*4.3. Water Environment Livability (WEL)*

Scores of RHI

WEL scores 70.4 points nationwide, which is generally at a medium level. The overall water environment livability nationwide is: the water quality of rivers generally reaches a good level and QDS is at a near-good level, but groundwater resources are poorly conserved, lakes and reservoirs are seriously eutrophic and there is a gap between the environment of urban and rural waters closely related to people's daily life and their water entertainment demand. The vision of "a livable environment with clear waters and green banks" is still far away.

WEL evaluation results for the first-grade water resource zones are shown in Figure 5. Specifically, southeastern rivers score 90.7 points, performing best and reaching a good level; both the Yangtze River and southwestern rivers score 80+ points, staying at a medium-high level; the Pearl River and northwestern rivers score 70–80 points, at a medium level; the Taihu Lake, the Yellow River and the Huaihe River score 60–70 points, at a medium-low level; while the Songhua River, the Haihe River, and the Liaohe River score less than 60 points, at a poor level.

WRR Score Average Score First-grade water resources zones

Scores of RHI

**Figure 3.** FCC evaluation results for China's first-grade water resource zones.

First-grade water resources zones FCC Score Average Score

the Taihu Lake are higher than 80 points, reaching a medium-high level.

WRR scores 77.1 points nationwide, which is generally at a medium level. The overall water resource reliability nationwide is: AWP stands at a medium-high level against the international warning line for water shortage, WSR is at a good level, and WUR is well below 40%, but water resources are unevenly distributed across regions, which is incompatible with population distribution and allocation of productive forces; the level of water conservancy is yet to be further improved, and there is a clear gap in GDP Output per cubic meter of Water use (GOW) compared with high-income countries; and CSD is generally at a medium-low level. Continuing to play the basic role of happy rivers and lakes to achieve the vision of "an affluent life with reliable water supply" is still on the way.

WRR evaluation results for the first-grade water resource zones are shown in Figure 4. In general, scores in the north are lower than in the south. Specifically, scores for the Yellow River, the Haihe River, the Huaihe River, northwestern rivers, and the Liaohe River are all below 70 points, at a medium-low level. Scores for southeastern rivers and

*4.2. Water Resources Reliability (WRR)*

**Figure 4.** WRR evaluation results for China's first-grade water resource zone **Figure 4.** WRR evaluation results for China's first-grade water resource zone. dium-low level; while the Songhua River, the Haihe River, and the Liaohe River score less than 60 points, at a poor level.

**Figure 5.** WEL evaluation results for China's first-grade water resource zones. **Figure 5.** WEL evaluation results for China's first-grade water resource zones.

#### *4.4. Aquatic Ecosystem Health (AEH) 4.4. Aquatic Ecosystem Health (AEH)*

lowest, at a poor level.

AEH scores 74.1 points nationwide, which is generally at a medium level. The overall aquatic ecosystem health nationwide is: owing to fruitful water and soil conservation efforts, SWC reaches a good level, and under the support of steady guarantee for ecological flows and management through the river/lake chief system, REF generally improved to a medium level; however, both NHR and IBI are still at a medium-low level. The quality and stability of river and lake ecosystems should be systematically improved before the vision of "a symbiotic harmony with fish swimming in shallows" can be achieved. AEH scores 74.1 points nationwide, which is generally at a medium level. The overall aquatic ecosystem health nationwide is: owing to fruitful water and soil conservation efforts, SWC reaches a good level, and under the support of steady guarantee for ecological flows and management through the river/lake chief system, REF generally improved to a medium level; however, both NHR and IBI are still at a medium-low level. The quality and stability of river and lake ecosystems should be systematically improved before the vision of "a symbiotic harmony with fish swimming in shallows" can be achieved.

