HomeMy WebLinkAbout2021-09-22 EMC agenda item 7b - KWWTP water reuse recommendations
A Recommendation for a Major Policy Revision for the Operation of the
Kealakehe Wastewater Treatment Plant
August 30, 2021
RH Bennett Ph.D., Rick Gaffney-
Waiwai Ola Ohana
The Kealakehe Wastewater Treatment Plant (KWWTP) was built with public funds in the
provide sanitary sewer to hundreds of dwellings along Ali'i Drive and close cesspits that contaminated the
nearshore waters with fecal bacteria. The EPA grant also provided advanced water treatment and reuse
of the water for golf course and landscape irrigation. The reuse portion of the project never came to
fruition due in part to
management has been in a temporarydisposal pit that has received nutrient-rich wastewater for over 25
years. Published science affirms that the ocean is the recipient of this unlawful, wasteful, unsustainable
discharge.
As climate uncertainty descends upon the islands, and notably on West Hawaii, there is no water to
waste. Every gallon of water reclaimed and reused displaces and conserves groundwater resources.
Our groundwater is rainfall-dependent and located some 1500 feet below the wellheads. Pumping the
water for domestic use is fraught with challenges and extremely costly. Water reuse can defer significant
energy costs and conserve our water resource for the future continuing drought.
The KWWTP operates under the authorities of the Hawaii Department of Health HAR §11-62-25. The
plant functions as a wastewater disposal plant and is required to have a 100% backup disposal system.
That system does not currently exist and therefore was part of Brown and Caldwell's $160 million plant
upgrade design. The cost of the upgrade alone would preclude all investment in water reuse distribution
systems. The disposal plan is very unwise water resource policy.
Section §11-62-27 of the HAR specifies the conditions and operations of a Recycled Water System. The
KWWTP will soon treat the water to the R1 level. R1 water is approved for the irrigation of plants and
crops that will have human contact and usage. The only remaining requirement is suitable storage of the
R1 water. In an agronomic reuse scenario, water storage is an essential component of the system.
Storage accommodates periods of high and low crop water demands and is not optional for a successful
reuse program. Depending on how that storage is configured, the cost of additional storage ranges from
ten to twenty million dollars. A reuse plant can be constructed at 20% of the cost of the Disposal Plant
proposed by Brown and Caldwell in 2020.
Wastewater disposal has no option for cost recovery. Wastewater disposal is costly even without the
required discharge permits under the Clean Water Act. Since most of our coastal waters are "EPA
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Impaired" (Section 303 (d) of the Clean Water Act), it is improbable that a discharge permit would be
granted unless the county could attain a very high level of treatment to assure the discharge would not
further degrade the waters of the United States.
Water reuse for agronomic and agricultural purposes will create a sustainable agricultural economy. The
water will have a value that approaches that of freshwater. This value can offset the costs of the reuse
and distribution system, including pumping costs.
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33 U.S.C. § 303(d)(1)(A). Impaired bodies of water are water bodies in which existing pollution controls are
insufficient to attain or maintain water quality standards
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National Pollution Discharge Elimination System (NPDES) Permit, 33 U.S.C. § 1311(b)(1)(a)
Several steps are required to realize the reuse potential:
(1) The County of Hawaii needs to adopt a water conservation and water reuse policy that, among other
actions, designates and operates the KWWTP as a Recycling Plant under HAR §11-61-27. The KWWTP
Operations Manual is currently being revised. That revision should be for the exclusive recycling of
wastewater.
(2) The Department of Environmental Management should be funded adequately to resolve the problem
of saltwater infiltration into the sewer system. That will necessitate repairing leaking sewer lines and
adopting ordinances that require property owners to repair leaking sewer pipes that the county has
identified as problematic.Reducing the salt concentration in sewer water to make it equivalent to local
freshwater, is essential for agronomic reuse. Excessive chlorides from seawater are rather toxic for most
plants.
(3) The distribution and reuse of the water for agronomic purposes must be conducted consistent with
the best management practices for optimizing plant growth and efficient water use. The expertise for
properwater management exists at all the major golf courses. That same expertise will be critical for the
success of any county sponsored reuse projects.
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From a legal liability perspective, 100% reuse will allow for the closure of the unlawful wastewater sump
at Kealakehe. The ocean water quality will improve by closing the sump and thereby discontinuing its
drainage to the harbor and nearby shoreline. The probable liability from continued discharge will thereby
be resolved.
Perhaps most important is the long-term benefits to the people of Hawaii County. Water Reuse will
generate its own economy; it will create an income stream for the county and help offset the looming
infrastructure deficiencies. Water reuse will conserve water and power. The demonstration of sound
resource policy will bolster confidence in our ability to meet the challenges of climate change and make
our island home more sustainable.
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County of Maui v. Hawaii Wildlife Fund, No. 18-260, 590 U.S. ___ (2020)