Hydrograph Procedure Suspension
May 14, 2024 Update
As of April 1st, 2024, the Hydrograph Procedure may not be used as an alternate method to the standard soil test. This means no new evaluations using the Hydrograph Procedure.
Sites previously utilizing the Hydrograph Procedure and already approved by the county, will continue to be valid for the purposes of designing POWTS and obtaining sanitary permits. The recent suspension of the Hydrograph Procedure in Adams, Juneau, Portage, Waushara, and Wood Counties has generated a certain level of concern and confusion. The DSPS POWTS Program would like to use this opportunity to list and detail the options that may be considered for POWTS system elevations on new and replacement sites in affected counties. Here are options in lieu of the former hydrograph procedure SPS 385.60(4):
SPS 385.60 (2) Interpretive Determination Reports. These comprehensive soil/data reports are site specific. Besides the requirements listed, the Department uses any and all data provided to make its determination on the site’s limiting features.
SPS 385.60(3) Soil Saturation Determinations. This procedure typically takes more time. It offers an effective alternative to the Hydrograph procedure.
SPS 385.60 (5) Artificially controlled Navigable Waters. Like the other options, sandy soil is required for consideration. Note: Distance from the controlled flow navigable water is critical to consider, and the control must be a recognized management entity.
Standard Soil Evaluation Report SPS 385.20 – SPS 385.40. Prepare a Soil Report using the code. This will likely result in an At-Grade or Mound type system in areas they would have otherwise gained that separation using the previous “Suspended” Hydrograph Procedure. Note: Soil Color Pattern Exemptions as described in SPS 385.30 (3) (1) will not be accepted unless proper data and evidence is provided. This could lead to further failing systems if there is no evidence to suggest or prove soil color pattern exemptions. Utilizing an exemption as a “work around” is not an acceptable practice.
Moving forward, Department staff will keep working with the State Geologist and other experts to better understand ground water flooding. Cooperation and collaboration with county agents is critical. Their soil evaluation data, permitting information, and input aids in future decisions. We want to develop standards to re-instate the Hydrograph Procedure that address well construction of proposed Hydrograph Wells, consistent hydrograph methods and data collection, extrapolation distance from those wells, department review of county data to utilize a well, and maps detailing where the process should or should not be used in a particular county.
The DSPS POWTS Program understands this suspension will not always lead to an equivalent plan as compared to the “former” Hydrograph Procedure. Our mission includes protecting the public, and continuation of the Hydrograph Procedure as previously prescribed could lead to health issues on certain sites. Building back a Hydrograph Procedure that accurately predicts groundwater levels will greatly reduce the likelihood of serious health risks.
Also see the original April 1, 2024, notice below.
April 1, 2024 Notice
The groundwater levels in Wisconsin Central Sands Region (parts of Adams, Juneau, Portage, Waushara, and Wood counties) have become erratic due to recent, significant recharge events. Department of Safety and Professional Services (DSPS) Private Onsite Wastewater Treatment System (POWTS) Program staff observed the erratic groundwater levels and consulted with the Wisconsin State Geologist’s Office at the Wisconsin Geological and Natural History Survey (WGNHS) and the POWTS Technical Advisory Committee. All parties recommend that the hydrograph procedure as described in Wis. Admin. Code § SPS 385.60(4) be suspended at this time.
Pursuant to Wis. Admin. Code § SPS 385.60(4)(f), “the governmental unit or the department may reject or suspend use of the hydrograph procedure when erratic groundwater tables are present due to recent, significant recharge events.” These conditions have been observed by DSPS staff and confirmed by WGNHS staff. Accordingly, DSPS suspends the hydrographic procedure for soil saturation determinations effective immediately. Any plans received after the effective date of this Notice will require one of the alternative methods of soil evaluation to be utilized.
Under Wis. Admin. Code ch. SPS 385, the hydrograph procedure is one of several methods for certified soil testers to utilize when performing a site and soil evaluation. During this period, where the use of the hydrograph procedure is suspended, certified soil testers may continue to utilize all other methods of performing site and soil evaluations such as a soil morphological evaluation under SPS 385.20, interpretive determinations under SPS 385.60(2), and soil saturation determinations under SPS 385.60(3).
DSPS will continue to consult with the WGNHS and the POWTS Technical Advisory Committee concerning the matter. The suspension of the hydrographic procedure will remain in effect until such a time that groundwater levels normalize, and suitable controls are in place to safely allow for the use of the method.
If you have questions regarding this notice, please contact DSPSSBPowtsTech@wisconsin.gov