- What the CID Exam Actually Tests
- The 6 Domains at a Glance
- Domain 1: Equipment (40%)
- Domain 2: Hydraulics (16%)
- Domain 3: Scheduling (15%)
- Domain 4: Layout (15%)
- Domain 5: Electrical (7%)
- Domain 6: Maintenance and Operations (7%)
- Exam Format, Fees, and Registration
- How to Sequence Your Study Across Domains
- Frequently Asked Questions
- The CID General Landscape/Turf exam covers exactly 6 domains across 150 multiple-choice questions in 4 hours.
- Equipment is the single largest domain at 40%, making it worth 60 questions on the general exam alone.
- Hydraulics, Scheduling, and Layout together account for 46% of the exam - nearly as important as Equipment.
- Electrical and Maintenance/Operations each represent 7%, but ignoring them can cost you the passing threshold.
What the CID Exam Actually Tests
The Certified Irrigation Designer credential is issued by the Irrigation Association Certification Board, and the exam is administered through IA-approved computer-based testing centers - with paper/pencil options available in select locations. Before you can sit for it, you need to agree to the IA code of ethics and demonstrate irrigation-related experience or education (3 years is the recommended baseline). Once you meet those conditions and pay the fee, you are committing to a rigorous, domain-weighted examination that tests applied irrigation design knowledge - not just textbook recall.
The General Landscape/Turf exam is the foundation. It contains 150 equally weighted multiple-choice questions delivered over 4 hours. After passing the general exam, candidates choose a specialty: Golf Course (50 questions) or Residential/Commercial (100 questions), also within a 4-hour window. Total testing time across both sessions is 8 hours. Every question on the general exam maps to one of six defined content domains, and those domains are weighted - meaning the number of questions you see from each domain is directly proportional to its percentage weight.
Understanding what those domains are, exactly what they test, and how much each one matters is the single most important strategic decision you will make before you open a study resource. For a broader look at what makes this exam demanding, see our article on How Hard Is the CID Exam? Complete Difficulty Guide 2026.
The 6 Domains at a Glance
The Irrigation Association publishes an official content outline for the Landscape/Turf exam. Six domains make up 100% of the general exam content. Here is how they break down:
| Domain | Name | Weight | Approx. Questions (of 150) |
|---|---|---|---|
| 1 | Equipment | 40% | ~60 |
| 2 | Hydraulics | 16% | ~24 |
| 3 | Scheduling | 15% | ~22-23 |
| 4 | Layout | 15% | ~22-23 |
| 5 | Electrical | 7% | ~10-11 |
| 6 | Maintenance and Operations | 7% | ~10-11 |
One pattern stands out immediately: Equipment at 40% is larger than the next three domains combined. But the three middle domains - Hydraulics, Scheduling, and Layout - each sit at 15-16%, meaning a candidate who neglects any one of them is leaving a significant portion of the exam under-prepared. Electrical and Maintenance/Operations are the smallest slices, but at a passing threshold of roughly 70-75%, those 10-11 questions per domain can absolutely be the margin between passing and a retake.
Domain 1: Equipment (40%)
Equipment is the backbone of the CID exam, and its 40% weight is not an accident. Irrigation designers must make equipment decisions on every single project - and the wrong choice has immediate, measurable consequences for coverage, pressure, water use, and system longevity. This domain tests your ability to select, compare, specify, and troubleshoot irrigation components at a professional level.
Domain 1: Equipment - Core Topics
Candidates must demonstrate working knowledge of the full spectrum of irrigation hardware used in landscape and turf applications.
- Sprinkler heads: rotary, fixed, MP rotators, and matched precipitation rates
- Drip and micro-irrigation emitters, driplines, and pressure-compensating devices
- Backflow prevention assemblies: PVB, RPZ, DCVA - applications and code requirements
- Valves: gate, ball, globe, check, and remote control; pressure regulation
- Filters, pressure regulators, and flow sensors
- Controllers and smart irrigation technology (ET-based, soil moisture, weather-based)
- Pipes and fittings: materials, pressure ratings, compatibility
- Pumps: centrifugal, submersible, booster - selection criteria and performance curves
With roughly 60 questions dedicated to this domain, candidates who master equipment selection and application have already answered nearly half the exam before addressing anything else. Our dedicated deep-dive covers every subtopic in detail: CID Domain 1: Equipment (40%) - Complete Study Guide 2026.
Domain 2: Hydraulics (16%)
Hydraulics is the most calculation-intensive domain on the CID exam. The Irrigation Association allows calculators under exam rules - and this domain is precisely why. Candidates must understand how water behaves under pressure, how pipe friction losses accumulate across a system, and how to verify that a design will actually perform as drawn.
