What Is Waterfall Project Management Methodology?

Last Updated:Wednesday, June 14, 2023

Don’t go chasing waterfalls, they sing. Yet when it comes to project management methodologies, the waterfall might be just the ride you want your project team to flow down.

But what is waterfall project management methodology, you ask? Thankfully we have a whole explainer article about that below. We’ll start with a definition and move onto specifics like phases and advantages and disadvantages. 


What is waterfall project management methodology? Our definition

Let’s begin with a waterfall project management definition. The waterfall model refers to a project management style and method that stresses the linear and sequential ordering of a project through several stages. 

What’s more, the waterfall approach stresses that everyone's tasks be grouped in stages, and that all tasks per stage must be completed before any tasks in the next stage can begin. This is what is meant by the project management waterfall methodology.

It’s one project management methodology among many, but one that’s particularly adept for large teams thanks to its clear planning stages. On the other hand, it has some relative weaknesses in areas of scheduling and task dependencies. 

When is the waterfall pm methodology appropriate?

Waterfall PM is appropriate when an agile approach is not. What does that mean? Basically, when it comes to waterfall vs agile project management, the key difference is that there is more upfront planning in the waterfall method for the entire project lifecycle than there is for agile teams. 

The waterfall project methodology is also useful for when you have a project that has strong task dependencies and task groups, which mean that one or some part of the project’s workflow cannot be initiated before another or all other project workflows have been completed. By contrast, agile teams can work more independently at their own pace.

When it comes to comparing other PM systems, like the waterfall vs. the critical path method, the waterfall model is more useful and appropriate when there are fewer constraints in terms of timelines and event sequences. You might say that the critical path method is the opposite of the agile methodology, and the waterfall is between them, though probably closer to the critical path. 

Finally, if your team wants to use a WBS, or work breakdown structure, then doing so while you use waterfall techniques is also appropriate, as it would be in agile project management too.

In the end, the waterfall model is appropriate for planned project phases for continued project progress throughout the lifecycle.

How & when was the waterfall approach to project management created?

The history of the project management waterfall model goes back to 1956 and the Symposium on Advanced Programming Methods for Digital Computers. However, the term “waterfall” was not used yet, not until the mid-70s.

The traditional waterfall project management approach perhaps goes back to 1985 when the US Department of Defense developed certain guides and standards that any outside contracting software developers would have to use.

Because of the longevity of the method, it’s key to understanding project management basics, as its tried-and-true, straightforward phase-based model can be compared to other canonical techniques.

For example, waterfall can be contrasted with lean project management conventions, which also date back to the 1950s and the flexible, “just in time” Toyota method. Waterfall is much more linear compared to lean PM, as the latter de-emphasizes hierarchy, and aims for smaller inventories and regular deliverables. 

We could also ask: what is kanban methodology doing differently in relation to the waterfall approach? Kanban, developed just a bit earlier, in the late 1940s in postwar Japan, focused on process improvement, based on lean values and lean thinking. Its emphasis on visualizing the process two-dimensionally and achieving focus is also quite different from the waterfall approach.  


What are the 6 waterfall project management phases

While the exact number ranges, for this article, we will explain the 6 waterfall project management steps or phases. Sometimes you’ll see that there are only 5 given. We’ll shed some light on that discrepancy afterwards.

The 6 waterfall steps are:

1. Requirements

2. Design

3. Implementation

4. Verification

5. Deployment

6. Maintenance

1. First phase of waterfall: Requirements

The first phase of the waterfall methodology is the gathering phase. It is the time to create an upfront project requirements document and decide what metrics to use to measure project success. Here you can also write a project charter and a product backlog of what the end product will do. The idea is to have a clear set of deliverables. You will also make a project lifecycle plan and plan your sprints if you are a software engineering team using some scrum tools. This is also when you do a project schedule, milestones and project budget. All the project stakeholders and team members should be brought in during this phase.

