How do we manage Maui’s water resources?
* Hundreds of irrigation or industrial wells are throughout the island of Maui. Managing the DWS system is only one part of managing Maui’s water resources for the future. supply water within its service areas, the State Commission on Water Resource Management (CWRM) is tasked with permitting and regulating new source development.
Does Maui have a water filtration system?
Filtration systems have been installed on the five county wells and several are in regular operation. Maui has been the center of much innovation in water resource development. The ancient Hawaiian auwai (water transport ditch) system is a marvel of engineering, still functioning today.
How much ground water does Maui pump each day?
(DWS 2003, pumping reports) An average of 75 MGD of ground waters, some brackish, some not, is pumped and used for private irrigation purposes on Maui every day. (2002 CWRM reports).
How did Maui get its water?
Recognizing that Maui had shallower aquifers along most of its coasts, plantation engineers developed the “Maui well” in the 1920’s that skimmed millions of gallons of fresh water floating on the seawater surface of the water table. These provided onsite irrigation to fields in the arid plains.
How do water treatments plants work?
As sewage enters a plant for treatment, it flows through a screen, which removes large floating objects such as rags and sticks that might clog pipes or damage equipment. After sewage has been screened, it passes into a grit chamber, where cinders, sand, and small stones settle to the bottom.
How does Maui get its fresh water?
For Central Maui (Kahului, Wailuku, Waihee, Maalaea, Kihei, and Paia) your water is groundwater from the Iao Aquifer under the West Maui Mountains. That water is naturally filtered by lava rocks, disinfected, and sent to your home. A small amount of filtered surface water is added to the Central System at the Iao WTF.
What does Maui do with its sewage?
Only highly-treated wastewater goes into all of the County of Maui's underground injection wells. The County of Maui processes this water to remove solids and contaminates to dramatically improve the water quality so that it can be reintroduced into our environment with minimal effect.
Does Hawaii have sewage treatment plants?
The 2004 Clean Watersheds Needs Survey found that 61.9% of Hawai'i residents are served by a centralized wastewater treatment facility. Of those, 34.7% received centralized wastewater treatment at the secondary, greater than secondary or no discharge treatment level.
How does the water cycle work in Hawaii?
In the Hawaiian Islands, where we are surrounded by water and have plentiful sunshine, most of the evaporation in our water cycle takes place offshore. Ocean water is warmed by the sun, then water molecules evaporate in the form of vapor, rising into the atmosphere. Aloft, the moisture is blown onshore by trade winds.
Where does Maui get drinking water?
For Central Maui (Kahului, Wailuku, Waihee, Maalaea, Kihei, and Paia) your water is groundwater from the Iao Aquifer under the West Maui Mountains. That water is naturally filtered by lava rocks, disinfected, and sent to your home. A small amount of filtered surface water is added to the Central System at the Iao WTF.
Where does all the poop go in Hawaii?
There are approximately 88,000 cesspools in Hawaii; most of which are small-capacity cesspools. Property owners and operators must comply with all federal and state requirements for cesspools. The HDOH Wastewater Branch oversees and permits all onsite wastewater systems, including cesspools.
Does Hawaii dump sewage into the ocean?
Still the most common method for disposing wastewater in Hawai„i is through the injection well. Wastewater injected into the ground becomes part of the groundwater system, and eventually discharges into the ocean.
How is wastewater treated in Hawaii?
Cesspools in Hawai'i They don't treat wastewater, they merely dispose of it. Cesspools concentrate the wastewater in one location, often deep within the ground and in direct contact with groundwater, causing groundwater contamination.
How much fresh water is diverted to irrigation ditches in Maui?
An average of 272 MGD of fresh stream water from both East and West Maui streams is diverted into irrigation ditches each day. (WDUP, 1990) Only two golf courses on Maui use stream waters for irrigation, Sandalwood in Waikapu and the Kapalua course in West Maui, the rest use private brackish wells or reclaimed water.
How much water does Maui use?
Who Uses Maui’s Water (based upon 2002-04 public records) Every day on Maui over 400 MGD of water, fresh and brackish, is used for domestic, industrial, commercial or agricultural purposes. Only around one-eighth, or 45 MGD of that amount is utilized for domestic and commercial use.
What is DBCP in water?
DBCP in Water- a Short History. The most common agricultural pollutant found in both private and public domestic wells on Maui is DBCP. Used in pineapple fields by ML&P, its use was banned in the US in the early 1980’s as a suspected carcinogen.
What is the importance of Maui?
The ancient Hawaiian auwai (water transport ditch) system is a marvel of engineering, still functioning today. It helped make possible a reliable food supply in valleys and coastal plains from Hana to Honokohau, which allowed many centers of Hawaiian culture, art and learning to flourish.
Does Maui have a ridge line?
There are physical boundaries associated with some of Maui’s aquifers (such as ridge lines, shorelines or gulches,) but many do not have any distinct geological or geographical boundaries and are separated from neighboring aquifers only by arbitrary lines on a map.
Is Maui's aquifer interconnected?
Realistically, a number of Maui’s individual aquifers are quite interconnected, but the state’s water study (HWRPP) assigned each of them a separate sustainable yield (SY) as if each had its own portion of useable water. This can be confusing and lead to inaccurate assumptions.
Is Maui a public water source?
Less than one-tenth of Maui’s water resources are actually under public control although billions of gallons of water originate on public lands. The vast majority of present use is for agricultural irrigation. Currently, and historically, Maui is the state’s biggest user of surface water.
How much nitrogen is in water treatment plants?
Our treatment plants use an aerobic biological process, nutrient removal and filtration. Because the water contains between 4 and 10 mg/l of Total Nitrogen (the regulatory limit is 10mg/l) - the effluent that our treatment facilities produce actually meets federal and state drinking water standards for Total Nitrogen.
