The District’s water system, is a shared system with Harris County Municipal Utility District No. 364 (MUD 364) and consists of three water wells, storage tanks, pumps, pressurization tanks, and miles of pipe to deliver the water to your homes. This system provides water to the residents of Coles Crossing (MUD’s 364,365), The Park at Arbordale (MUD 365), and Stillwater Village (MUD 364), as well as a few surround commercial properties.

The Sanitary Sewer system is a shared system with Harris County Municipal Utility Districts 365 (MUD 365) & 364 (MUD 364) and consists of lift stations, wastewater treatment plant, and miles of pipe to take wastewater from your home to the wastewater treatment plant. The Sanitary Sewer system only collects waste water from home and businesses, it does not collect rainfall runoff. Rainfall runoff is handled by the storm water system which drains to our retention pond and this Cypress Creek.

All the facilities have been equipped, or are in the process of being equipped, with backup power generators to ensure continuous water and sanitary sewer service to our customers.

Water & Sewage Operators: Si Environmental, LLC

6420 Reading Road, Rosenberg, Texas 77471
Phone: (832) 490-1500; Fax: (832) 490-1501
Customer Service:

Do you have an Emergency?
832-490-1601 – Local Dialing
1-877-382-7416 – Toll Free

Water Rates

The District’s water and sewer service rates escalate with higher usage in order to encourage water conservation and responsible use by the District’s residents. For a single family home, the District’s water and sewer rates are as follows:


0 – 10,000 gallons
$5.00 minimum bill

10,001 – 15,000 gallons
$1.00 per 1,000 gallons

15,001 – 25,000 gallons
$1.75 per 1,000 gallons

25,001 – 35,000 gallons
$2.50 per 1,000 gallons

35,001 to 60,000 gallons
$3.50 per 1,000 gallons

Above 60,000 gallons
$5.00 per 1,000 gallons


Flat Rate $14.00 per month

North Harris County Regional Water Authority Fee

10/1/23: $3.60 per 1,000 gallons

The District’s operator reads all the meters within the District on a monthly basis and handles the District’s billing and customer service matters. If you have any questions regarding your water and/or sewer service, please contact SI Environmental at (832) 490-1600 or All customer calls to SI Environmental are reported to the Board of Directors at its monthly meeting.  If you have an emergency repair to report, call the 24 hour hotline at (832) 490-1601.

Water Reports and Plans

Water and Sewer FAQs

What is the “RWA FEE” line item on my bill?

“RWA” is one of the acronyms used to refer to the North Harris County Regional Water Authority. The North Harris County Regional Water Authority is also often abbreviated with the acronym “NHCRWA” (the acronym you will find in the Water Authority’s own materials). When you see these different acronyms, they are both used to refer to the same water authority. The “RWA FEE” you see on your bill is a pass-through fee charged by the NHCRWA to a MUD based on the amount of groundwater pumped and/or the amount of surface water received from the NHCRWA. The fee charged to the MUDs within the boundaries of the NHCRWA is not optional. NHCRWA typically reviews its rate structure and pricing annually and publishes new rates, which can be found in various publications on the NHCRWA website, including in this Updated Pricing Policy linked here.

What is the North Harris County Regional Water Authority (NHCRWA)?

The North Harris County Regional Water Authority, sometimes referred to simply as the NHCRWA or the RWA, is the entity responsible for securing a long-term, reliable supply of wholesale drinking water in our area, designated as North Harris County. As part of this ongoing process, the NHCRWA is in the process of building additional infrastructure to bring surface water, mostly from Lake Houston, to many Municipal Utility Districts, or MUDs, in our area with the goal of converting from the use of ground water (wells) to surface water (lakes, reservoirs) in certain designated areas. More details on the North Harris County Regional Water Authority and its capital improvement projects and plans for conversion can be found on the NHCRWA website at

Notice of Confidentiality and Right to Request Disclosure

Pursuant to Section 182.051, Texas Utilities Code, a customer’s personal, utility usage, and billing information is confidential and may not be disclosed by the District to third parties unless a written request for disclosure is submitted by the customer. If you wish to request disclosure of this information, click here to download and complete the form for submittal to the District.


Next In-District Meeting

December 11, 2023 at 6:00 PM

Special Meeting Agenda (PDF)

Next Business Meeting

December 21, 2023 at 12:00 PM


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