Top 7 Sewage Cleanup & Biohazard Companies in Maryland (2026)

Published: May 30, 20262026497 words2 min read

Key Takeaways

7 sewage & biohazard firms in Maryland qualified for this ranking based on verified data from public sources (BBB, Google, IICRC, EPA, Yelp, Angi, HomeAdvisor).
The top firm in this ranking is Catons Plumbing & Drain Service, with a MetaScore of 100/100.
Every firm here carries at least one publicly verifiable signal — no firm appears in this article without a cited source.
This list is filtered to firms that explicitly offer sewage & biohazard services. Multi-discipline firms appearing here have that service confirmed on their website or in their public certifications.
Methodology is published in full at restorationindex.com/methodology. Firms can request a correction at restorationindex.com/contact.

Sources cited in this article: Better Business Bureau, Institute of Inspection, Cleaning and Restoration Certification, U.S. Environmental Protection Agency, Google, Yelp, Angi, HomeAdvisor, and Restoration Index.

Based on aggregated public-source data from BBB Business Profiles, Google Business Profile reviews, IICRC certified member directory, EPA Lead-Safe registry, Yelp, Angi Super Service Award lists, and HomeAdvisor recognition, here are the top-ranked sewage & biohazard firms in Maryland. Each firm receives a 0-100 Restoration Index MetaScore weighted across 9 sources.

Top 7 Sewage Cleanup & Biohazard Companies in Maryland — Ranked by Multi-Source MetaScore

Catons Plumbing & Drain Service (Baltimore, MD) — MetaScore 100/100. founded 1964. Read the full review.
SERVPRO of Rockville and Silver Spring North (Silver Spring, MD) — MetaScore 85/100. 5.0-star Google rating across 192 reviews. BBB A+ accredited. IICRC certified. founded 2009. Read the full review.
SERVPRO of Frederick County (Frederick, MD) — MetaScore 79/100. 4.8-star Google rating across 354 reviews. BBB A+ accredited. IICRC certified. founded 2012. Read the full review.
SERVPRO of Potomac and SERVPRO of Chevy Chase / Silver Spring (Silver Spring, MD) — MetaScore 77/100. 4.8-star Google rating across 59 reviews. BBB A+. IICRC certified. founded 2012. Read the full review.
Service Pros Cleanup (Silver Spring, MD) — MetaScore 71/100. 4.8-star Google rating across 65 reviews. BBB A+ accredited. founded 2011. Read the full review.
Dry House Restoration (Frederick, MD) — MetaScore 64/100. 4.9-star Google rating across 86 reviews. BBB NR. Read the full review.
Flood Damage Pro of Columbia (Columbia, MD) — MetaScore 62/100. BBB NR. founded 2007. Read the full review.

Top sewage & biohazard firms in Silver Spring

SERVPRO of Rockville and Silver Spring North leads Silver Spring with a MetaScore of 85/100 and 192 Google reviews. Other top-ranked firms in Silver Spring include SERVPRO of Potomac and SERVPRO of Chevy Chase / Silver Spring (MetaScore 77/100), and Service Pros Cleanup (MetaScore 71/100).

Top sewage & biohazard firms in Frederick

SERVPRO of Frederick County leads Frederick with a MetaScore of 79/100 and 354 Google reviews. Other top-ranked firms in Frederick include Dry House Restoration (MetaScore 64/100).

Frequently Asked Questions

How is the Restoration Index MetaScore calculated?

The MetaScore is a weighted average of nine normalized component scores: Google Business Profile reviews (25%), BBB rating + complaint history (20%), IICRC certification (12%), EPA Lead-Safe registry (8%), years in business (10%), Yelp reviews (10%), Angi Super Service Award (5%), HomeAdvisor Top Rated (5%), and regional industry awards (5%). Firms with sparse data have weights redistributed proportionally across the sources we did find. Full methodology at restorationindex.com/methodology.

Who is the top-ranked sewage cleanup & biohazard company in Maryland?

As of May 2026, Catons Plumbing & Drain Service ranks #1 in Maryland for sewage cleanup & biohazard with a MetaScore of 100/100. The full ranking and per-firm breakdowns appear below.

How often is this list updated?

Firm-level data (reviews, BBB ratings, certifications) is refreshed every 30 to 90 days depending on the source. Awards and recognition fields refresh annually. The "Last refreshed" date below the article header reflects the most recent data refresh for this article.

Can firms pay to be included or ranked higher?

No. Restoration Index does not accept paid placement. The MetaScore is calculated identically for every firm in the index, whether or not they have any commercial relationship with Pleiades Consultancy (the publisher of this site). The methodology is published in full so firms can audit how the calculation works.

What if a firm I trust is missing from this list?

Coverage is rolling out city by city. If a firm meets our inclusion criteria (operating in the named region, offering sewage cleanup & biohazard services, with at least one verifiable public signal), they will appear in future refreshes. Firms can also reach out via restorationindex.com/contact to request inclusion.

Sources & Further Reading

Every claim in this article is backed by at least one of the following third-party sources. Linked out to the publisher so you can audit the original.