Ag Water Quality

Having clean water is vital to your farm. To ensure that agricultural activities don’t impair water quality, Oregon has an agricultural water quality program, administered by the Oregon Department of Agriculture (ODA).

Examples of water quality problems and reductions needed to meet DEQ water quality standards in Multnomah County
WatershedStream NameIssueChange Needed
Lower Willamette RiverJohnson CreekBacteria78% decrease
Toxics (bound to sediment)94% decrease in sediment deposition in the creek
Temperature40% increase in shade
Sandy RiverBeaver CreekBacteria86% decrease
Temperature15% increase in shade

Oregon’s agricultural water quality management laws require landowners to prevent these kinds of water pollution by using good agricultural management practices. Under the direction of local advisory committees, ODA developed agricultural water quality management plans and administrative rules for our area.  The plans address water quality concerns and provide recommended management practices to prevent and control pollution.

The two management areas in East Multnomah County are the Lower Willamette and Sandy. The plans and rules vary.  As a landowner you should be aware that you are responsible for water quality issues on your property.  Go to ODA’s website to read the plan and rules for your area:

Be pro-active in managing your land, as voluntary compliance with the law is preferable.  A staff person from East Multnomah SWCD can visit your site, help you identify any water quality concerns, and provide technical assistance.  Cost share may be available to help you take action.  We are non-regulatory, which means you can talk to us without worrying about getting in trouble.

The following agricultural water quality issues have been identified in Multnomah County:

  • Soil Erosion: Sediment in surface water degrades fish habitat. Soil can enter surface water through eroding banks and soil-laden runoff.  You must prevent soil from eroding into streams and rivers. You also need to prevent soil from entering ditches that drain to public road ditches or to surface water. See our section on erosion prevention for more.
  • Nutrients: Nutrients found in manure and fertilizer help plants grow, but in excess they can cause algae blooms that remove the oxygen needed by aquatic life to survive. Excess nitrogen can also pollute drinking water in wells. You must prevent manure and fertilizers from leaving your property and entering surface water, either directly or by ditch. See our Nutrient Management section.
  • Temperature: Elevated water temperature is considered a pollutant according to the Oregon Department of Environmental Quality (ODEQ). Water temperatures can increase dramatically when the tree or shrub canopy is removed along waterways, making it harder for threatened and endangered salmon species to survive. See the Streamside vegetation section for more information.
  • Pesticides: Improper application of pesticides can harm people, livestock, fish, and wildlife. Pesticides must be applied as indicated on the label and prevented from entering state waters via drift or erosion.
  • Bacteria: Escherichia coli is a type of bacteria that is found in manure that can harm humans.  You should prevent manure from entering creeks and ditches to protect yourself and your neighbors. Piled animal waste could leave your property via runoff from rain.  Paying attention to where you put your manure pile, covering it, and keeping runoff water away from it are all easy ways to stay in compliance with this rule.

Composted manure can be applied to your fields or shared with your friends and neighbors.  The Manure Connection section of our web site is designed to bring together gardeners searching for sources of local, organic fertilizer with livestock owners and managers with excess fresh and composted manure.