Domain 2: Hydraulics - Core Topics
This domain moves beyond component knowledge into applied fluid mechanics for irrigation systems.
- Static and dynamic pressure concepts; pressure loss calculations
- Hazen-Williams formula and friction loss in pipes
- Velocity of flow and pipe sizing decisions
- Water meter and service line sizing
- Pressure zones, booster pump requirements, and elevation effects
- System capacity and flow rate determination from a water source
Hydraulics is where many candidates underestimate the math load. Equation sheets and glossaries may be provided at the testing center, but the ability to set up and interpret calculations efficiently under time pressure is still essential. See CID Domain 2: Hydraulics (16%) - Complete Study Guide 2026 for worked examples.
Domain 3: Scheduling (15%)
Scheduling tests a designer's ability to translate a completed irrigation layout into a practical, water-efficient run schedule. This is not about setting a timer - it is about understanding evapotranspiration, soil infiltration rates, precipitation rates of equipment, and how to build a schedule that delivers the right amount of water at the right time without runoff or under-irrigation.
Domain 3: Scheduling - Core Topics
- Evapotranspiration (ET) and reference ET calculations
- Crop coefficients and plant water demand
- Precipitation rate calculations and matched precipitation
- Soil water-holding capacity and allowable depletion
- Irrigation scheduling methods: water budget, ET-based, sensor-based
- Cycle and soak programming to manage runoff on slopes
- Seasonal adjustment and local climate data application
For a complete breakdown of scheduling concepts tested on the exam, visit CID Domain 3: Scheduling (15%) - Complete Study Guide 2026.
Domain 4: Layout (15%)
Layout tests your ability to design an irrigation system on paper - or, in the specialty exam context, on an actual design plan. For the general exam, questions address design principles, head spacing, zone configuration, and site analysis. This domain bridges equipment knowledge and hydraulic understanding into a coherent, implementable design.
Domain 4: Layout - Core Topics
- Site analysis: soil type, slope, sun/shade exposure, plant material
- Hydrozoning principles and separating irrigation zones by water need
- Sprinkler spacing, head-to-head coverage, and distribution uniformity
- Mainline and lateral routing; valve placement and zone sizing
- Reading and interpreting site plans and as-builts
- Water budget calculations for irrigation design compliance
- Specification writing for materials and installation
The specialty Residential/Commercial exam includes an actual design plan component, so layout mastery is even more critical for candidates in that track. Explore the full scope at CID Domain 4: Layout (15%) - Complete Study Guide 2026.
Domain 5: Electrical (7%)
Electrical represents 7% of the general exam, but the topics it covers are ones where real-world installation errors can cause equipment failure, void warranties, or create safety hazards. The CID exam expects designers to understand basic low-voltage wiring for irrigation controllers, valve wiring configurations, and how to troubleshoot common electrical faults.
Domain 5: Electrical - Core Topics
- Controller wiring: common wire, zone wires, master valve output
- Solenoid valve operation and resistance testing
- Wire sizing, splice techniques, and waterproofing
- Multimeter use for diagnosing shorts, opens, and grounds
- Power supply requirements and transformer ratings
- Low-voltage versus line-voltage distinctions
Even though this domain carries only ~10-11 questions, every point counts at a 70-75% passing threshold. Get the complete treatment at CID Domain 5: Electrical (7%) - Complete Study Guide 2026.
Domain 6: Maintenance and Operations (7%)
Maintenance and Operations rounds out the exam with questions about what happens after a system is designed and installed. Designers who understand long-term system performance write better specifications and make smarter equipment choices at the design stage. This domain tests that forward-thinking perspective.
Domain 6: Maintenance and Operations - Core Topics
- Winterization techniques: compressed air blow-out, gravity drain, automatic drain
- Spring startup procedures and system inspection
- Leak detection and pressure testing of installed systems
- Backflow preventer testing requirements and documentation
- Filter maintenance and screen cleaning schedules
- Troubleshooting low-pressure zones, stuck heads, and controller malfunctions
- Water audit procedures and distribution uniformity field testing
For the full domain-by-domain breakdown, CID Domain 6: Maintenance and Operations (7%) - Complete Study Guide 2026 covers every subtopic in depth.