2. Second phase of waterfall: Design

The next waterfall project phase is the design phase. Here you get more into the weeds of your project plan. You figure out which tools or apps the team will be using, whether or not you will use a project template, and what roles everyone will play. Now is the time to set up Kanban boards or Gantt charts. For a software development process, no programming takes place at this stage yet. All the project inputs and outputs are also procured at this phase.

3. Third phase of waterfall: Implementation

The next phase of the waterfall model is the implementation phase, or its the coding phase for a software development team who will use the designs from the previous phase. Here is where the real project work gets done toward your project progress. It’s important during this phase to be mindful of things like task dependencies, so that nobody gets held up from mismanagement. Software development projects will likely have their programmers working in sprints here. 

4. Fourth phase of waterfall: Verification

The next phase of the waterfall process is the verification phase, also known as the testing phase. Few successful projects hit it out of the park on the first go. Verification is where the project team tests the product, compares its performance to what was laid out in the backlog, and perhaps even considers if new features could still be added. For software development, you could test out integrating your code at this stage. 

5. Fifth phase of waterfall: Deployment

The fifth waterfall methodology phase is the deployment phase. This phase is all about producing deliverables. It is likely all stakeholders will be involved during this phase. If you are working on an iterative approach, say, because you’re mixing the waterfall model with an agile methodology, then this deployment phase won’t be about the final product but about an iteration that serves some of the end-use functionality which could be tested.

6. Sixth phase of waterfall: Maintenance

The maintenance phase is the final phase of the waterfall method. By now, the product has been turned over to the customer, stakeholders or client for them to begin using it. As they use it, they may find bugs or problems, or even notice areas where things could be improved. The maintenance phase allows for continuous improvement through minor fixes and changes, but if the changes are large enough, you might go back to the first phase and begin anew.

Now, for those who are curious as to which phase is missing when people say that the waterfall methodology only has 5 phases, it is the deployment and deliveries phase. The logic here is that you could see deployment as the transition from testing to maintenance, or even as the event horizon separating an unfinished deliverable from a finished one.


Ways to use waterfall project methodologies

Waterfall style project management can be used in many ways. Here are what the waterfall method can help you achieve: 

Clear goals

When a client or your stakeholders set out very specifically what they want from the results of a project, then the waterfall methodology in project management is one great way to go about delivering what the customer wants, when they want it, and for the promised price tag.

Organized planning

Whether because of time constraints, cost constraints, or simply how your organization likes to get things done, you can use the waterfall PM approach when it's crucial that there be a clear plan and everyone remain on the same page.

Client satisfaction

There are many different kinds of clients, and some of them are more prone to wanting changes while others never waiver from their initial requests. One of the best ways to apply the waterfall approach is for clients who are sure not to want any changes, otherwise, perhaps agile is more appropriate.


Waterfall project examples

If you’re wondering what an example of waterfall project style might be, here we provide three of them. Below you will find a waterfall project example for the construction industry, for the development of a mobile app, and for preparing to open a neighborhood shop.

Waterfall project example 1: Construction

Because the waterfall is sequential and linear in its progress, it works really well for building a construction project like a house. For example, you couldn’t begin building the walls before the foundation is 100% complete.

You’ll need the client to lay out their requirements before you can begin to do any design and planning. And because you will be working with real materials, various teams from masons to carpenters, equipment rentals, and some time constraints, the fact that the design phase is so thorough before implementation is really useful in construction.  

Waterfall project example 2: Mobile app development

Inventing a new mobile app has many stages from the initial spark of genius for the idea onward. Now, as a software project, there will surely be some agile methods employed here, but where can the waterfall model help out?

Apps can sometimes be very simple in their functions, and applying the waterfall system means the programming team can remain laser-focused on those requirements without letting scope creep get them off track. Also, with the waterfall, you can deploy the app in a beta phase which will help a lot during the maintenance stage.

