Yard Drainage in Sherwood, Oregon: Fixing a Soggy Lawn

Why Sherwood Lawns Stay Soggy

Sherwood's rapid growth has filled the hills south of Tualatin with newer subdivisions, and those graded, cut-and-fill lots come with their own drainage quirks. Water flows downhill, and on Sherwood's sloped terrain it often arrives in the lower yards from higher ground, sometimes from neighboring properties. Add western Washington County's heavy clay soil and the steady Pacific Northwest wet season, and many Sherwood homeowners find their lawns turning soggy and their low spots holding water all winter.

A waterlogged lawn is more than an inconvenience. It kills turf, breeds mosquitoes, invites moss, and signals water that may eventually reach your foundation. On graded subdivision lots, the soggy spot is often at the base of a slope where water naturally concentrates. The good news is that yard drainage problems are solvable. The key is matching the right solution to your specific soil, slope, and water source, which begins with understanding what is actually happening on your property.

Common Causes of a Soggy Sherwood Lawn

Hillside and Slope Runoff

Many Sherwood lots sit on or below graded slopes. Water flowing downhill collects in the lower yard, often from areas well beyond your own property line.

Heavy Clay Soil

Western Washington County's clay drains slowly and holds water near the surface. After rain, the upper soil saturates and water sits on top because it cannot percolate down quickly.

Cut-and-Fill Grading

Subdivision lots are often cut and filled during construction, which can leave compacted areas and slopes that direct water toward the house rather than away.

Compacted Soil

Construction traffic on newer lots compacts the ground, reducing what little drainage clay offers and worsening surface ponding.

Downspouts and Runoff

Roof water dumped into the yard concentrates a large volume in one place, and on clay it has nowhere to go.

Yard Drainage Solutions That Work in Sherwood

Because clay drains poorly and slopes concentrate water, the most effective Sherwood solutions move water across or off the surface and intercept hillside flow.

Curtain Drains

On sloped lots, an uphill curtain drain intercepts water flowing down from above before it reaches the lawn. This is one of the most valuable tools on Sherwood's graded subdivision lots.

Surface Grading

Re-establishing a slope away from the house and toward a drainage outlet is often the most cost-effective fix. Sherwood's terrain frequently makes a gravity outlet achievable.

Swales

A swale is a shallow, gently sloped channel that collects and directs surface water to a discharge point. Swales work well for routing collected runoff across a property to a safe outlet.

Area Drains and Catch Basins

For persistent low spots, an area drain with a grate collects pooled water and pipes it away. These handle the depressions and slope-base wet spots common on graded lots.

Downspout Management

Extending downspouts on solid pipe to discharge well away from the lawn removes a major water source before it ever soaks the turf.

Sherwood's Soil and Terrain Challenge

Western Washington County receives substantial annual rainfall, concentrated in the cool months when the ground stays saturated and evaporation is low. The clay soils drain slowly and hold water near the surface, the classic recipe for a soggy lawn. Sherwood's hilly, graded subdivisions add slope runoff to the mix, so water arrives from above and concentrates in low yards.

This is why surface-first and interception strategies, curtain drains, grading, swales, and area drains, tend to outperform deep buried drains on Sherwood lots. The goal is to intercept hillside water and route surface water to a safe outlet rather than waiting for slow clay to absorb it. Our yard drainage cost guide for Oregon explains how these approaches compare and what each typically costs.

What Yard Drainage Costs in Sherwood

Yard drainage projects range widely depending on the solution and the size of the problem. A simple regrade or short swale is a modest project, while a comprehensive system with a curtain drain, multiple area drains, and a long outfall run is a larger investment. Industry baseline ranges for residential yard drainage commonly fall between a few hundred dollars for minor work and several thousand for a full system, with per-linear-foot drain costs often running in the $25 to $60 range.

Sherwood's clay soil and hillside interception work can push projects toward the higher end. Published ranges are a starting reference, not a quote. The accurate number comes from a site assessment.

Why a Site Assessment Comes First

Soggy lawns have many possible causes, and the wrong fix wastes money. An on-site evaluation lets us identify whether your problem is slope runoff, clay, compaction, grading, or downspouts, and then design the most cost-effective solution. We check the slope, trace the water source, including water arriving from neighboring lots, and confirm where water can discharge.

A contractor who walks your Sherwood property will recommend a targeted plan, often including hillside interception, rather than a generic drain that may not address the real issue. That is the difference between a lawn that dries out and one that floods again with the next storm.

Get Your Sherwood Yard Drainage Assessment

A soggy lawn does not fix itself, and on graded subdivision lots it tends to recur each wet season. Cojo Excavation & Asphalt provides free, no-obligation drainage assessments for Sherwood homeowners. We evaluate your soil, slope, and water source, then deliver a clear plan to dry out your yard.

Start with the overview in our guide to property and site drainage in Oregon, then learn more about our excavation services and how we solve yard drainage problems across Washington County.

Request a free assessment — we respond within 24 hours.