AEH evaluation results for the first-grade water resource zones are shown in Figure 6. Southwestern rivers and the Songhua River score 85+ points, the highest among the first-class water resource zones, reaching a good level; scores for the Taihu Lake, the Pearl River, the Yangtze River, southeastern rivers, the Huaihe River, and northwestern rivers fall between 70 and 80 points, all at a medium level; the Liaohe River and the Haihe River AEH evaluation results for the first-grade water resource zones are shown in Figure 6. Southwestern rivers and the Songhua River score 85+ points, the highest among the firstclass water resource zones, reaching a good level; scores for the Taihu Lake, the Pearl River, the Yangtze River, southeastern rivers, the Huaihe River, and northwestern rivers fall between 70 and 80 points, all at a medium level; the Liaohe River and the Haihe River

score 60–70 points, both at a medium-low level; the Yellow River scores 56.8 points, the

score 60–70 points, both at a medium-low level; the Yellow River scores 56.8 points, the lowest, at a poor level. *Water* **2022**, *14*, x FOR PEER REVIEW 13 of 20

**Figure 6.** AEH evaluation results for China's first-grade water resource zones. **Figure 6.** AEH evaluation results for China's first-grade water resource zones.

#### *4.5. Water Culture Prosperity (WCP) 4.5. Water Culture Prosperity (WCP)*

WCP scores 77.0 points nationwide, which is generally at a medium level. The overall water culture prosperity nationwide is: China boasts a profound historical background of water culture, which represents a precious treasure for achieving the vision of "a spiritual homeland with river civilizations"; however, both CPI and MCI are low, and PAE, which indicates the respect for and protection of rivers, is generally low and still at a medium level relative to people's increasing demand for cultural life, which is yet to improve. WCP scores 77.0 points nationwide, which is generally at a medium level. The overall water culture prosperity nationwide is: China boasts a profound historical background of water culture, which represents a precious treasure for achieving the vision of "a spiritual homeland with river civilizations"; however, both CPI and MCI are low, and PAE, which indicates the respect for and protection of rivers, is generally low and still at a medium level relative to people's increasing demand for cultural life, which is yet to improve.

WCP evaluation results are shown in Figure 7. Scores for the Yangtze River, the Yellow River, the Huaihe River, southeastern rivers, the Pearl River, and the Taihu Lake all exceed 80 points, reaching a medium-high level; the Haihe River, southwestern rivers, and northwestern rivers score 70–80 points on WCP at a medium level; scores for the Songhua River and the Liaohe River are relatively low, which are 68.8 and 67.5 points, respectively, at a medium-low level. WCP evaluation results are shown in Figure 7. Scores for the Yangtze River, the Yellow River, the Huaihe River, southeastern rivers, the Pearl River, and the Taihu Lake all exceed 80 points, reaching a medium-high level; the Haihe River, southwestern rivers, and northwestern rivers score 70–80 points on WCP at a medium level; scores for the Songhua River and the Liaohe River are relatively low, which are 68.8 and 67.5 points, respectively, at a medium-low level.

#### *4.6. Overall Evaluation*

Scores of RHI

In 2019, the FCC score was the highest nationwide, reaching a near-good level, while scores of WRR, WEL, AEH, and WCP fell between 70 and 80 points, all at a medium level (Figure 8).

WCP Score Average Score First-grade water resources zones In 2019, China's RHI scored 77.1 points at a medium level. On the whole, among the secondary indicators, the mortality rate, water supply rate, and soil and water conservation rate of flood disaster were relatively the highest, reaching a good grade. The economic loss rate of flood disasters, the standard rate of flood control projects, the per capita water resources availability, and the river and lake water quality index scored the second highest, which belonged to the medium-high grade. The degree of protection of groundwater resources and the degree of water entertainment score was low, and the evaluation grade was poor. The score for water resources supporting development ability, natural habitat retention rate, and aquatic biological integrity was the second lowest, which was mediumlow level. The conditions of rivers and lakes in China calculated by RHI are consistent with the actual situation. The overall RHI evaluation results are shown in Figure 9. Specifically, RHI scores for southeastern rivers and the Taihu Lake were the highest, at a medium-high level, and RHI scores for the Yangtze River, southwestern rivers, and the Pearl River were