How many Class V wells are there in Maui?
The EPA estimates that there are over 1.7 million injection wells throughout the United States. 3.
How is wastewater absorbed into wells?
Wastewater discharged into wells is absorbed by natural geologic formations, which complete the treatment by natural filtering through rock and sand layers. When properly sited, constructed and operated, injection wells are an economical, environmentally responsible and effective tool for safe wastewater management. 4.
Does Maui have an injection well?
Yes. There are numerous privately-owned and operated injection wells in our county. Many. privately-owned condominiums and businesses in areas that were built outside of existing County of Maui sewer service have their own injection well (s).
Is recycled water needed during rainy periods?
It is important to note that during rainy periods less recycled wastewater is needed and therefore less utilized – resulting in a larger percentage disposed of through injection wells. By making use of recycled water that comes from treated wastewater, potable water can be. conserved. 15.
Is Maui water treated differently than tap water?
The water sent to the injection wells at the County of Maui treatment plants looks no different than your tap water at home. In producing this water, the County of Maui goes beyond the minimum requirements set by state and federal regulators.
Can wastewater be reused?
More wastewater could be reused if there were additional pipeline infrastructure available. Because distributing recycled water requires a separate and dedicated pipeline, additional pipeline systems will need to be built and put in throughout the county in order to increase the amount of wastewater that is recycled.
What are the environmental issues in Maui?
The near shore coastal environment in certain areas of Maui County has been negatively impacted by land based pollution sources including sediment runoff and leaching of treated and untreated wastewater. Land based pollution is suspected of contributing to episodic macro algal blooms, coral reef decline and impaired ocean water quality. The disposal of treated and untreated wastewater through injection wells and cesspools has been a concern for years on Maui and recent scientific studies have indicated that wastewater is entering the near shore coastal environment through subsurface seeps and may be a significant source of environmental and health related issues. A study published in the Marine Pollution Bulletin by Miller-Pierce and Rhoads in 2016 reported that the water quality in the Kalama Park – Cove Park area of South Maui is high in pollution indicators such as turbidity, chlorophyll a, ammonium, nitrate-nitrite, total phosphorus and total nitrogen and that this area lies directly in the effluent plume from the County of Maui’s Kihei Wastewater Reclamation Facility’s (WWRF) wastewater injection wells.2 This study led to a workshop sponsored by the Maui Nui Marine Resource Council (MNMRC) in May, 2016 that covered the issue of wastewater’s role in coastal water quality challenges.
Where is Maui Meadows?
Maui Meadows has over 600 rural and agricultural zoned lots and is located mauka of the Piilani Highway above the north section of the Wailea region of South Maui (see Figure 6). This subdivision lies outside of the Kihei WWRF service area therefore each residence has its own IWS. Most residences utilize either a cesspool or a septic system. A cesspool is essentially a deep hole where untreated wastewater percolates down through the soil. Pathogens, nutrients and other pollutants can reach the groundwater and eventually the coastal waters through groundwater seeps. A septic system consists of a settling tank that allows solids to settle with the clarified effluent overflowing the tank and being disposed of through a drain field. A drain field consists of buried perforated pipes that allow the effluent to be dispersed over a wide area, typically in the yard of a residential lot. Solids must be pumped from septic tanks periodically to prevent drain field clogging. Figure 7 shows a cesspool. Figures 8 shows a septic tank and Figure 9 shows a complete septic system.
What is the most feasible and cost effective option to improve the quality of the effluents and reduce the use
Option 1 is the most feasible and cost effective option to improve the quality of the effluents and reduce the use of injection wells at the Maalaea condominiums. It also has the added benefit of contributing to sustainability by making use of the recycled water for landscape irrigation. Nutrients that do remain in the effluents can be used by the irrigated vegetation thus allowing the condominiums to reduce the use of chemical fertilizers on their properties.
How much does it cost to build a WWRF?
Constructing a new WWRF roughly costs about $35 to $40 per gallon of capacity. At $35 per gallon, and assuming that the facility would be designed for 0.315 MGD, the estimated total cost would be over $11 million. The cost of the wastewater collection system, land for the WWRF, a SAT system and a recycled water distribution system would need to be added to this cost of the WWRF. It is doubtful that property owners in Maui Meadows would elect to construct their own WWRF due to the extreme costs associated with this option.
What is aerobic sludge?
Aerobic: In the presence of oxygen . The activated sludge aerobic zones have a dissolved oxygen concentration of 2 -3 milligrams per liter. Aerobic conditions are necessary for secondary treatment (biological oxidation) of wastewater to occur.
What is enhanced nutrient removal?
Part of this program required WWRFs that discharge to the Bay to improve their nutrient removal capacity so that effluent total nitrogen does not exceed 3 mg/L and total phosphorous does not exceed 0.3 mg/L.4 ENR is accomplished by adding methanol or some other carbon source to either anoxic zones in activated sludge basins or to deep bed effluent filters. The additional carbon drives denitrification further so that lower total nitrogen and phosphorous levels can be achieved. The Kihei WWRF is not equipped with deep bed effluent filters. Thus, ENR could be accomplished by adding methanol to an anoxic zone in a Bardenpho Process configuration. This concept will need to be evaluated by a consulting engineering firm that specializes in wastewater treatment design to determine if it is feasible at the Kihei WWRF. Figure 4 shows the Bardenpho Process with supplemental carbon addition.
Where is the Kihei WWRF located?
The facility is located at 100 feet mean sea level just mauka of the Piilani Highway and in the vicinity of the Maui Nui Golf Club. The Kihei WWRF is designed to treat 8.0 million gallons per day (MGD) and currently receives a daily flow of approximately 4.0 MGD. On an annual average, about one-half or approximately
