How to use MWELO.com

From Address
to Permit.
Seven Steps.

STEP 01 Free to start
Start With Your Address

Go to My Project and start right away — no account, no payment. Enter your project address and MWELO.com detects your city, ETo and WUCOLS region. If your city isn't on the list, choose the closest listed city.

One payment = one address. You pay once per project address, when you calculate your result. After payment the address, city and ETo are locked to that payment. For a different property, start a new project.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
—Water Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Project Information
Step 1 of 4 · Enter your project details
Project Address
1234 Oak Avenue, Pasadena, CA 91103
City
Pasadena ▾
Reference ETo (in/yr)
52.5
Reference ETo Data for Your City
CityPasadena
CountyLos Angeles
WUCOLS RegionSouth Inland Valley
Annual ETo52.5 in/yr
MWELO Conversion× 0.62
STEP 02 Your Work Is Saved
Come Back Any Time

Your project is saved automatically on this device and this browser. You can close the tab, shut down your computer, and return the next day — your project will be right where you left it.

After you pay, access stays active for 90 days on this device. If you switch to a different browser or device, you'll start with a blank project — email us if you need help recovering your access.

Tip: Finish your project on the same computer and browser you started on. Switching devices means starting over with a blank project on that device.
mwelo.com/Project
My Project →
Project Saved Automatically
Saved in this browser on this device
1234 Oak Ave, PasadenaAddress 🔒
PasadenaCity
52.5ETo (in/yr)
↺ New Project
Project Information
Step 1 of 4 · Enter your project details
1234 Oak Avenue, Pasadena, CA 🔒
Category
Residential ▾
Landscape Area (sq ft)
4,500
STEP 03 Project Info
Enter Project Details

Check the project address and city — your city sets the ETo and WUCOLS region. Choose the Project Category (Residential or Non-Residential) and Project Scope (New Construction or Rehabilitated Landscape), then enter the Total Landscape Area. Use Special Landscape Area only for areas such as pools, edible gardens or recreation turf.

Residential ETAF limit: 0.55  ·  Non-Residential: 0.45
Choosing the wrong category will affect your water budget calculation.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
—Water Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Project Information
Step 1 of 4 · Enter your project details
Project Category
Residential (ETAF ≤ 0.55) ▾
Project Scope
New Construction ▾
Total Landscape Area (sq ft)
4,800
Special Landscape Area (sq ft)
0
Pools, edible gardens, recreation turf
Continue to Hydrozones →
STEP 04 Hydrozones
Define Your Hydrozones

Add one hydrozone for each area of your design that shares the same irrigation method and plants with similar water needs. For each hydrozone enter:

  • Area in square feet
  • Irrigation Method — Drip / Micro-irrigation (IE 0.81), Spray / Rotor (IE 0.75) or Bubbler (IE 0.75)
  • Plants — added in the next step
Tip: The plant with the highest water need in a zone sets that zone's plant factor. Group Low and Very Low plants together — a single Moderate plant raises the whole zone.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
—Water Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Hydrozones
Step 2 of 4 · Define zones and assign plants
Hydrozone 1
Remove Zone
Area (sq ft)
1,800
Irrigation Method
Drip (IE 0.81) ▾
Add Plant Species
Type to search WUCOLS species…
Assigned Plants — highest PF governs zone
white sage · PF 0.2 ✕toyon · PF 0.2 ✕
Hydrozone 2
Remove Zone
Area (sq ft)
3,000
Irrigation Method
Drip (IE 0.81) ▾
Add Plant Species
Type to search WUCOLS species…
Assigned Plants — highest PF governs zone
deer grass · PF 0.5 ✕
+ Add Hydrozone
STEP 05 Plants
Assign Plants to Each Zone

Each hydrozone has an Add Plant Species field, powered by a built-in WUCOLS selector. Start typing a common or botanical name and pick from the suggestions. The selector offers only plants rated for your region, and each one shows its water-use category and plant factor (PF) — so every plant choice is right for your location.

Chosen plants appear as tags in the zone, and the highest PF among them governs it. Plants are listed in the Plant Material Table document, one section per hydrozone, as required by MWELO.

Note: Classifications are region-specific. The same species may be rated differently in San Diego vs. the Central Valley, so only species suited to your region are suggested.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
—Water Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Hydrozones
Step 2 of 4 · Define zones and assign plants
Hydrozone 1
Remove Zone
Area (sq ft)
1,800
Irrigation Method
Drip (IE 0.81) ▾
Add Plant Species
sal
white sage — Salvia apianaLow · PF 0.2
Andean silver leaf sage — Salvia discolorMod · PF 0.5
Aromas salvia — Salvia 'Aromas'Low · PF 0.2
Assigned Plants — highest PF governs zone
toyon · PF 0.2 ✕
STEP 06 Calculate & Unlock
Calculate & Unlock Your Result

When your hydrozones are ready, click "Calculate". The Water Budget tab then asks for a one-time payment of $49 for your project address, paid securely through PayPal. Your result unlocks on the same screen — nothing to copy or save.