**Figure 7.** WCP evaluation results for China's first-grade water resource zones.

Scores of RHI

79.9, 79.4, and 79.3 points, respectively, all at a medium level. RHI scores for these southern first-grade water resource zones were higher than the national average. In the north, the Songhua River had the highest RHI score, which was 75.8 points (close to the national average), while the Yellow River, the Huaihe River, and northwestern rivers scored a little more than 70 points, indicating a medium level of river happiness. Scores for the Liaohe River and the Haihe River lay between 60 and 70 points, indicating a medium-low level of river happiness. indicates the respect for and protection of rivers, is generally low and still at a medium level relative to people's increasing demand for cultural life, which is yet to improve. WCP evaluation results are shown in Figure 7. Scores for the Yangtze River, the Yellow River, the Huaihe River, southeastern rivers, the Pearl River, and the Taihu Lake all exceed 80 points, reaching a medium-high level; the Haihe River, southwestern rivers, and northwestern rivers score 70–80 points on WCP at a medium level; scores for the Songhua River and the Liaohe River are relatively low, which are 68.8 and 67.5 points, respectively, at a medium-low level.

WCP scores 77.0 points nationwide, which is generally at a medium level. The overall water culture prosperity nationwide is: China boasts a profound historical background of water culture, which represents a precious treasure for achieving the vision of "a spiritual homeland with river civilizations"; however, both CPI and MCI are low, and PAE, which

**Figure 6.** AEH evaluation results for China's first-grade water resource zones.

AEH Score Average Score First-grade water resources zones

*4.5. Water Culture Prosperity (WCP)*

*Water* **2022**, *14*, x FOR PEER REVIEW 13 of 20

**Figure 7.** WCP evaluation results for China's first-grade water resource zones. **Figure 7.** WCP evaluation results for China's first-grade water resource zones. scores of WRR, WEL, AEH, and WCP fell between 70 and 80 points, all at a medium level (Figure 8).

**Figure 8.** Evaluation results of the first-level indicators of the RHI in China. **Figure 8.** Evaluation results of the first-level indicators of the RHI in China.

In 2019, China's RHI scored 77.1 points at a medium level. On the whole, among the secondary indicators, the mortality rate, water supply rate, and soil and water conservation rate of flood disaster were relatively the highest, reaching a good grade. The economic loss rate of flood disasters, the standard rate of flood control projects, the per capita water resources availability, and the river and lake water quality index scored the second highest, which belonged to the medium-high grade. The degree of protection of groundwater resources and the degree of water entertainment score was low, and the evaluation grade was poor. The score for water resources supporting development ability, natural habitat retention rate, and aquatic biological integrity was the second lowest, which was mediumlow level. The conditions of rivers and lakes in China calculated by RHI are consistent with the actual situation. The overall RHI evaluation results are shown in Figure 9. Spe-

dium-high level, and RHI scores for the Yangtze River, southwestern rivers, and the Pearl River were 79.9, 79.4, and 79.3 points, respectively, all at a medium level. RHI scores for these southern first-grade water resource zones were higher than the national average. In the north, the Songhua River had the highest RHI score, which was 75.8 points (close to the national average), while the Yellow River, the Huaihe River, and northwestern rivers scored a little more than 70 points, indicating a medium level of river happiness. Scores for the Liaohe River and the Haihe River lay between 60 and 70 points, indicating a me-

dium-low level of river happiness.

FDS

RWR

RWA

CSD

LSI

**Figure 9.** RHI evaluation results for China's first-grade water resource zones. **Figure 9.** RHI evaluation results for China's first-grade water resource zones.

#### *4.7. Evaluation of a Typical River Basin 4.7. Evaluation of a Typical River Basin*

The Yellow River, having nurtured and bred the Chinese civilization, is also an important economic zone in China, with the Huang-Huai-Hai Plain, the Fenwei Plain, and the Hetao Irrigation Area being major agricultural production areas, which contribute to around one third of the country's food and meat production. The Yellow River Basin, also known as the "Energy Basin", boasts abundant coal, oil, gas, and nonferrous metal resources, with coal reserves there accounting for more than half of the national total. It is an important base for energy, chemicals, raw materials, and basic industries in China. The Yellow River, having nurtured and bred the Chinese civilization, is also an important economic zone in China, with the Huang-Huai-Hai Plain, the Fenwei Plain, and the Hetao Irrigation Area being major agricultural production areas, which contribute to around one third of the country's food and meat production. The Yellow River Basin, also known as the "Energy Basin", boasts abundant coal, oil, gas, and nonferrous metal resources, with coal reserves there accounting for more than half of the national total. It is an important base for energy, chemicals, raw materials, and basic industries in China.

