In construction, delay categories include Acts of God, owner-controlled, and contractor-controlled—performance-related isn't a standard category.

Outline (brief skeleton)

• Hook: delays happen in sanitary engineering projects, and understanding why helps everyone move forward.

• Quick recap of delay categories: Acts of God, Owner-controlled, Contractor-controlled, and the one that isn’t a standard category.

• Deep dive into each category with practical examples from sanitation projects.

• Why “Performance-related” doesn’t fit the typical delay framework.

• How to think about delays in real projects: documentation, scheduling tools, and risk thinking.

• Quick tips for students exploring this topic in the MSTC curriculum.

• Takeaway: clarity on cause, responsibility, and how teams move past setbacks.

Delays come with the territory in sanitary engineering work. Think about a city’s wastewater upgrade, a stormwater tunnel, or a water treatment plant extension. The gears grind, decisions lag, and suddenly the schedule looks a little longer than planned. The good news is that most delays fit into a handful of familiar categories. Recognizing which bucket a setback falls into isn’t about assigning blame; it’s about understanding responsibility, updating plans, and keeping the project moving with as little disruption as possible.

A quick refresher on the four options you might see in a quiz or a course discussion:

• Acts of God

• Owner-controlled

• Contractor-controlled

• Performance-related

Which one doesn’t belong? If you’re sticking to the standard framework used in project management for construction and engineering, the odd one out is Performance-related. Let me explain why, and then we’ll unpack each category so you can spot them in real-world projects.

What counts as an Acts of God

Acts of God—often labeled as force majeure in contracts—cover events nobody could foresee or prevent. In sanitary engineering, these events aren’t just abstract; they’re sometimes dramatic. Picture extreme flooding that halts excavation, a hurricane that shuts down an on-site asphalt laydown yard, or an earthquake that damages a pipeline trench before it’s backfilled. These delays aren’t caused by any party’s misstep. They’re natural events that push the schedule forward, stress-test contingency plans, and force teams to re-sequence work.

Key takeaways:

• These events are external, unpredictable, and beyond the contractor’s or owner’s control.

• They’re usually addressed in contracts with temporary suspensions, revised milestones, and cost adjustments.

• From a scheduling perspective, you’ll want to include float or contingency buffers to absorb these shocks without cascading delays.

Owner-controlled delays: choices and changes

Owner-controlled delays come from the stakeholder who funds and ultimately approves the design. In sanitary projects, that’s often the city, utility, or a government agency. Think late approvals on critical design details for a new lift station, changes in the project’s scope to incorporate newer regulations, or funding bottlenecks that push procurement pauses.

Two big patterns show up here:

• Decision lags: the owner takes time to review, approve, or redirect design elements.

• Scope changes: after design work begins, the owner asks for modifications—perhaps to meet environmental standards or to connect to a different trunk line.

The practical impact? Schedule slippage that’s not the contractor’s fault. The fix is transparent communication, updated baselines, and a well-documented change-management process. In the MSTC sphere (you know, the broader curriculum covering project controls and risk management), you’ll see this tied to governance, approvals, and how risk is allocated in contracts.

Contractor-controlled delays: when the schedule takes a hit on the field

Contractor-controlled delays are the ones you typically think of when you picture a construction site running behind. They include issues like mismanaged labor, equipment breakdowns, late deliveries of long-lead items (think specialized valves, large pumps, or toxic sludge handling gear), or the scheduling of activities that cause the critical path to stretch.

From a practical angle:

• The contractor’s performance on site—planning, productivity, and resource management—directly shapes this category.

• Weather can be a factor here, but if it’s interwoven with poor site management (like not scheduling enough crews or underestimating critical tasks), it blends into contractor control rather than pure Acts of God.

The lesson here isn’t to assign blame; it’s about improving management practices:

• Tight daily coordination on site tasks

• Reliable procurement processes

• Accurate equipment maintenance plans

• Clear communication channels with the project team

Why “Performance-related” isn’t a standard delay category

This is where a lot of students pause and ask, “But what about performance-related delays?” Here’s the thing: performance is essential, but it’s not its own delay bucket in the standard taxonomy. Performance metrics tell you how effectively work is proceeding—how quickly tasks complete, how quality aligns with spec, how safely work is conducted. If a project lags because performance is off, that lag usually maps back to one of the three main delay buckets above (owner, contractor, or acts of God) or to a combination of those factors.

In short, Performance-related is more of a label for evaluating execution rather than a standalone root cause category. You’ll see it discussed in dashboards, earned value conversations, or post-project reviews, where teams ask, “Did we perform here or there? How did that affect the schedule?” Those questions help diagnose underlying issues that may stem from decisions, resource allocation, or risk responses—but the delay still lands in one of the standard buckets when you map it to responsibility and control.