Waterfall project example 3: Brick and mortar small business

Opening up a small business is a good opportunity to apply the lessons of waterfall project management. In this case, we’ll talk about a real brick and mortar shop, though much can be said about online stores and ecommerce businesses as well.

Say you want to open a donut shop. Your requirements would state what kind of donuts, what neighborhood, how big of a store, and so on. Then, in design, you’ll start really figuring out recipes, costs, location options, management styles, customer experience factors, and any marketing promotion. 

Implementation may begin with signing a lease and doing renovations, hiring and training staff, preparing a grand opening marketing blitz, and so on. Verification can be done once everything is ready but the grand opening date has not yet arrived, allowing for taste tests, practice runs with staff, and other customer experience considerations. 

Finally, deployment is opening, and based on things like sales, reviews and customer feedback, you begin tweaking your business to get it just right for the maintenance phase.


Advantages and disadvantages of waterfall model project management

No one single project management methodology is the best at all times for all purposes, and the waterfall model is no exception. It has its pros and cons. Let’s look at a few of each.

Waterfall project management benefits

Everyone, from the project team to the stakeholders to the clients, get to have a good idea upfront about the project's scope, timeframe and budget.

Since the work doesn’t start right away, you can have enough time to spot problems or risks during the design phase and not let them get too embedded during implementation.

If you have a project with many task dependencies, then applying the waterfall project management methodology will be beneficial to your planning and execution.

The waterfall approach is great for being able to constantly compare your original project plans against specified metrics and milestones to see how well you are doing.

Because of the strict phases, there are sometimes opportunities to restructure the team between phases without losing too much in onboarding new members, since everyone will start new tasks with each new phase.

Finally, another pro of the waterfall method is that it’s great when dealing with customers who might normally demand too many changes throughout the project lifecycle, as the strict structure will discourage them from indulging that tendency.

Waterfall project management drawbacks

The first con of the waterfall PM approach is clearly that aspect that makes it different from an agile approach. This means it’s more difficult to adapt to changes at various points in the project lifecycle.

In comparison to agile methods that have an iterative approach and can therefore begin producing deliverables more quickly, getting results with the waterfall method can be slower.

Whereas agile methods can suffer from project creep, meaning they get to a point where so many changes mean the end is never in sight, the waterfall model has another con: deadline creep. This is when one part of the project gets delayed and then every other part is held up waiting, threatening to go off schedule.

How waterfall project managers benefit from the waterfall management style

Project managers can benefit greatly from applying the waterfall method project management technique.

Waterfall project planning means that managers get to have an excellent bird’s eye view of an entire project’s lifecycle right from the outset. Employing waterfall project planning reduces much of the risks of unexpected obstacles, which can be a good stress reliever on a manager. 

Another advantage to the project manager who is using a waterfall development strategy is that they have some good opportunities between each phase of the project to evaluate their team, offer coaching where needed, shift around workloads, or make other team changes. This regular check up with the project manager helps the team stay motivated and feel connected to the project success. 

Finally, project managers benefit from using the waterfall approach because it can keep the client out of the manager’s hair for most of the process, especially during implementation and verification.


Our conclusion on waterfall methodology project management

When you think of the most effective ways to implement a project management waterfall strategy, you should consider trying out one of the many project management tools on the market. 

A lot of the best CRM and project management software offers features like calendars, Kanbans, timeline views and Gantt charts which are all useful for waterfall project planning, along with other useful PM tools like team communication, time tracking, expense tracking, and invoicing. 

To sum up, the waterfall project management methodology is effective for being simple, straightforward, easy to follow, and slightly impervious to unexpected changes. 

Of course, one cannot avoid all changes, and agile methods are known to be the best at change management. But at least with the waterfall model, you can be confident that there will be few problems that arise from instances when tasks and activities fall out of sequential order. 

As a linear PM system, the waterfall method keeps everyone swimming in the same pool, that is, until it’s time for all spillover down the next fall.