Senator George J. Mitchell Center for Sustainability Solutions

Session B – Flood Assessment and Recovery

Afternoon Session
Presenters are indicated in bold font.

Session Co-chairs:
Rachel Schattman, School of Food and Agriculture, UMaine, rachel.schattman@maine.edu
Sarah Murphy, New England Water Science Center, U.S. Geological Survey, smurphy@usgs.gov (USGS)
Joe Ayotte, New England Water Science Center, U.S. Geological Survey, jayotte@usgs.gov (USGS)

Changes in the hydrologic system due to climate change are increasingly affecting the way humans interact with the environment and, specifically, how the agricultural community will ensure that crops will receive the water they need to be viable. In the rural environment, there also exists a concomitant link between agricultural water needs and the needs for domestic water supply. In this session, we invite talks that address any aspect of assessing, obtaining, and using water resources in agriculture in Maine. Our aim is to present new ideas and research on a broad range of topics in farm and domestic water availability and security. Topics of interest include but are not limited to sources of water for irrigation and farm/domestic supply, changes in water availability in the wake of a changing climate and how that might vary spatially and temporally, method development for irrigation to deliver water to crops more efficiently in time and volume, barriers to water availability and security related to well construction and (or) geohydrologic features.  

Session Schedule

Afternoon Session

• 1:30PM-1:50PM – Welcome and Overview | Presenters: Rachel Schattman, Joe Ayotte
• 1:50PM-2:10PM – Using a soil water balance model to estimate irrigation water demand for major crop types in Maine  | Presenter: Ryan Gordon
• 2:10PM-2:30PM – Diversifying Water Sources at Hart Farm | Presenter: Andrew Toothacker
• 2:30PM-3:00PM – Afternoon Break
• 3:00PM-3:20PM – Quantifying the Hydrologic Impacts of Changing Climatic Conditions on Agricultural Water Resources in New England using the Precipitation Runoff Modeling System | Presenter: Sarah Y. Murphy
• 3:20PM-3:40PM – EnviroWell and Sustainable Safe Water Access | Presenter: Stephen Anderson
• 3:40PM-4:00PM – Collaborative Solutions for Rural Water Security: Perspectives from Moscow, ME | Presenters: Matt Duff, Laurie Stevens

1:30PM – 1:50PM
Welcome and Overview 

Rachel Schattman, School of Food & Agriculture, UMaine, rachel.schattman@maine.edu
Joe Ayotte, New England Water Science Center, USGS, jayotte@usgs.gov (USGS)

1:50PM – 2:10PM
Using a soil water balance model to estimate irrigation water demand for major crop types in Maine 

Ryan Gordon, Maine Geological Survey, Maine Department of Agriculture, Conservation and Forestry, ryan.gordon@maine.gov

Crop water demand models are distributed, process-based models of soil water and its use by crops, which employ climatic data about precipitation and evapotranspiration as well as physical parameters related to soil properties and crop-specific water use. A crop water demand model was developed for major crop types in Maine using the USGS Soil Water Balance (SWB) model code with the FAO-56 evapotranspiration method to estimate irrigation water demand during three years in the 2010s.

The SWB model uses gridded inputs from NRCS soils data, the USDA Cropland Data Layer, and DAYMET daily meteorological data. The model was run at a daily timestep for the years 2012-2013 and 2015-2017. Direct output from the model consists of gridded irrigation water demand in inches, which is the crop water demand that is unmet by precipitation. The model was calibrated by comparing estimated irrigation demand for major crop types to actual reported irrigation depths from a water use survey of farmers for 2016, and values published by the USDA Farm and Ranch Irrigation Survey for 2013. Calibration was achieved by adjusting parameters for crop evapotranspiration, plant stress, rooting zone depths, and irrigation practices.

The calibrated model was used to make estimates of irrigation water demand volume in Maine for the years 2013, 2016, and 2017, by multiplying the modeled irrigation demand by estimates of irrigated acreage for major crops. This calibrated model could be redeployed for later years or repurposed for use with climate projections or hypothetical drought scenarios.

2:10PM – 2:30PM
Diversifying Water Sources at Hart Farm

Andrew Toothacker, Co-owner/Operator of Hart Farm, Hartfarming@gmail.com

A first generation farm business like ours has many infrastructural hurdles to overcome in order to become operational. Developing and improving reliable water sources was a priority when getting our business off the ground and continues to be an area we budget annual improvements for. Since 2020, we have made many investments to improve a drilled well, we have added new pumps and plumbing throughout the property, cleaning out a spring fed pond, and invested in a new experimental water source, the Novel Shallow Well (NSW). Fortunately for our business the risk of installing the NSW paid off and now offers us a reliable, high volume water source in a convenient location.

We credit the diversification of our farm’s water sources as the primary improving factor to our overall resiliency in a climate newly prone to prolonged drought and extreme weather events. Because our water sources responds to drought differently we can maintain consistency with our irrigation needs and stabilize our production-based business. The movement of water through our various soils ultimately informs the ongoing development of our water systems. Significant development and logging above our farm has impacted the 110 acre watershed that flows through our property, making the decisions we make even more critical for the bodies of water beneath our property. These unique factors are leading us to further diversify our hydrologic system with strategically placed retaining ponds to recharge our NSW and reduce erosion by slowing down the overall flow of water in critical areas.

3:00PM – 3:20PM
Quantifying the Hydrologic Impacts of Changing Climatic Conditions on Agricultural Water Resources in New England using the Precipitation Runoff Modeling System 

Sarah Y. Murphy, US Geological Survey, Augusta, ME, smurphy@usgs.gov
Courtney Hammond Wagner, USDA Agriculture Research Service, Burlington, VT
Rachel Schattman, University of Maine School of Food and Agriculture, Orono, ME
Hannah Peplinski, USDA Agriculture Research Service, Burlington, VT

Water availability for irrigation and agricultural use is expected to be affected by changing temperature and precipitation patterns associated with changes in climate. However, the specific hydrologic impacts of localized changes are highly uncertain, with agricultural planning and human activities introducing additional variability. Global Climate Models (GCMs) serve as inputs for the Precipitation Runoff Modeling System (PRMS), a physically-based streamflow model extracted from the National Hydrologic Model, that can estimate hydrological changes under various projected conditions (from GCMs). A New England-scale PRMS model is being calibrated to accurately represent changes in the water cycle that are critical for irrigation, water resources, and other agricultural activities. The U.S. Geological Survey, is collaborating with the U.S. Department of Agriculture (USDA) Agriculture Research Service (ARS), and the University of Maine to communicate the potential impacts of climate change on the water resources farmers rely on so that they will have scientific information to make more informed decisions about future agricultural irrigation practices. This presentation will discuss model selection and show preliminary results from a watershed in central Maine.