The RHI scores 71.0 points in the Yellow River Basin, staying at a medium level and putting the river basin in eighth place among the 10 first-grade water resource zones nationwide. The evaluation results of the first-level indicators of the RHI are listed in Table 8. As shown in the table, the FCC score is the highest, reaching a good level; WCP is at a medium-high level; the AEH score is the lowest, at a poor level; and other indicators are at a medium-low level. The RHI scores 71.0 points in the Yellow River Basin, staying at a medium level and putting the river basin in eighth place among the 10 first-grade water resource zones nationwide. The evaluation results of the first-level indicators of the RHI are listed in Table 8. As shown in the table, the FCC score is the highest, reaching a good level; WCP is at a medium-high level; the AEH score is the lowest, at a poor level; and other indicators are at a medium-low level.

**Table 8.** RHI evaluation results for the Yellow River Basin. **Criterion Layer Indicator Layer Benchmark Value Status Quo Value Score Weight Subtotal** FMR 0% 0.40% 91.9 0.30 ELR 0% 0.22% 85.3 0.30 RAL 100% 87.5% 87.5 0.12 FCC. FCC scores 88.9 points in the Yellow River Basin, generally at a good level. Rate of Accepted Dikes (RAD) is 87.7%, the Rate of Accepted Reservoirs for medium-sized and large reservoirs (RAR), and the Rate of Accepted flood detention Basins (RAB) are 100% and RAR (for small reservoirs) is 98%, so RWA scores 94.7 points, reaching a near-excellent level. FMR (0.4 per million people) scores 91.9 points and ELR is 0.22%, which scores 85.3 points, both at a good level. DRC scores 73.7 points, at a medium level, indicating relatively weak resilience.

> 88.9 PAR 100% Medium-sized and large reservoirs: 100%, small reservoirs: 98% 99.2 0.12 PAD 100 100.00 100.0 0.06 DRC 100 73.7 73.7 0.10 AWP 10,000 m<sup>3</sup> /per 620.21m<sup>3</sup> /per 44.8 0.20 WRR. WRR scores 64.6 points in the Yellow River Basin, generally at a medium-low level. Water Supply Coverage (WSC) is 91.3% and the Rate of actual Irrigated Areas (RIA) is 79.9%, so WSR scores 86.3 points, reaching a good level; LSI scores 77.0 points, at a medium level; AWP is 620.2 m<sup>3</sup> , scoring 44.8 points, and as Water resources Utilization Rate (WUR) exceeds 70% and GDP Output per cubic meter of Water use (GOW) is RMB 180.5/m<sup>3</sup> , CSD scores 42.0, both at a poor level that is still a long way from the medium level.

64.6 WSR WSC 100% 91.31% 91.3 0.17 PIA 100% 79.86% 79.9 0.13 WER 40% 70.76% 50.6 0.12 GOW 509 m<sup>3</sup> 180.51 m<sup>3</sup> 34.0 0.13 GDP 132,400 (RMB) 59,502.17 (RMB) 43.1 0.08 ENC 25% 26.58% 94.1 0.09 WEL. WEL scores 66.2 points in the Yellow River Basin, generally at a mediumlow level. To be specific, the groundwater exploitation coefficient is 1.04 and GPI scores 26.0 points, staying at a very poor level; WEI scores 69.8 points, standing at a medium-low level; QDS scores 74.5 points, at a medium level; the length of rivers with Class I~III water quality accounts for 80.3% and that of rivers with water quality inferior to Class V accounts for 9.2%, and the Rate of Eutrophic Lakes and reservoirs (REL) is 25%, so WQI scores 82.2 points, at a medium-high level.

ALE 81 74.16 91.6 0.08


**Table 8.** RHI evaluation results for the Yellow River Basin.

AEH. AEH scores 56.8 points in the Yellow River Basin, generally at a poor level. SWC scores 85.7 points, at a medium-high level, the highest among the second-level indicators, followed by NHR, which scores 77.2 points, at a medium level; IBI scores 42.9 points, at a poor level; and REF scores 25.0 points, at a very poor level.

WCP. WCP scores 80.6 points in the Yellow River Basin, generally at a medium-high level. CPI scores 86.8 points, reaching a good level; MCI scores 81.0 points, at a mediumhigh level; and PAE scores 76.3 points and WLI scores 78.4 points, both at a medium level.