Connecting the dots: from theory to a real-world lens

Let me explain with a practical lens you’d encounter in sanitary engineering projects. Imagine a project to rehabilitate a municipal wastewater treatment plant. The team has to install new aeration basins, upgrade sludge handling, and reroute several influent lines. You’ll likely see:

• An Acts of God event: a flood season hits, delaying soil clearing and trench work.

• An Owner-controlled scenario: regulatory authorities require additional permits, dragging out the design closeout and approvals.

• A Contractor-controlled episode: a crane breakdown stalls installation of large-diameter pipelines, shifting the critical path.

Now, where does Performance-related fit? Perhaps the project’s early-phase performance metrics show the team is lagging in achieving target production rates in the lab, or there’s a discrepancy between design calculations and as-built performance. Those observations trigger a deeper dive into root causes, which could involve design tinkering (owner-related), procurement choices (contractor-related), or unexpected ground conditions (acts of God). In that analysis, the concern is performance, but the delay itself is still mapped to a standard category of cause and responsibility.

How teams handle delays in these settings

Clear documentation matters. When a delay happens, logging its category helps everyone understand who should adjust the plan, who covers costs, and how to set new milestones. The typical playbook includes:

• A delay log with category, cause, estimated impact, and responsible party.

• A revised schedule that shows the new critical path and updated float for the remaining tasks.

• Change-management records that capture approvals, scope modifications, and cost implications.

• Regular risk reviews that reassess remaining buffers and highlight new threats or opportunities.

In the MSTC world, you’ll also encounter scheduling tools and methods that make this easier:

• Critical Path Method (CPM) to pinpoint which tasks drive the project’s finish date.

• Earned value management (EVM) to compare work completed with budget and schedule expectations.

• Scheduling software like Primavera P6 and MS Project to visualize timelines, dependencies, and resource loading.

• Risk registers and contingency planning so buffers aren’t just a nice idea but a concrete part of the plan.

A few practical takeaways you can apply

• Learn to name the delay, not just describe it. If you say, “the owner delayed procurement approvals,” you’ve placed accountability and opened a path for plan adjustment.

• Keep the documentation tidy. A short note of what happened, when it happened, and who agreed to the new baseline is gold later when conversations turn to claims or cost adjustments.

• Build buffers where it makes sense. In water and wastewater projects, weather windows and long-lead items are common culprits; proactive scheduling can soften their impact.

• Don’t neglect the performance lens. If metrics show a performance gap, investigate whether the root cause sits with design choices, procurement timing, or field execution—and map it back to the right delay bucket.

A quick visit to the real-world flavor

Sanitary engineering projects sit at the intersection of engineering rigor and community impact. You’re not just building pipes and tanks; you’re shaping reliability, public health, and environmental stewardship. That means the schedules you manage aren’t only numbers in a Gantt chart. They represent service continuity for communities, the protection of water quality, and the resilience of infrastructure against nature’s unpredictability. That’s a weighty but incredibly rewarding context to bring into your daily work.

Digressions that still connect

As you study, you’ll cross paths with topics like contract wording, risk shifting, and supplier relations. It’s tempting to treat them as separate boxes, but the truth is they’re part of a single story: how we anticipate, respond to, and recover from delays. If you’ve ever waited on a permit, watched a crane wheel into position, or seen a field crew adjust after a weather dip, you’ve felt the same logic at work—planning plus flexibility yields progress.

A few pointers for navigating the learning path

• Tie every delay to a category. It’s a habit that makes reporting smoother and decisions clearer.

• Practice with real-world scenarios. Look at case studies from municipal projects, wastewater upgrades, or stormwater improvements to see how different teams categorize and recover from delays.

• Pair your technical notes with the human side. Understanding stakeholder coordination, funding rhythms, and regulatory calendars makes you a better problem-solver.

• Use the glossary. Terms like “critical path,” “float,” “lead time,” and “change order” aren’t just jargon—they’re the language that links planning to execution.

Closing thought

Delays aren’t inherently bad; they’re information. They tell you where the plan needs reinforcement, which party holds the course of action, and how to adapt without losing sight of the project’s goals. In the MSTC landscape, you’ll build a toolkit that helps you read these signals clearly, map them to responsible sources, and adjust with confidence. Remember the three standard delay buckets—Acts of God, Owner-controlled, and Contractor-controlled—and keep in mind that Performance-related is more of a performance lens than a standalone root cause. With that frame, you’ll navigate complex sanitary engineering projects with both technical precision and steady, human-centered judgment.