EXPERT WITNESS SERVICES
Construction disputes involving drainage and land movement require more than opinions. They require experienced professionals who can investigate site conditions, identify contributing factors, and clearly explain complex technical issues.
Millsap Degnan provides qualified expert witness services focused specifically on drainage failures, slope instability, erosion, retaining wall performance, foundation movement related to site conditions, and other land movement related claims. Our team performs objective investigations, detailed technical analysis, and professional reporting to help determine the causes of site related failures and evaluate potential corrective measures.
Whether you need an initial case evaluation, expert analysis during litigation, or testimony at trial, we provide independent opinions supported by decades of engineering and construction experience.
HOW WE CAN HELP
EXPERT WITNESS SERVICES
Qualified expert testimony for disputes involving drainage, erosion, slope instability, retaining wall failures, and land movement related claims. We provide expert reports, deposition testimony, mediation support, arbitration testimony, and courtroom testimony that clearly explains complex site related issues.
DRAINAGE & LAND MOVEMENT INVESTIGATIONS
Comprehensive site investigations to identify the causes of drainage problems, soil movement, erosion, settlement, and other site related failures. We evaluate existing conditions, contributing factors, and potential corrective solutions.
INSURANCE CLAIM SUPPORT
We assist insurance carriers, adjusters, attorneys, and property owners by providing independent evaluations of property damage associated with drainage failures, slope movement, retaining wall failures, and erosion related claims.
SITE FAILURE ANALYSIS
Detailed evaluation of site related construction failures, including grading deficiencies, improper drainage systems, inadequate surface water management, retaining wall performance, and other factors that contribute to land movement and property damage.
WHO WE WORK WITH
Attorneys
Insurance Companies
Property Owners
Homeowners Associations
Contractors
Developers
Geotechnical Engineers
Civil Engineers
Public Agencies
TYPES OF CASES WE HANDLE
Drainage Failures
Landslides and Slope Movement
Retaining Wall Failures
Erosion and Soil Loss
Foundation Movement Related to Site Conditions
Site Grading Deficiencies
Surface Water Management Failures
Stormwater Related Damage
Property Damage Investigations
Settlement Related to Drainage Issues
Hillside Instability
DOUGLAS K. DEGNAN
Principal Manager with Millsap Degnan & Associates Inc. and over 40 years of proven hands-on construction experience specializing in hillside construction, structural repairs, and complex site conditions. Provides expert consulting services including site inspections, condition assessments, construction evaluations, repair recommendations, line-item cost estimates, and expert opinions. Extensive litigation experience includes depositions and trial testimony involving retaining walls, drainage, landslides, structural repairs, and construction disputes.
Litigation and Expert Witness Experience
Ye v. Richman
Sausalito, California
Year: 2025
Attorney: Alexander Klein
• Construction consultant and expert retained in connection with a construction related dispute involving Ye v. Richman.
• Conducted a site visit and provided expert opinions regarding the condition and rehabilitation of an existing retaining wall.
• Prepared a detailed line-item cost estimate for the proposed retaining wall rehabilitation and associated corrective work.
Brooke Wagner Matter
San Francisco, California
Year: 2025
Case No. CGC 21 596423
Attorney: Steven Flynn
• Construction expert retained in connection with a dispute involving underpinning and structural repairs for a hillside residential project.
• Conducted site inspection and construction evaluation, participated in expert deposition, and provided opinions concerning
construction methods, underpinning, structural repairs, and related construction issues.
• Underlying Litigation: Christina M. Sagonowsky v. Jonathan Wetzel et al, San Francisco County Superior Court.
Schacter Matter
San Francisco, California
Year: 2025
Attorney: Law Offices of Scott C. Stratman
• Construction consultant and expert retained in connection with a construction related dispute involving Blair Williams and David
E. Hunter III.
• Conducted site inspection and construction evaluation and provided consulting services and expert opinions concerning disputed construction issues.
Delfs v. Lu
Redwood City, California
Year: 2024
Attorney: Bertrand, Fox, Elliot, Osman & Wenzel
Engineering Consultant: Miller Pacific Engineering Group
• Construction expert retained in connection with a dispute involving retaining wall construction and related site improvements.
• Conducted site inspection and evaluation of the property and retaining wall conditions and provided opinions concerning the construction and condition of the improvements.
• Worked in coordination with Scott Stephens of Miller Pacific.
Popjevalo et al. v. Wilkinson et al.
Mill Valley, California
Year: 2024
Attorney: Rifkind Law & Mediation, P.C.
• Construction consultant and expert retained in connection with a claim involving retaining wall failure.
• Conducted site inspection and evaluation of the retaining wall and surrounding site conditions and provided opinions concerning the failure and related construction conditions.
Top Solutions LLC v. East Bay Municipal Utility District
Contra Costa County
Year: 2024
Court: Contra Costa County Superior Court
• Construction consultant and expert retained in litigation involving construction related claims associated with a flooded property.
• Conducted site inspection and evaluation and provided opinions concerning property conditions, potential causes of flooding, and related construction issues.
Ashle v. Prenter
Marin County
Year: 2023
Case No.: CIV 1900406
Attorney: Ragghianti Freitas
• Construction expert retained by Ragghianti Freitas on behalf of Robert Prenter in connection with a property dispute involving an alleged landslide between neighboring properties.
• Conducted an evaluation of the nature and extent of property damage and provided expert opinions concerning the cause of the
damage and associated repair costs.
• Provided expert testimony during a 15-day jury trial regarding the nature and amount of damages.
• The jury found in favor of Robert Prenter and awarded $780,000 in damages.
Julie Glavin v. William Hernandez
San Rafael, California
Year: 2023
Case No.: CIV2301336
• Construction expert retained in connection with construction related issues at the subject property.
• Conducted site inspection and construction evaluation, participated in deposition, and provided opinions concerning construction conditions and related project issues.
Miller v. Konik et al.
Novato, California
Year: 2023
Case No.: 2200448
Attorney: Rifkind Law & Mediation, P.C.
• Construction consultant retained in connection with a property drainage dispute.
• Conducted site evaluation and provided consulting services concerning site drainage, drainage improvements, construction methodology, and recommended corrective measures.
• Also performed construction work associated with the drainage improvements.
Professional References
Craig Herzog / Herzog Geotechnical Engineering
Irv Swartz / ILS Associates Inc
Dietrich Stroeh Associates / CSW Stuber Stroeh Engineering
Scott Stephens / Miller Pacific Engineering Group
Jeff Raines / Terraphase Engineering
*Additional references available
FREQUENTLY ASKED QUESTIONS
What types of cases do you serve as expert witnesses for?
We provide expert services for drainage failures, landslides, slope movement, retaining wall failures, erosion, grading deficiencies, stormwater damage, and hillside instability.
Do you provide expert reports?
Yes. We prepare detailed reports documenting site observations, technical findings, applicable construction standards, and professional opinions.
Can you testify in court?
Yes. Our experts are available for depositions, mediation, arbitration, and courtroom testimony.
Do you work with homeowners?
Yes. We work directly with homeowners, attorneys, insurance professionals, contractors, and commercial property owners.
Ready to Discuss Your Case?
Whether you need an independent construction evaluation, technical consultation, or qualified expert testimony, our experienced team is ready to assist. Contact us to discuss your case and determine how our expertise can support your legal or insurance matter.