The RHI evaluation results for the Yellow River Basin suggest that the main problems are in the following areas: first, inadequate post-disaster recovery capability is the main risk affecting water security in the Yangtze River Basin; second, an inherent shortage of water resources and a high rate of water resource exploitation and utilization remain the biggest restrictions on high-quality economic and social development; third, serious groundwater overdraft in some areas and heavy pollution of tributaries are major problems to be solved as early as possible in order to create a livable water environment in the river basin; fourth, the low rate of rivers with accepted ecological flows is a weak link to be addressed in order to maintain healthy water ecology; and fifth, the brand effect of water culture is yet to be enhanced and the water landscape impact is yet to be improved.

#### **5. Discussion**

#### *5.1. Uncertainty of the Evaluation Method*

Happiness is a subjective feeling for people, and rivers that make people feel happy should have common objective characteristics in terms of water security, water resources, water environment, water ecology, and water culture. Based on the five dimensions, the RHI is composed of altogether 30 indicators, including five first-level indicators, namely FCC, WRR, WEL, AEH, and WCP, each of which consist of four second-level indicators and corresponding third-level indicators. In the process of evaluation, the determination of weight coefficients is crucial. At present, research on evaluation indicators more often employs entropy weight, standard deviation, and Criteria Importance Through Intercriteria Correlation (CRITIC) methods, which can calculate indicator weights through mathematical methods based on original data, but render the scope of application limited, as they fully reflect the characteristics of selected data. Since the degree of flood control construction, water environment protection, utilization, and demand varies greatly from river to river due to the complexity of each river, selecting a universal indicator system that takes into account the characteristics of different rivers is vital to the evaluation of rivers.

#### *5.2. Applicability of the Evaluation Method*

Current evaluation of rivers mainly deals with the hydrological condition of natural attributes, ecosystems, and social functions of rivers, with focus on the health of rivers and different indicator systems established for different rivers. For instance, the Upper Mississippi River Restoration Program (UMRRP) assessed the ecosystem health of the Upper Mississippi River using seven categories of indicators, such as hydrology, sedimentation, water quality, land cover, aquatic vegetation, invertebrate and fish, and 25 specific monitoring indicators. The status and trend reports published indicate that most indicators remain relatively stable, with ecosystems being healthy in the north and relatively unhealthy in the south [28,29]. With a growing demand for quality of life, healthy evaluation of a river's happiness should adopt a people-centered approach that not only assesses the general social and economic functions of the river by systematically measuring its water security, water supply, and water environment services, but also scientifically examines its aquatic ecosystem quality and water culture prosperity in the light of the natural endowments and cultural background of the river basin [30]. Therefore, in the case of the Mississippi River, the RHI scores 80.1 points, at a medium-high level. To break it down, FCC scores 90+ points, which is at a good level; WRR and WEL score 80+ points, both at a medium-high level; and AEH and WCP score less than 80 points, both at a medium level. The evaluation results show the following characteristics of the Mississippi: first, the river basin is generally well managed and reaches a medium-high level in terms of water security, water resources, and water environment, indicating that the long-term systematic governance of the river basin produced desirable results and a high level of public awareness and engagement in water governance; second, low scores on the eco-hydrological process variation index and the longitudinal connectivity index imply the great impact of human activity on natural habitats and a high rate of water resource development; and third, historical and cultural inheritance and protection is inadequate in the river basin. From the perspective of the evaluation results, the RHI performs better in comprehensively describing the overall situation of a large river.

#### *5.3. Policy Recommendations*

River health, as a comprehensive concept, is increasingly embodied in domestic and foreign water resource management systems, but there are no specific rules for the imple-

mentation of river evaluation indicator systems, and the indicator systems selected for a single river may vary. In order to scientifically assess the status of rivers and lakes in different regions, an international guideline for river and lake evaluation should be introduced, which can take into account the differences and commonalities of river ecosystems and provide a unified, standardized technical system for evaluation. This requires a unified indicator system, under which proper adjustments can be made to indicators according to the situation of a specific river basin, but such adjustments should meet scientific cognition, assessment standards, and other requirements. Major rivers and lakes should be assessed on a regular basis. In response to underperforming indicators, such as RWA, GPI, and REF, the problem of unbalanced spatial distribution of water resources should be addressed as early as possible. For underperforming indicators, such as AWP and WUR, the principle of giving priority to saving water must be put into practice. For underperforming indicators such as WEI, IBI, and CPI, scientific sector-specific decisions should be made.

