Do you need to test your drinking water for nitrate and nitrite?


  • Dellavalle Laboratory is an ELAP (Environmental Laboratory Accreditation Program) certified laboratory and can analyze your drinking water for nitrate and nitrite to comply with the Irrigated Lands Regulatory Program (ILRP).
  • The purpose of the drinking water monitoring portion of the ILRP is to identify drinking water wells that have nitrate-nitrogen + nitrate-nitrogen concentrations above the drinking water standard of 10 mg/L and to notify the water users.
Meet Martin James
A Dellavalle Consultant
Our Consultants:
  • Over 40+ Years Experience
  • Serving California
  • 4 Offices Statewide

Sampling Frequency:

The sampling frequency depends on the level of nitrate-N + nitrite-N levels in your sample.

If the sum of nitrate-N + nitrite-N is:

  • Below 8 mg/L: Sample for three consecutive years. If results are below 8 mg/L for all three years, then sample once every 5 years.
  • Between 8 mg/L and 10 mg/L: Sample ever year
  • Above 10 mg/L: Notify the water users and no additional sampling is required.

Monitoring Calendar:

  • Beginning January 1, 2019
  • Beginning January 1, 2020

Filling out paperwork:

  • Water Board Drinking water well information:
    • This form allows the laboratory results to be uploaded to the State’s GeoTracker database. It is important to clearly fill out this form or there may be some issues uploading the lab data to GeoTracker.  When naming the well keep it simple and easy to remember.  The well ID can have 10 characters or less. Once results are uploaded to the GeoTracker website, the well name cannot be changed.
  • Assessor’s Parcel Number (APN)
    • You can find your APN by going to your County Assessor’s webpage and searching by address.
  • How to find GPS Location 
  • Dellavalle Work Request:
    • Please fill out all the highlighted areas and the chain of custody (see video above). “Well Name/Field Point Name” and Coalition Member ID must be the same on both forms.

How to Sample:

Bottles and equipment: 

  • 250 mL unpreserved plastic sampling bottle.
  • Ice chest and ice.


  • If the well is not frequently used, run water for 15 minutes prior to sampling.
  • Sample from a tap or spigot as close to the wellhead as possible, and prior to any treatment or filtration – see diagram.
  • Collect the sample into a labeled, unpreserved 250 mL plastic bottle supplied by Dellavalle Laboratory.
  • Label the sampling bottle with an indelible marker. Include the well ID, the samplers name, and the date and time the sample was collected.
  • Keep samples on ice in a cooler. Samples must arrive to the laboratory at a temperature of 4º deg C (39.2º F) or less.
  • Complete out the Water Board Drinking Water Well Member Information form.
  • Complete the Dellavalle Laboratory work order form
  • Request NO3-N and NO2-N analysis.
  • Fill out the chain of custody on the work request form.
  • Submit the samples the same day they are collected.

Sample Delivery:

  • Samples may be dropped off at any of our office locations Monday-Thursday
  • Shipping samples to the laboratory
  • Samples may be shipped overnight to the Fresno Laboratory either by using the shipping method of your choice or via our courier service. Samples must be shipped in an ice chest with ice so that the samples arrives to the lab at a temperature 39.2º F or less.  To schedule a courier pick-up, please contact the Fresno Office at 800-228-986.

What to do if results are above 10 mg/L:

  • If the sum of nitrate-N + nitrite-N is greater than 10 mg/L, the member or owner must notify the water users using  within 10 days. 
  • The member or owner must also send a signed copy of the Drinking Water Notification Template to or mail it to ILRP Program, 11020 Sun Center Drives, #200 Rancho Cordova, CA 95670.