Some of the most common causes of poor drainage or standing waters are the impacts of environmental factors such as beavers and excessive vegetation. If you are observing slow drainage along a known ditch or stream, but you don’t see any signs of beaver activity or excessive vegetation, the issue could be downstream from your site. Attempt to contact neighboring property owners and alert them of your drainage concerns.

Beavers – If beaver dams are restricting flow, contact the
 WA Department of Fish and Wildlife’s Coastal Region Office at 360-249-4628. Dam removal requires a Hydraulic Project Approval. There may be options to reduce impacts of beaver dams using pond levelers and culvert fencing. Visit www.beaversnw.org for more information. Beaver relocation may also be an option in some situations.

Vegetation – Invasive and noxious weeds thrive in and along drainage channels. Problem species such as reed canarygrass (pictured) can outcompete native plants, create dense stands and lead to siltation in streams and ditches. Removing vegetation below the ordinary high-water line (OHWL) in fish-bearing streams requires an HPA from WDFW and must occur in the assigned fish-window for that stream. Drainage ditches and fish-bearing streams have different regulations for removing vegetation, and permits may be required in some instances. Contact Pierce County staff or your local WDFW office for additional information. 

Changes in land use or management can lead to drainage problems. If farm practices have been altered in recent years, soil conditions may have changed. This may include a change from pasture to cropland (or vice versa), introducing a new tillage practice, changing equipment or tractors, or intensifying livestock grazing. There are resources available to farms and landowners to help identify and alleviate these problems, including from WSU-Extension, Pierce Conservation District and local USDA-NRCS staff.

Practices that can negatively affect drainage:

• Repetitive tillage using the same implement
• Not working fields along contours
• Working in fields when soil moisture is high
• Over-inflated tires on tractors and implements
• Not using designated field roads/paths
• Low organic matter content
• Poorly maintained or improperly designed drainage features and infrastructure
• Lack of crop rotations
• Changing feeding locations for livestock

Soil management to reduce compaction:

• Subsoiling in early fall and in spring, if possible
• Vary tillage equipment usage by depth and action
• Inflate tires to lowest possible rating for safe use
• Consider cover crops and/or composting/manure options
• Crop rotations, including fallow cycles
• Get your soil tested in problem areas (physical properties – NOT fertility)
• Work in fields before rain events or irrigation rounds when possible
• Repeated use of areas already compacted by equipment or animals
• Re-seed/over-seed pasture to maintain stand health (reduces overgrazing)
• Avoid over-irrigating fields

Over time, infrastructure like ditches and streams that convey run-off can be altered by the moving water in them. To determine if this is the cause of your drainage issue:

• Inspect ditches for proper shape and gradient to convey runoff
• Inspect culverts for damage

If you see sediment or debris, please complete the Request for Action form, providing as much detail as possible.

The soils present on any given parcel are mapped by the USDA-NRCS (Pierce County Soil Survey). Soil maps should be used to better understand your site and how its soil properties might influence drainage. Soil maps are not 100% accurate and cannot account for every small inclusion of soils that do not behave as the primary mapped soil in an area. Soil qualities change as you go deeper in the profile, and sometimes there are subsoil layers that can reduce infiltration and limit root growth.