Understanding Nutrient & Sediment Loss at Breneman Farms ‐ 4 Understanding Surface Understanding Surface Water Runoff at Breneman Farms Kevan Klingberg, Dennis Frame and Fred Madison UW Extension/Discovery Farms Anita Thompson Amanda Crowe and Tim Radatz Anita Thompson, Amanda Crowe and Tim Radatz UW Madison Biological Systems Engineering
Breneman Farms • On ‐ farm research was conducted on the Breneman f h d d h farm to investigate environmental challenges and opportunities for grass ‐ based dairies on the opportunities for grass based dairies on the Wisconsin landscape, 2002 ‐ 2007. • Surface water quality monitoring was conducted to measure sediment and nutrient loads in runoff water from paddocks that were used for regular water from paddocks that were used for regular rotational grazing, then again used to seasonally out ‐ winter the dairy herd.
Breneman Farms Grazing ‐ based dairy. 42 paddocks. 80 crossbred dairy cows + young stock cows + young stock. (1.6 acres / AU) Coarse textured soil Out ‐ winter cows and older heifers Columbia County, WI
Breneman Farms • Total watershed = • Total watershed = 142.7 acres • Area east of road as well as western wooded area were wooded area were determined to contribute negligible runoff towards watershed outlet. watershed outlet. • Monitored acreage Monitored area: small watershed where cattle are grazed through the season as well as out ‐ wintered. d h h h ll i d adjusted to 28.5 (middle area) acres.
Data • The data presented in this presentation were provided by the UW – Madison Biological Systems Engineering Department, as part of a cooperative project with the UW ‐ Discovery Farms Program.
Data • Breneman Farms, Rio, WI: Monitored surface water runoff from October 2005 – September 2007 2007. • Field year = 12 ‐ months (Oct 1 – Sept 30) – Always represents the year in which it ends • Field year coincides with the crop year.
2006 Field Year • The first year October 2005 – September 2006 = overall average year. g y • Precipitation (ice sleet and snow) was 33 0 Precipitation (ice, sleet and snow) was 33.0 inches, compared to the 30 ‐ year average of 34.5 inches for Portage Wisconsin inches for Portage, Wisconsin.
2006 Precipitation vs. Average 9.0 8.0 30 ‐ Year Average 2006 Precipitation 7.0 tion, in 6.0 Precipita 5.0 4.0 3.0 2.0 1.0 0.0 October November December January February March April May June July August September Season Average 2006 Deviation Deviation Precipitation Precipitation (in) (% of Avg) Fall Sept ‐ Nov 8.39 7.64 ‐ 0.75 91 Winter Dec ‐ Feb 3.89 2.14 ‐ 1.75 55 Spring Mar ‐ May Spring Mar Ma 9.30 9 30 12 10 12.10 +2 8 +2.8 130 130 Summer Jun ‐ Aug 12.95 11.10 ‐ 1.85 86
2006 Field Year • 3 of 4 seasons were drier than normal. • Winter was most severe, with precipitation down by one half. • Still, the big picture showed this to be an average year for total precipitation. y p p
2006 Field Year • Winter began with a snowfall accumulation of 8 Winter began with a snowfall accumulation of 8 inches through mid ‐ December, followed by a warming trend with highs of 35 ‐ 40°F and lows of 28 ‐ g g 32°F. With only shallow frost in the soil at this time, the snowpack melted and infiltrated with no runoff. • Because of the dry winter months, no surface water Because of the dry winter months, no surface water runoff was measured from November through February for field year 2006. y y
2006 Field Year • March began with a 5 to 7 inch snowpack and g p surface water first began flowing through the monitoring equipment on March 4 as temperatures warmed warmed. • Snowmelt generated subsequent surface water Snowmelt generated subsequent surface water runoff events on March 7 and 9. • The runoff events of March 9 and 12 were a result of melting snow and rain on frozen ground.
2006 Field Year • Through the remainder of field year 2006 there Through the remainder of field year 2006 there were two more surface water runoff events occurring on July 20 and August 24 as a result of occurring on July 20 and August 24 as a result of short, intense rainfalls of greater than 1.5 inches each each.
2006 Field Year Runoff Events Precipitation Precipitation Event Runoff Event Runoff Cumulative Cumulative Start Date Type Amount (in) Depth (in) Depth (in) 3/4/06 Snowmelt NA <0.01 <0.01 3/7/06 Snowmelt NA <0.01 <0.01 3/9/06 Snowmelt/Rain NA <0.01 <0.01 3/12/06 3/12/06 Rain Rain 1 5 1.5 <0 01 <0.01 0 01 0.01 7/20/06 Rain 2.0 <0.01 0.01 8/24/06 Rain 1.5 <0.01 0.01 2006 had very little runoff. Less than 1% (0.01 inches) of total precipitation (33 inches) left the site as surface water runoff. 79 % of runoff was during frozen ground conditions. Very little runoff resulted from 3.5 inches of intense summer storms.