Free until now: everything up to this point costs nothing. You pay only to see your result and documents, and the payment covers unlimited edits and recalculations for this address.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
—Water Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Water Budget
Step 3 of 4 · MWELO compliance calculation
Unlock Your Result
& Compliance Documents
$49
One-time payment per project address. Unlocks your result and, once your design passes, all three compliance documents — with unlimited revisions and re-runs for this address.
PayPal
← Adjust Hydrozones
STEP 07 Result & Documents
Review Your Result & Open Documents

You see right away whether your design is within its water budget: ETWU, MAWA, ETAF and a hydrozone-by-hydrozone breakdown. When the design passes, "Continue to Documents" appears and your documents unlock.

Once your design passes, your project includes three documents:

01Water Efficiency Landscape Worksheet
02Plant Material Table by Hydrozone
03Certificate of Completion (PDF, pre-filled with your address)
If you don't pass: your documents stay locked until it does. Click "← Adjust Hydrozones", replace Moderate plants with Low or Very Low ones or reduce the irrigated area, then click Calculate again — as many times as you need, at no extra charge. The table shows which hydrozone uses the most water. Only the project location (address, city and ETo) stays locked to your payment.
mwelo.com/Project
My Project →
1234 Oak Ave…Address
PasadenaCity
52.5ETo (in/yr)
ResidentialType
✓ Within BudgetWater Budget
↺ New Project
1 · Project
2 · Hydrozones
3 · Water Budget
4 · Documents
Water Budget
Step 3 of 4 · MWELO compliance calculation
✓ Design is Compliant with MWELO
ETWU is at or below MAWA. This calculation supports proceeding to documentation.
74,744
ETWU (gal/yr)
85,932
MAWA (gal/yr)
0.55
ETAF (limit)
4,800
Area (sq ft)
HydrozoneAreaIrrigationPFETWU
Hydrozone 11,800Drip0.2014,467
Hydrozone 23,000Drip0.5060,278
← Adjust Hydrozones
Continue to Documents →
Common questions

Quick Answers

Can I edit my project after saving?
Yes — unlimited revisions at any time. Your work is auto-saved on this device every 30 seconds, and you can recalculate as many times as you need before downloading your documents.
Can I get my documents if my design doesn't pass?
Documents unlock only when your design passes the water budget. If it doesn't, go back, adjust your hydrozones or plants and recalculate — as many times as you need, at no extra charge. Only the project location (address, city and ETo) stays locked to your payment.
Can I close the tab and come back later?
Yes. Your project is saved automatically on this device and browser. Close the tab, shut down your computer, come back the next day — everything will be right where you left it. After you pay, access stays active for 90 days on this device.
Can I use my payment for a different address?
No. The address in your project is locked to your payment — one payment, one property. To work on a different address, click "↺ New Project" in the tool and complete a new payment.
What if I switch to a different device or browser?
Your project lives on the specific device and browser you worked on. If you switch, you'll see a blank project and be asked to pay again. We strongly recommend finishing your project on the same device. If you run into issues, contact us at hello@mwelo.com.
Does this work for Santa Monica?
No. Santa Monica has its own local water ordinance that differs significantly from MWELO. This tool is not valid for Santa Monica projects.
I need help with my project. Who can I contact?
Talk to our team — more than 20 years of hands-on MWELO experience preparing and submitting compliance documents. Send us the details of your project through the contact form and we will get back to you. General tips are shared on @mwelo_california.
Talk to the team

20 Years of MWELO.
One Conversation Away.

Behind MWELO.com is a team with more than 20 years of hands-on experience preparing, submitting and getting MWELO compliance documents approved across California. The tool puts that experience at your fingertips — and if your project calls for more, you can talk to the team directly.

Plan checker comments, complex multi-zone projects, local requirements — tell us about your project and we will get back to you.

Talk to the Team → @mwelo_california
Hydrozone Strategy Review

Not sure how to structure your zones for a complex site? We can review your approach before you enter it into the tool.

Plan Checker Correction Notices

Got a correction notice from the city? We help you interpret the comments and revise your document correctly the first time.

Local Jurisdiction Guidance

Some cities have local MWELO amendments. We know which ones and can guide you through the differences before you submit.

Ready to Start?

See Pricing → Go to My Project →