drainage-  Can create access challenges for machinery

and animals-  Large energy output; permanent feature-  Does not address soil health in between

swales that is causing excess overland flow

Swales -  Contour (retention) vs. Off Contour (diversion) -  Be diligent, plan carefully. Consider advantages and

disadvantages of all options.

Source: Water Harvesting The Permaculture Way. Geoff Lawton.

Source: Hatchet & Seed.

Mimic Forest Ecosystems!

Source: Jacke. Edible Forest Gardens.

Source: Hatchet & Seed

‘Mob’ / Holistic Planned / Management Intensive Grazing

Silvo-Pasture as Drought-Proofing


Silvo-Pasture as Drought-Proofing

Source: Shepard, Mark. Restoration Agriculture.

‘Mob’ / Planned / Management Intensive Grazing

Source: Sheldon Firth. Author of "Letter to a Vegetarian Nation"

Bottomlands: Tile Drainage?

Source: Partners. Conservation Technbology Information Center

Balancing Tile Drainage & Retention

Alternative Drainage for Bottomlands

Still trying to keep slopes between 1:100 – 1:200 to slow erosion.

Source: Nature Conservancy

SOURCE: https://engineering.purdue.edu/watersheds/conservationdrainage/design.html#

Nature’s Pattern for Aerobic Soil in Wet Environments - ‘Pits & Mounds’

Creates microclimates & micro-topography! Areas of permanent aeration!

Hugelkultur

Soil Health

Living Soil as Microscopic Water Storage

Source: Stamets. Mycellium Running.

Soil, Organic Carbon & Water

IRRIGATION POND DESIGN


Is soil removal needed? – Best to re-use on site !  Check your municipal bylaws

Sizing Your Pond – How much do you need?

Use Manufacturer’s Catalogues to determine your expected need!

GPM / GPH / LPM / LPH per emitter X number of emitter. How many zones can the system be divided into? What is max GPM that will be needed at one time?

Sizing your Pond: Assessing Water Needs

Source: Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia

Planning for Evaporation Loss

Planning for Evaporation Loss

L = .67 x 625mm x 1450 m2 L = 607,188 L 607,188 L of evaporation / 4,000,000 total L = 15% Evaporation Loss Evaporation rate can be up to 100% if pond is too shallow.

Example: approx. 4 ML pond

Equation Source: Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia

Source: Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia

Siting Your Pond

Choosing an Experienced Excavation Contractor

-  Ensure they have experience building ponds and understand: 1. regulatory regime 2. importance of separating earth materials for later use 3. importance of diligent soil assessment, design & construction 4. risks associated with embankment ponds

Soil Investigation

Soil Investigation – Texture Sampling

Calculating Catchment

Source: Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia. P. 5

Calculating Catchment

Surveying

Irrigation Pond Design Considerations

https://www.extension.org/mediawiki/files/9/94/Ponds,_Planning,_Design,_Construction.pdf

!  Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia

Excavated Pond

!  Lewis, B. (Barry), 1942– . Farm dams: planning, construction and maintenance. Collingwood, Australia

Wall construction depending on clay content / materials available..

Source:

What If Insufficient Clay is Found?

Source: Darren Doherty. Regrarians Facebook Page. Installing Bentoliner.


LLDPE Liner for Eco-sense pond, Highlands, BC. Photo by Ann Baird.

Products on the Market

! Geotextiles: cushioning, liners, Burp vavles

! Bentonite Clay

!  Gleying

!  WaterSave PL Plug & Seep (biologically friendly?)

! Soil Floc? (biologically friendly?)


Sinuous Channel, Silt Traps & Level Sill Spillways

Spillways

Level-Sill Spillways are preferable to culverted spillways for large ponds. For smaller ponds, culverted spillways like this can work as long as rock rip-rap is added.

This spillway is less than ideal. Level-sill is recommended. Also, there is an alder tree growing on the pond wall which could puncture the retaining wall. No deep rooted trees should be aloud to grow on a retaining wall. Short rooted plants like grasses and blackberries are suitable.

Spillway ‘Guideline’ !  Square root of catchment in hectares = width (in meters)

!  10 acre catchment = 4 hectares = 2 meter wide spillway

LUNCH !

farm water managementcrkeyline.ca/.../2016/12/farm-water-management-.pdf · on small farms in our...

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