Stormwater Intrusion Mitigation Services


Client: honeywell aerospace
Partner: stantec

Project TESC plan sheet.

Project TESC plan sheet.

View of area prone to flooding and temporary paver stone access path to equipment.

View of area prone to flooding and temporary paver stone access path to equipment.


Honeywell International operates an aerospace manufacturing facility on a 12-acre industrial campus in Redmond, Washington. As an aerospace manufacturing facility, Honeywell is required by the City of Redmond to maintain an industrial NPDES permit.


Although most of the site is relatively flat, the green space between two buildings on the Honeywell campus has topography sloping toward the western building. During heavy rain events, stormwater was observed to accumulate adjacent to the building footings, which resulted in flooding of below-grade building sections, putting sensitive manufacturing equipment and systems at risk.


Pacific Stormwater assisted with the evaluation of design options and engineering design of temporary and long-term stormwater management solutions which redirect stormwater to mitigate building intrusion while ensuring compliance with Honeywell’s existing NPDES permit. Pacific Stormwater led the coordination with the City of Redmond to ensure that additional clearing and grading and stormwater permits were not required.


• As-Built Records Research
• Data Gap Analysis
• Engineering Alternatives Analysis
• Regulatory Agency Coordination


• Site Grading and Evaluation
• Construction Stormwater Pollution Prevention Plan (CSWPPP)
• Bid-Ready Plans, Specifications, and Cost Estimates
• Plans Generated in AutoCAD