2007 Field Year • Second year monitoring on the Breneman farm was another average year for precipitation. • Precipitation (ice, sleet and snow) was 32.4 inches, compared to the 30 ‐ year average of 34.5 inches for Portage, Wisconsin. • Although the annual precipitation was average, 9 months were below average and 3 months were above average precipitation. • Winter 2007 was dry again, concluding with slightly more than Winter 2007 was dry again, concluding with slightly more than one half the normal precipitation. • August 2007 precipitation was 4 6 inches above normal August 2007 precipitation was 4.6 inches above normal.
2007 Precipitation vs. Average 9 0 9.0 8.0 30 ‐ Year Average 2007 Precipitation 7.0 on, in Precipitatio 6.0 6 0 5.0 4.0 3.0 2.0 1.0 0.0 Season S A Average Precipitation P i it ti 2007 2007 Deviation D i ti D Deviation i ti Precipitation (in) (% of Avg) Fall Sept ‐ Nov 8.39 8.80 +0.41 104 Winter Winter Dec ‐ Feb Dec ‐ Feb 3 89 3.89 2 15 2.15 ‐ 1.74 ‐ 1 74 55 55 Spring Mar ‐ May 9.30 8.14 ‐ 1.16 88 Summer Jun ‐ Aug 12.95 14.20 +1.25 110
2007 Field Year • Winter began moderately cool and dry with no surface water runoff measured from November through mid ‐ February for field year 2007 year 2007. • On February 21 st , surface water began flowing through the monitoring equipment as warming temperatures melted most of the five to seven inch snowpack, generating a two ‐ day runoff event. • This event produced twice as much runoff as the entire 2006 winter season (0.01 inches compared to 0.02 inches), but it is not ( p ) large when compared with winter runoff events measured at other Discovery Farms Program study sites.
2007 Field Year • Late February temperatures stayed at or below freezing and 10 to 15 inches of snowpack accumulated by the first week in M March. h • A fast warm up began with temperatures climbing from 26°F • A fast warm up began with temperatures climbing from 26 F to near 50°F over six days. • This created a significant runoff event, March 10 through March 13, which completely melted the snowpack. • This rapid snowmelt, in combination with the frozen soil, produced a very large runoff event (2 85 inches of runoff) produced a very large runoff event (2.85 inches of runoff).
2007 Field Year Snowmelt runoff, March 12, 2007
2007 Field Year • Temperatures remained in the range of 40 to 60°F Temperatures remained in the range of 40 to 60 F through early April. An early April snowfall of five inches melted immediately because of the warm inches melted immediately because of the warm temperatures, yet no surface water runoff was generated as snowmelt water infiltrated into non ‐ generated as snowmelt water infiltrated into non frozen soil.
2007 Field Year • Three more surface water runoff events occurred ee o e su ace ate u o e e ts occu ed through the remainder of field year 2007: – June 10, – June 21, and – July 3. All of these short, intense rainfall events delivered extremely All f th h t i t i f ll t d li d t l low runoff volume, even though the storms each delivered approximately one inch of rain in 20 minutes approximately one inch of rain in 20 minutes.
2007 Field Year Runoff Events Precipitation Event Runoff Cumulative Start Date Start Date Type Type Amount (in) Amount (in) Depth (in) Depth (in) Depth (in) Depth (in) 2/21/07 Snowmelt NA 0.016 0.02 2/22/07 2/22/07 Snowmelt Snowmelt NA NA <0.01 <0 01 0.02 0 02 3/10/07 Snowmelt NA 2.85 2.88 6/10/07 6/10/07 Rain Rain 0.8 0.8 <0.01 0.01 2.88 2.88 6/21/07 Rain 0.8 <0.01 2.88 7/03/07 Rain 1.2 <0.01 2.88 For the 2007 season, 9 percent of the total precipitation left the site as surface runoff (2.9 inches of 32.4 inches). 91 percent infiltration. The majority of 2007 runoff at the Breneman farm was the result of rapid snowmelt on frozen soil, March 10 ‐ 13, which contributed 99 percent of the total annual runoff.
2006 ‐ 2007 Water Budget 2006 2007 Water Budget 12 total runoff Occurrence of Runoff Events events. for Water Years 2006 ‐ 2007 5 snowmelt 1 rain on snow 6 non ‐ frozen 5 Snow Rain on Snow 6 Rain 1 99.68 percent of total surface water runoff volume for the 2 year monitoring period was year monitoring period was during frozen / snow ‐ covered ground conditions.
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