#### **6. Conclusions**

As social and economic development needs and anthropogenic threats grow, countries around the world are suffering from numerous river and lake problems, such as altered hydrological processes, damaged physical structures, polluted water, and declining aquatic biodiversity, and the evaluation of rivers and lakes is changing from purely water quality evaluation to a more comprehensive one. This paper gives a new definition of a happy river, which enriches the new connotation of water management. A happy river refers to a river that can maintain its own health, support high-quality economic and social development in the river basin, as well as reflect human–water harmony, thus give people a high sense of security, gain, and satisfaction. The RHI method is based on Maslow's hierarchy of needs theory and draws lessons from the World Happiness Report and SDG Report. Compared with the previous studies, the study insisted on a people-centered approach, and takes the river culture into consideration. This paper develops evaluation indicators, such as FCC, WRR, WEL, AEH, and WCP in terms of water resources, security, ecology, environment, and culture, and assesses the overall river happiness of major rivers and lakes nationwide by examining the situation of China's 10 first-grade water resource zones and the Taihu Lake Basin in 2019.

The analysis of the evaluation indicators suggests that China's RHI scores 77.1 points, which is at a medium level, with FCC at a near-good level and WRR, WEL, AEH, and WCP all at a medium level. Meanwhile, the RHI in first-grade water resource zones in southern China stands above the national average, in contrast to the situation in the north, mainly because WRR and WEL are lower in the north than in the south.

The analysis of the river basins evaluated supports that WEL for the Songhua River, the Liaohe River, and the Haihe River in the north is at a poor level, restricting the quality and stability of aquatic ecosystems; AEH for the Yangtze River, the Taihu Lake, and southeastern rivers in the south is at a below-average level, indicating the poor condition of important aquatic organisms, which is a major problem that requires attention in order to maintain healthy aquatic ecosystems in these regions. Problems in the Yellow River Basin, which involves 340 counties (county-level cities, districts, or banners) in 66 prefectures (prefecturelevel cities, autonomous prefectures, or leagues) in nine provinces and autonomous regions, are more complex, with FCC reaching a good level, WCP at an above-average level, AEH at a poor level, and WRR and WEL at a below-average level. Based on the evaluation results, we therefore propose targeted basin governance measures: more attention should be paid to the intensive and economical use of water resources in northern China, and ecological flows of rivers must be effectively ensured in southern.

On the whole, happy rivers should be built in a way that seeks to maintain the health of rivers while pursuing greater benefits for the people by following the basic principle of human–water harmony on the premise of maintaining river health. With regard to the perspective of the future work, except the expert comprehensive evaluation method applied in the current study, the index weights can also be determined by the Analytic Hierarchy Process (AHP), considering the characteristics of the river basin, social and economic conditions, or people's opinions. Secondly, at present the model may not include all aspects of a river, such as its hydrodynamics, transport, and species migration, so more relevant aspects can be supplemented and studied in subsequent work. Furthermore, building happy rivers and lakes is not only applicable to those in China, but also in the rest of the world. To this end, a guideline must be developed as soon as possible to provide technical support for the building of happy rivers and lakes. We will continue to select more representative world rivers to verify the accuracy and adaptability of the RHI evaluation method.

**Author Contributions:** Conceptualization, C.L.; methodology, C.L. and S.J.; formal analysis, C.L. and Q.J.; writing—original draft preparation, Q.J.; writing—review and editing, C.L. and S.J.; visualization, Q.J.; supervision, C.L.; All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the National High Technology Research and Development Program of China (No.2021YFC3200205); and the Cooperation Project of Shandong Water Transfer Operation and Maintenance Center (No.37000000025002920210100001).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data that support the finding of this study are available from the corresponding author upon reasonable request.

**Conflicts of Interest:** The happy river research group of the China Institute of Water Resources and Hydropower Research is involved in relevant work.

#### **References**


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