Exam Format, Fees, and Registration
Cost to Sit for the Exam
The General Landscape/Turf exam costs $250 for IA members and $495 for nonmembers. The specialty exam carries the same fee structure. If you need a retake, the fee drops to $200 (member) or $325 (nonmember) - still a meaningful financial consequence for under-preparation. Annual renewal after certification is $75 (member) or $125 (nonmember), and recertification requires 20 continuing education units every two-year cycle. See the full breakdown at CID Certification Cost 2026: Complete Pricing Breakdown.
Testing Conditions That Matter
Calculators are permitted under IA rules - essential for hydraulics and scheduling math. Smartphones are not allowed in the testing room. Equation sheets and glossaries may be provided at the testing center, but policies can vary; do not rely on reference materials as a substitute for understanding the underlying concepts. The exam is computer-based at IA-approved centers, with paper/pencil options at select locations.
Passing Score
The Irrigation Association does not announce the passing score in advance. It typically falls in the 70-75% range, adjusted by exam form. That means on a 150-question general exam, you are targeting approximately 105-112 correct answers. Because each question is equally weighted and spans all six domains proportionally, weak performance in any domain directly reduces your total score.
How to Sequence Your Study Across Domains
Given the domain weights, a rational study plan allocates time proportionally - but not exclusively. A six-week preparation period for a candidate with solid field experience might look like this:
Equipment Foundation (Domain 1)
- Review all sprinkler, drip, valve, and backflow preventer types
- Study controller and smart technology concepts
- Take domain-specific practice questions to identify gaps
Equipment Depth + Hydraulics Introduction (Domains 1 & 2)
- Continue equipment review: pumps, pipes, fittings, pressure regulation
- Begin hydraulics: pressure loss formulas, Hazen-Williams, pipe sizing
- Practice calculation problems with a calculator under timed conditions
Scheduling and Layout (Domains 3 & 4)
- Master ET, precipitation rate calculations, and scheduling methods
- Study hydrozoning, head spacing, and zone design principles
- Practice interpreting site plans and water budget compliance scenarios
Electrical and Maintenance/Operations (Domains 5 & 6)
- Review controller wiring, solenoid testing, and troubleshooting diagnostics
- Study winterization, startup procedures, and backflow testing requirements
- Do not treat these domains as afterthoughts - drill the specific question types
Full-Length Practice and Weak Domain Reinforcement
- Take full 150-question timed practice tests at CID Exam Prep
- Analyze results by domain - reinforce any domain scoring below target
- Review the CID Study Guide 2026: How to Pass on Your First Attempt for final-week strategy
Key Takeaway
Spend roughly 40% of your total study time on Equipment - mirror the exam's own weighting. But reserve at least one dedicated study session for each of the six domains before you begin full-length practice tests. Discovering a Domain 5 or 6 gap during a practice test is far better than discovering it on exam day.
For targeted practice questions mapped to each domain, Best CID Practice Questions 2026: What to Expect on the Exam explains question formats and how the IA structures scenario-based items. And once you are scheduled, CID Exam Day Tips: 15 Strategies to Maximize Your Score covers pacing, calculator use, and how to approach the hydraulics questions under time pressure.
Curious whether the credential pays off financially? Our Is the CID Certification Worth It? Complete ROI Analysis 2026 examines how the CID affects career trajectory and earning potential in the irrigation industry.
Frequently Asked Questions
The General Landscape/Turf exam contains 150 equally weighted multiple-choice questions delivered in a 4-hour session. All questions map to one of six content domains, with Equipment representing the largest share at 40% (approximately 60 questions).
Equipment is the largest domain at 40% of the general exam. That single domain accounts for roughly 60 of the 150 questions. A candidate who masters Equipment but neglects the other five domains cannot compensate entirely - but strong Equipment performance provides a crucial scoring foundation.
Yes. Calculators are permitted under IA exam rules. This matters most for Domain 2 (Hydraulics) and Domain 3 (Scheduling), where pressure loss calculations, precipitation rate formulas, and ET-based scheduling require numeric computation. Smartphones are not allowed.
The Irrigation Association does not publish the passing score in advance. It typically falls in the 70-75% range depending on the specific exam form. On a 150-question general exam, that means approximately 105-112 correct answers are needed to pass.
The six content domains - Equipment, Hydraulics, Scheduling, Layout, Electrical, and Maintenance and Operations - are defined in the IA content outline for the General Landscape/Turf exam. The specialty exams (Golf Course at 50 questions; Residential/Commercial at 100 questions) include a design plan component and test applied knowledge within a specific project context.
Ready to Start Practicing?
Now that you know exactly what each of the six CID domains covers and how much each one is worth, put that knowledge to work. Our practice tests are mapped to the official IA content outline - so every question you answer builds targeted readiness across all six domains.
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